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Bullet-Proofing Gottlieb System 80Pinball from 1980 to 1989

by cfh@provide.net.Copyright 1998-2007, all rights reserved.

Scope: Includes Gottlieb pinball System 80, 80a, 80b games from Spiderman (1/80) to Bone Busters (8/89). The most popular System 80 games that this information particularly applies to are Black Hole (10/81) and Haunted House (2/82).

Internet Availability of this Document.Updates of this document are available for no cost at http://marvin3m.com/fix.htm if you have Internet access. This document is four parts (part one, part two, part three, part four).

IMPORTANT: Before Starting!IF YOU HAVE NO EXPERIENCE IN CIRCUIT BOARD REPAIR, YOU SHOULD NOT TRY TO FIX YOUR OWN PINBALL GAME! Before you start any pinball circuit board repair, review the document at http://marvin3m.com/begin, which goes over the basics of circuit board repair. Since these pinball repair documents have been available, repair facilities are reporting a dramatic increase in the number of ruined ("hacked") circuit boards sent in for repair. Most repair facilities will NOT repair your circuit board after it has been unsuccessfully repaired ("hacked") by you. If you aren't up to repairing your circuit boards yourself, refer to the parts & repair web page for help.

Bibliography.In the creation of this document, some information came from the following sources:

Gottlieb Service Bullentins, Gottlieb, 1980 to 1990. Gottlieb Star Series 80 Service Manual, 1982. Available from Pinball Resource. John Robertson web articles. Black Hole/Haunted House Gottlieb System 80 Club of America, J. Cook, 1994.

Thanks goes to the following people that helped with this document. This includes Rob Hayes, John Robertson, and Pascal Janin.

Table of Contents

0. Getting Started: a. Introduction, Schematics, Books b. System 80 Games List, Numbers c. System 80 Parts to have on-hand d. Check the Coil Resistance.

1. Mandatory Fixes:

e. Circuit Board Defects f. Power Supply Fix g. Battery Replacement/Corrosion (CPU board Reset/Clock Circuits) h. Ground Problem Fix (CPU and Driver board) i. Connector Problems j. Pop Bumper Driver Board Fixes and Mods k. Pull Up Resistor Addition l. Check the Coil Resistance.

2. Suggested Fixes:

m. Kicker Solenoid Fuses/Switch Arc Fix n. Haunted House Up Kicker Fix o. Protecting Display "Nipples" p. Permanently "fixing" the Slam Switch

3. Other Information and Fixes:

q. Testing Transistors (and Driver Board Info) r. Transistor Info/Substitutes s. Fuse List for HH/BH t. CPU Board Revision Mods u. Score Displays v. Auxiliary Lamp Driver Board w. Repair Comments (General, Sound, Solenoids) x. Black Hole Motor Fix y. Haunted House Trap Door z. System 80 Reset Board aa. Setting Free Play bb. Black Hole Solenoid Test Correction cc. Switch Matrix for Haunted House dd. Transistor/Coil List for HH/BH ee. Connector/Transistor/Coil List for HH/BH ff. CPU Connector Pinouts gg. Dip Switch Settings hh. Bookkeeping and Self Test ii. Replacing CPU board U2/U3 ROMs to EPROMs. jj. Updating old CPU boards. kk. Gottlieb Rubber Part Number/Size Chart.

4. Systematic Gottlieb System 80 Circuit Board Repair

Fixing the System80 CPU board. Fixing the System80 Sound and Speech board.

0a. Getting Started: Introduction, Schematics, Books

Introduction.Gottlieb's System 80 machines had a variety of manufacturer and design problems, which this page will address. Doing the mandatory modifications outlined below will make a Gottlieb System 80 game extremely reliable. Certainly as reliable as any other game made during its time.

During the early 1980's, many Gottlieb System 80 games were very advanced for their time. For example, Haunted House and Black Hole have some design features that haven't been seen since (large lower playfields, and in Haunted House's case, a three level playfield). These game were a few years ahead of their time. But due to various problems, they received a bad reputation as being undependable. This information corrects these problems.

To keep a System 80 game running, do all the mandatory *and* recommended fixes. But at the minimum, do the mandatory fixes.

Tools and Experience Needed.Please see http://marvin3m.com/begin for details on the basic electronics skills and tools needed.

Schematics.All Gottlieb System80 schematics and many parts are available from one of the sources on the suggested parts & repair sources web page. Schematics really are required to work on these games. If in a hurry, there are some schematics available for download. These were all scanned from a 1980 Black Hole manual, and should generally be applicable for most System80 games up to Haunted House. After Haunted House, some of the following schematics (like the driver board) should still apply, with only minor changes.

Bottom board and cabinet wiring (90K) Power supply board layout (37K) Power supply (40K) Solenoid driver board layout (65K) Solenoid driver board (122K) CPU board layout (84K) CPU board (210K) Pop bumper driver board (modified) (17K) Black Hole Playfield solenoids and illumination wiring (140K, applies only to

Black Hole)

More System80 Repair Info.My site deals mostly with modifications needed to make a system80 game reliable. There is some additional CPU repair information available at the Systematic Gottlieb System 80 Circuit Board Repair web page. For addition repair info, John Kirby has also developed a nice site on system80 repair:

Main repair tips page CPU Startup problems CPU Board problems Driver Board (Coil) Problems Switch problems Power Supply problems Sound problems

Gottlieb Technical Seminar Workbook.The 1983 System 80/80a technical seminar workbook is also available for download. This is a great overview of the system 80 pinball system, with indepth

and easy to understand text. To download this 3.4 meg file, click sy80tech.pdf. Adobe Acrobat is required to view this document.

Gottlieb Service Bullentins.There are some Gottlieb service bullentins posted at http://www.geocities.com/system80pins/sb.html.

Star Tech Journal Modifications.Important Note: It is highly recommended to not do any of the "Star Tech Journal" System 80 modifications outlined in their books and CD rom. Follow the instructions here instead.

Other System80 Books, Resources and Parts.Highly recommended is the J. Cook book, "Black Hole/Haunted House Gottlieb System 80 Club of America". The book is great at identifying problems and provides good solutions (unfortunately, it is poorly organized, and the information is difficult to extract). This web page was inspired by this book, so it is good to have. It is available from www.pbliz.com/id44.htm. Also there is a Gottlieb System 80 Service manual available from Pinball Resource for $12. Pinball Resource is also the only authorized Gottlieb pinball parts dealer in America. John Robertson has some information on Gottlieb problems at www.flippers.com/got-tips.html. Also Pascal Janin sells some NEW system 80 boards (but not the CPU or driver board). A list of his boards can be seen at www.geocities.com/system80pins/pascal.html There is other general System80 information at the "Stork's Nest" pinball web site at www.geocities.com/system80pins/.

0b. Getting Started: System 80 Games List, Numbers

System 80Six digit numeric displays, board marked DET PB03-D102-001 (early version), or DET PB03-D107-001 (James Bond and newer), U2/U3 not socketed.

Spiderman #653, 1/80 Panthera #652, 5/80 Circus #654, 6/80 Counterforce #656, 8/80 Star Race #657, 10/80 James Bond #658, 10/80 Time Line #659, 11/80 Force II #661, 1/81 Pink Panther #664, 3/81 Mars God of War #666, 4/81 Volcano #667, 7/81 Black Hole #668 (& Eclipse #671 &

671K for kit version), 10/81 Haunted House #669, 2/82

System 80aSeven digit numeric displays. U2 and U3 now use sockets. No DET number.

Devil's Dare #670, 8/82 Caveman #810PV, 9/82 Rocky #672, 9/82 Spirit #673, 11/82 Punk #674, 12/82 Striker #675, 1/83 Krull, #676, 2/83 Q*bert's Quest #677, 3/83 Super Orbit #680, 5/83 Royal Flush Dlx #681, 6/83 Goin Nuts, #682, 1982 Amazon Hunt #684, 9/83 Rack 'Em Up #685, 11/83 Ready Aim Fire #686, 11/83 Jacks to Open #687, 5/84 Alien Star #689, 8/84 The Games #691, 8/84 Touchdown #688, 2/85 El Dorado #692, 3/85

Ice Fever #695, 5/85

System 80bAlpha-Numeric displays, U2/U3 chips are replaced with a ROM daughterboard, display decoding TTL chips missing on the right side, only one connector for displays (instead of two), reset board plugged into top CPU socket.

Chicago Cubs Triple Play #696, 7/85 Bounty Hunter #694, 9/85 Tag Team #698, 10/85 Rock #697, 1/86 Rock Encore #704, 5/86 Raven #702, 6/86 Hollywood Heat #703, 9/86 Genesis #705, 9/86 Gold Wings #707, 10/86 Monte Carlo #708, 1/87 Spring Break #706, 4/87 Amazon Hunt II, #684c, 5/87 Arena #709, 6/87 Victory #710, 10/87 Diamond Lady #711, 12/87 TX Sector #712, 2/88 Amazon Hunt III (kit only), #684d,

3/88 Robo-War #714, 4/88 Excalibur #715, 8/88 Bad Girls #717, 10/88 Hot Shots #718, 2/89 Big House #713, 4/89

BoneBusters Inc. #719, 8/89

System80 Board Compatibility.

System80 and System80A CPU boards can be interchanged *if* the appropriate U2 and U3 chips are used. The U2/U3 chips are the "game rules", and are different for System80 and System80A (System80B does not use chips U2/U3). Pascal Jain and www.greatplainselectronics.com both sell an adaptor board for the U2/U3 chips that allow EPROMs to be used. Unfortunately the U2/U3 are masked ROMs, so EPROMs can not be plugged directly in their place without some board modifications (see here for information on this conversion), or this adaptor board.

Making a System80B CPU board work in System80 or System80A (or vice versa), is a bit of work. The different score displays (and hence driver circuits), and the rules EPROMs are the main problems. The existing System80b display jumpers need to be removed/changed, and chips Z19, Z21, Z22, Z23, Z24, Z25 reinstalled. Also the piggyback board that replaces U2/U3 will need a new EPROM with System80 (or System80a) "game rule" code installed.

System80b CPU boards also have two PROM1 jumpers which must be configured correctly. Earlier sys80b games used a 2716 at PROM1, and later sys80b games used a 2732. The system80b CPU board must be configured correctly for either EPROM size.

E4 installed (and E3 removed) = PROM1 set for 2716 EPROM. A vertical jumper goes from pad E4 to an unlabeled pad just to the left of the resistor above pad E4.

E3 installed (and E4 removed) = PROM1 set for 2732 EPROM. Really this is a jumper going between the E3 and E4 pads.

The driver board used in all System80, System80A and System80B game is the same, and completely interchangable between all games.

The power supply board on System80 and System80A are interchangable. System80B used a completely different design, and is not interchangable with earlier games. The system80b power supply is the same as the power supply used in later System3 games (except sys80b uses .156" connectors and sys3 uses a square connector), and only provides 5 volts for the boards.

There is a total of four different System80 sound boards (with its own power supply board). Spiderman (#653) to Pink Panther (#664) used the older sound board that was simple sounds only, no speech. Mars-god of war (#666) to Ice Fever (#695) used a sound and speech board with speech as an option. The voices on this board were very crude, but typical 1980s computer voices. All System80B games (#696 to #719) used a new sound and speech board with improved speech. This board has a LED in the center for troubleshooting. The LED on this newer sound board will NOT flash until the CPU board has successfully booted. So if the system80b CPU does not boot, the sound board LED will not light or flash.

0c. Getting Started: System 80 Parts to have on-hand

Here a list of system80 parts I like to have on hand for repairs. Molex 08-52-0072 crimp-on terminal pins (for single sided connectors). Molex 08-03-0304 crimp-on terminal pins (for double sided connectors). Molex 08-52-0113 crimp-on Trifurcon terminal pins (for .156" headers). Molex 26-48-1121 .156" header pins with no lock. Cut to size. Molex 09-50-3121 .156" white housings. Cut to size. Molex 15-04-0219 .156" polarized pegs. Molex hand crimping tool for above (see here for details). Molex pin removal tool #11-03-0016. 2N6057/2N6059 (NTE247) transistor for pop bumper driver board. 2N5550 transistor for power supply. 2N5879 (or 2N5880 or 2N5883 or 2N5884) power transistor for under-

playfield. MJ2955 can also be used. MPU-U45 or CEN-U45 transistors for driver board. MPS-A13 transistors for driver board. 2N3055 (NTE130) transistor for driver board. 2N6043/TIP122/TIP102 (NTE261) transistor for driver board. 2N5550/2N5551 (NTE194) for CPU board. 2N4400/2N4401 (NTE123AP) for CPU board. 2N4403/MPS-A70 (NTE159) for CPU board. TIP31C (NTE291) for power supply UDN6118 chip for score displays. UA723CN or LM723CN chip for power supply. 7400 chip for CPU board. 7404 chip for CPU and driver board. 7448 or 74LS48 chip for CPU board. 7432 or 74LS32 chip for CPU board. 7474 chip for CPU board. 7416 or 74LS16 chip for PBDB. 74121 or 74LS121 chip for PBDB. 74175 or 74LS175 chip for driver board. 6532 RIOT chip for CPU board. 1N4738 zener Diode 8.2V, 1 Watt power supply CR7. 1N4746 zener Diode 18V, 1 Watt power supply CR6. 1N4004 diodes for coils. 1N270 diodes for switches (1N4004 can also be used). 680 ohm 1/2 watt resistor power supply R10. 12k ohm 1/2 watt resistor power supply R3. 4.7k ohm 1/4 watt resistor for under playfield transistor pull-ups. 470 ohm sealed resistor trim pot power supply. 9.1 ohm 1 watt resistor for driver board 2n3055. LEDs for power supply and other uses. 10,000 mfd 20 volt electrolytic cap for power supply. Fiberglass Pencil, good for removing battery corrosion from the CPU board.

MCM Electronics, part# SABU10191, $5.50. Also get the fiberglass refills for the pencil, part# SABU1019210, $5.50.

See the Parts Suppliers section of this web page for places to buy these parts.

0d. Before Turning the Game On: Check the Coil Resistance. A very good idea for any unknown game just purchased is to check all the coils' resistance. If the game is new to you, and you have not powered it on, a quick check of coil resistance will tell you a lot about your new game. This takes about one minute and can save you hours of repair and diagnosing work.

Any coil that has locked on (usually due to a short solenoid driver board transistor) will heat up and have a lower total resistance. This happens because the painted enamel insulation on the coil's wire burns, causing the windings to short against each other. This will lower the coil's resistance, causing the coil to get even hotter. Within a minute or so the coil becomes a dead short (less than 2 ohms), and usually blows a fuse.

If the solenoid driver board (SDB) or under-playfield mounted transistor is repaired, and the game is powered on with a dead-shorted coil, this will blow the same driver transistor(s) again when the coil is fired by the game for the first time! There is no sense making more work for yourself. So take 60 seconds and check all the coils' resistance BEFORE powering the game on for the first time.

In order to check coil resistance, put your DMM on its lowest resistance setting. Then put the DMM's red and black leads on each coil's lugs. A resistance of 2.5 ohms or greater should be seen. Anything less than 2.5 ohms, and the coil and/or driving transistor may be bad. Now remove the wire from one of the lugs of the coil, and test the coil again. If the resistance is still the same (low), the coil or diode is bad (and also perhaps the driving transistor). If the resistance is higher than 2.5 ohms, the coil is good but the solenoid driver board transistor is shorted and will need to be replaced. Lastly, the coil's 1N4004 diode could be shorted too, giving a false low coil resistance. Cut one diode leg from a coil lug and retest the coil's ohms.

Remember when reconnecting the wires to the coil that the power wire (usually two wires or thicker wires) goes to the coil's lug with the BANDED side of the diode attached. The thinner wire is the coil's return path to ground via the driver transistor and attaches to the coil lug with the non-banded side of the diode attached.

If a low resistance coil is found, also suspect the associated driver board or under-playfield mounted transistor as bad. A low resistance coil is a red flag, a warning, that there may be problems on the driver board or with an under-playfield mounted driver transistor. Actually with System80 games, if a low resistance coil is found, I can pretty much guarantee that you will need to (should) replace of course the coil, but also all the silicon devices in its ground path (under-playfield transistor, driver transistor on driver board, and any pre-driver transistor if applicable).

1a. Mandatory: Circuit Board Defects

Important note: While doing the following mandatory circuit board modifications, please inspect each board to be repaired for these defects, and correct them.

Many early System 80 boards (Haunted House and prior) had the standard Gottlieb manufacturing error of having the component leads cut too short. Gottlieb cut the leads into the solder meniscus (solder mound) that builds up around each component lead. This can cause the solder joints to crack and fail.

To correct this problem, resolder component leads where the solder meniscus has been cut. This defect is evident on both single sided and double sided circuit boards.

Look closely at this board: Can you see the plated thru holeswhere there's no solder, or the solder is "puckered"? Also note

the solder around the component pins. Some of these pins are puckeredor completely open. All these need to be re-soldered.

Another manufacturing error was that the boards were waved soldered at too low a temperature. This created problems on double sided circuit boards in the plated-thru holes. These holes let a trace move from one side of the board to the other. If these holes aren't filled with solder, this can cause intermittent connection problems. This is very common especially at holes near the edge connectors.

To correct this problem, look at the "via" (plated thru holes) and if the solder is puckered or missing (!), resolder these holes and add some new solder. To ensure complete reliability, stitch a piece of wire-wrap wire thru the holes and solder on both sides of the board.

1b. Mandatory: Power Supply Fix

These fixes are mandatory for proper long-term operation of a System 80 and 80A power supply. This information only applies to System80 and System80a power supplies (System80b power supplies are completely different). Information on repairing a dead power supply can be found at http://www.geocities.com/kirbseepe/repairpowersupply.html.

The System 80/80a Power supply, front and back views. Note the hugemetal heat sink plate the board is bolted to.

The logic ground on the power supply board also needs to be tied to the metal heat sink plate of the power supply (which will be eventually wired directly to ground for a good reliable connection). This is part of the infamous Gottlieb grounding problem, which is evident on both System80 and System1 Gottlieb games.

Gottlieb also made a mistake when designing the System 80 power supply, causing the diode CR7 to burn. They shouldn't have made this mistake; their System 1 power supply (which is almost identical to the newer System 80 design) did not have this mistake!

Many System 80 power supplies had the standard Gottlieb manufacturing error of having the component leads cut too short. Gottlieb cut the leads into the solder meniscus (solder mound) that builds up around each component lead. This can cause the solder joint to crack and fail.

Power supply solder defects.

Note the puckered solder pads.

Lastly, replacing the larger ORANGE power supply capacitor in the bottom of the cabinet is a very good idea! This will ensure the +5 vdc logic power will be nice and smooth. If this capacitor is bad, the game can reset during play. Computer grade 105 degree capacitors work great for extended life. Any value from 6800 mfd to 15000 mfd can be used, as long as the voltage is 16 volts or better. Ideally, 10,000 mfd is a good value to use. Capacitors larger than 10,000 mfd put added strain on the bridge rectifier. The "inrush" current required to initially charge the larger capacitor can prematurely destroy the bridge rectifier.

System 80B Power Supply Problems.The system80b power supply is a small board with a large heat sinked transistor, two .156" six pin Molex connectors, a resistor and cap, and a trim pot. REPLACE THE 500 OHM TRIM POT. Really no joke that pot is junk, and can cause the power supply to jump from 5.0 volts, to 7 volts, down to 4 volts (yes I have seen this happen). This can obviously play havoc with the game, and even ruin the board(s). Or replace the trim pot with a 1/2 watt resistor of about 270 ohms (non-adjustable, but there's no worry about the voltage drifting). You may have to experiment to get the correct resistor value. Measure the +5 volts on the CPU board at the input electrolytic capacitor near the +5 volt power connector, it should be 5.0 to 5.2 volts DC.

The system80b power supply also has two 6-pin .156" Molex connectors. 12 volts comes into the power supply at the lower Molex connector, and +5 volts goes out at the top Molex connector. One pin of the top 6-pin connector goes to each board in the backbox, supplying +5 volts to the boards. Because of this, the top power-out connector is often burnt. Replace the power supply board's .156" header pins. Then use Molex trifurcon pins in the plastic connector housing (the original connector housing can be reused).

Another trick is to just replace the system80b power supply with a video game switching power supply! Just hang the switcher from the inside top of the backbox, supplying +5 volts to all the wires previously attached to the top system80b power supply Molex connector. Connect ground to the ground strap in the backbox. Run 120 volt wires to power the switcher. Don't forget to adjust the switcher's +5 volt trim pot to 5.0 to 5.2 volts.

It is also a good idea to replace the 10,000 mfd 25 volt filter capacitor by the transformers and bridge rectifiers in the bottom cabinet. This cap can also be tested with a DMM set to AC volts and attached to the leads of the 10,000 mfd filter cap. If more than .50 volts AC is seen, this capacitor is worn out and should be replaced.

Testing the System80 and System80A Power Supply.

Before doing any modifications, it's good to know if the power supply (in its current state) works. Here is a good way to test a System80 and System80a power supply. Heck, if the system80 game in question has never been turned on (since you bought it!), this is a good generalized way to "bring her up", without smoke and fire.

Power Supply Test, Step One: Check all fuses in the bottom panel of the game. Make sure all are

the proper rating and type! Remove ALL connectors from ALL boards in the backbox. Attach power supply connector J1. Power the game on. Notice the two LEDs DS1 and DS2. One signifies unregulated 12 vdc

is coming into the power supply. The other LED signifies +5 volts is coming out of the power supply.

Check the output voltages at TP4 (+5), TP5 (8 vdc), TP1 (60 vdc), TP2 (42 vdc), using TP3 (ground) for a reference.

Turn the game off.

Voltages can be higher than expected. For example, seeing 48 volts for the 42 volts test point, 65 volts for the 60 volts, or 8.6 volts for the 8 volt test point are all Ok. But +5 volts should be in the 4.8 volt to 5.2 volt range (there is a trim pot to adjust the +5 volts).

Power Supply Test, Step Two:

If all voltages from 'step one' are present, continue with these steps.

Attach the connector from power supply J2 to CPU board A1-J1. Power the game on. Check the output voltages at TP4 (+5), using TP3 (ground) for a

reference. Turn the game off.

This step makes sure that the +5 volts is not dragged down by the CPU board. If +5 volts goes down, try adjusting the power supply trim pot. If voltage is still below 4.8 volts, this will need to be fixed.

Power Supply Test, Step Three:

Continue with these steps.

Attach power supply connector J3. This is the displays and playfield power connector.

Optional: Attach the CPU board connectors A1-J2 and A1-J3. These are the connectors going to the displays.

Optional: Attach CPU board connector A1-J5. This is the slam switch and test switch connector. Note: this step not required if the "slam switch mod" has been performed on the CPU board.

Power the game on. Check the output voltages at TP4 (+5), TP1 (60 vdc), TP2 (42 vdc),

TP5 (8 vdc), using TP3 (ground) for a reference. Turn the game off.

If 60 volts and/or 42 volts are now missing, there is probably a shorted score display! This is fairly common. Replace the 60 volt fuse in the bottom panel (it may or may not blow!), and disconnect all but ONE of the score display connectors (don't forget the score display in the playfield on Black Hole and Haunted House). Power the game on and check for 42 and 60 volts. Repeat this, adding one score display connector at a time, until the offending score display is found. Warning: only attach connectors with the power OFF.

Power Supply Modifications. Mandatory Parts Needed:

(1) 680 ohm, 1/2 watt resistor (for R10). (1) 12k ohm, 1/2 watt resistor (for R3). (1) 1N4738 zener Diode 8.2V, 1 Watt (for CR7). (2) Molex .156" square header pins, part# 26-48-1125, cut to size. (2) Molex .156" crimp-on connector housing, part# 09-50-3121, cut to size. (20) Molex .156" Trifurcon terminal pins, part# 08-52-0113 (Digikey part#

WM2313-ND). (1) 6800 mfd to 15,000 mfd, 16 volt (or higher) capacitor (10,000 mfd is

the ideal size to use). A computer grade 105 degree capacitor is a good replacement.

3 inches of 18 gauge wire.

Optional (but recommended) Parts Needed:

(1) 1N4746 zener Diode 18V, 1 Watt (for CR6). (1) 470 ohm sealed resistor trim pot. (2) LEDs yellow, orange or red. (1) 14 pin socket for regulator chip. (1) UA723CN regulator chip, but can use LM723CN, LM723CD, NTE923D (or

something similar since these chips are common, and Radio Shack sells these). This is used with the 14 pin socket, above.

Power Supply Disassembly Instructions:

Remove the power supply board from the head box. The board includes a large black heat sink plate behind the printed circuitry board (PCB).

Test the large metal power transistor (PMD10K40, 2N6057 or 2N6059) installed on the back plate of the board. Set the DMM to the "diode" setting. Then put the black lead on either attachment screw of the transistor (which is connected to the metal case of the transistor), and the red lead on each leg. A reading of .4 to .6 for each transistor leg should be seen. Anything else and this transistor is bad.

On the heat sink plate side, remove the 2 screws from the large transistor. On the heat sink plate side, remove the 4 screws from the corners of the

plate. De-solder the two legs of the large transistor labeled Q3. Gently pull the heat sink plate from the board.

Left: The parts to be replaced: R10, CR7, R3. Note how hot CR7 has gotten.Right: Using the solder sucker to remove Q3. Then the metal heat sink plate can

be removed, and the back of the board accessed.

Mandatory Parts Installation: Replace resistor R3 with a new 12k ohm 1/2 resistor. This resistor

often fails. Replace resistor R10 with a 680 ohm 1/2 watt resistor. This will

decrease the load on diode CR7. Check diode CR7 (the burnt part!). If damaged, replace with a new

1N4738A diode (or to be safe, just replace it). Re-solder all header connector pins (these often crack). If the

header pins are corroded or in bad shape, replace then with new .156" (square) header pins. Also replace the plastic connector housing's pins, Molex part number 08-52-0072, crimp-on pins (see the connector chapter of this document for more info).

On the solder side of the power supply board, solder a 18 gauge jumper wire from the ground trace to the lower attachment screw hole. See the picture below.

Re-solder any leads that look like they were cut too short. Re-solder the large rivet holes that the large transistor leads go

through. Solder clipped off resistor leads to the voltage test points (GND,

+5v, +8v, +42v, +60v). This will make it easier to test voltages when the board is installed.

Check the values of the other resistors on the power supply board to make sure they are in tolerance.

Replace the round metal power supply pins at connector J2 with brand new .156" Molex square header pins (Molex part# 26-48-1125, cut to size). In addition, replace the 6 pin plastic housing going to this connector with a new crimp-on variety (Molex part# 09-50-3121, cut to size). Then crimp on new .156" Molex Trifurcon terminal pins (Molex part# 08-52-0113, Digikey part# WM2313-ND) to the connector wires.

Replace the round metal power supply pins at connector J3 with brand new .156" Molex square header pins (Molex part# 26-48-1125, cut to size). Also replace the 7 pin plastic housing going to this connector with a new crimp-on variety (Molex part# 09-50-3121, cut to size). Then crimp on new .156" Molex Trifurcon terminal pins (Molex part# 08-52-0113, Digikey part# WM2313-ND) to the connector wires.

The green wire on the power supply board is solderedfrom ground to the screw attachment hole.

Left: The transistor rivet holes that need to be re-soldered. Note thecomplete lack of solder around part of the circumference.

Right: A test point after soldering a clipped-off resistor lead in place.

 

Optional Parts Installation: Highly Recommended: Replace the 500 ohm trim pot on the power supply

board. This old pot gets dirty, and the output voltage can jump around because of it. Replace with a high quality, 470 ohm unit.

Install a new 1N4746 zener diode (18 volt) for CR6. Replace the old LED's on the power supply board with new ones. With age,

the old LED's get dark and can "sink" (consume) far more current than new ones. Also change the colors of the LED's. For example, use orange or yellow LED's (but not green or blue!) so one can tell at a glance if they have been changed.

Install a 14 pin socket for the regulator chip. This regulator chip is often bad, causing the +5 volt power section to fail. Just socket the chip so the the whole power supply doesn't have to be torn apart when it goes bad.

Finishing (re-assembling) the Power Supply.

Make sure the large Q3 transistor's plastic insulator is in place. This plastic part ensures the legs of the large transistor do not short to the metal heatsink plate.

Make sure there is a mica insulator underneath the large Q3 power transistor.

Re-assemble and screw the heat sink plate back onto the PCB. Re-solder the large transistor's leads.

Using a DMM, make sure there is *no* continuity between the metal case of the large Q3 transistor and the metal heatsink plate. If there is continuity, please re-verify the above first two steps.

In the bottom of the cabinet next to the transformer, replace the ORANGE 6800 mfd 1" diameter by 3" tall power supply capacitor with a new unit. See below for more details.

Test the power supply's voltages. After doing the above mods, install the power supply board back into the game. Connect only the lower plug J1. Turn the game on. Note the two LED's on the power supply board should be lit. Using a DMM, check the DC voltages at the connectors points on the board: +60, +42, +8 and +5 volts DC. When all the voltages are present and verified, turn the game off and re-connect all the disconnected plugs. Power the game back on, and measure the +5 volts DC again. Adjust the trim pot to 5.1 volts.

2N5550 in the High Voltage section.In the high voltage section of the Gottlieb sys80/80a power supply, a 2N5550 transistor is used. If this goes bad, it can be replaced with a 2N5551 (more common and more robust). Both parts cross to NTE194.

Replace the ORANGE 6800 mfd filter cap in the bottom of the cabinet!There are two large capacitors here; replace the one WITHOUT the resistor across the leads (note on some system 80b games such as Jacks Open, Gottlieb used *two* large orange capacitors with no resistor wired in parallel, instead of just one). No exceptions here, the orange 12 volt filter capacitor(s) need to be replaced. Any value can be used from 6800 mfd to 15,000 mfd at 16 volts or higher (again on system 80b games like Jacks Open with two orange capacitors wired together, these two can be replaced with one single capacitor). Ideally, 10,000 mfd to 12,000 mfd is about right. Capacitors larger than 12,000 mfd put added strain on the bridge rectifier. The "inrush" current required to initially charge the larger capacitor can prematurely destroy the bridge rectifier.

The original capacitor can be tested (but don't bother, just replace it!) To test the capacitor, turn the game on, and set the DMM to AC volts. Put the leads of the DMM on the leads of the filter cap. If after a few seconds (after the voltages stops fluctuating) there is more than .2 volts of AC, this capacitor is bad. Again, if using

the original orange filter cap, I would highly recommend replacing it regardless of its AC reading.

Remember when hooking up the new capacitor, do *not* mix up the positive and negative wires going to the new capacitor!

Other Tips (Missing +5 volts).There are two LED's on the power supply board. One for +12 volts, and the other for +5 volts. If the +12 volts is not lit, then the +5 volts won't be either! If only missing the +5 volts, I would suspect the voltage regulator UA723CN (NTE923D) chip first, or the PMD10K40 (Q3) transistor. But hopefully Q3 was tested in the previous procedure. Make sure Q3's transistor bolts are tight, and Q3 is soldered well to it's circuit board eyelets. Also make sure there is no continuity between the metal plate and Q3's metal case.

Still no +5 volts, then check SCR1 (S107Y1). This device's job is to check turn on and short +5 volts to ground, if +5 volts goes above 6 volts (as a protection measure to the circuit boards). The SCR can be tested (with the power supply off, connectors removed) using a DMM set to diode setting. Measure between TP4 and ground (red DMM lead on ground), and .3 to .5 should be seen.

Also note power supply transistor Q1 (NPN, SW4F013) can be replaced with a TIP31c transistor. More power supply repair information can be found at http://www.geocities.com/kirbseepe/repairpowersupply.html.

System 1 Power Supply Problems.This document gennerally does not cover Gottlieb System1 games. But since the System1 power supply is so close to the System80 design, I thought it prudent to add some System1 info. See marvin3m.com/sys1 for more System1 repair info.

Make sure that Q1 is electrically isolated from the metal back plate (there is a thin mica insulator for this purpose).

If +5 volts measures 2.4 volts, then Q1 is bad. If no +5 volts, check pin 7 of IC1. This should be 14 to 15 volts (with Q1

removed). In this voltage is not 14 to 15 volts, IC1 is bad. If Q1 gets very hot and there is no +5 volts, then SCR101 is bad.

The four bridge rectifiers and two electrolytic capacitors in the bottom panel of System 80 games. The original +12 volt filter electrolytic 6800mfd capacitor is smaller and

usually orange. This needs to be replaced. This replacement is a computer grade cap.

Bridge Rectifiers.In the bottom panel of the game, there will be four bridge rectifiers and the two large electrolytic capacitors. The capacitor used for the +12 volts (and ultimately for the +5 volts) is the one that should have been replaced in the above steps. This is the capacitor without the resistor across its leads. The other capacitor smoothes the higher voltages for the solenoids, and is far less critical.

The 12 volts bridge rectifier. Notice the near left lead (orange wire) is oriented different than the other three leads. This is the DC positive output lead.

Sometimes bridge rectifiers die. If turning on your game immediately blows a fuse, this could mean a shorted bridge rectifier. For example, if the F4 fuse blows immediately at power up on Haunted House or Black Hole, this probably means the connecting bridge rectifier in the bottom cabinet has shorted.

Bridges can be tested easily. But first the leads of the bridge will need to be identified. Each bridge has four leads: two input AC leads, and two output DC leads (positive and negative). One of the legs on the bridge will be in a different orientation than the others; this is the DC positive output lead. The DC negative output lead is directly opposite (diagonal) to it. The remaining two leads are the AC input leads. Also, the two output DC leads should go to the electrolytic capacitor's positive and negative leads.

Testing a Bridge Rectifier.

To test a bridge rectifier, do this: 1. Put the DMM on diode setting. 2. Put the black lead of the DMM on the "+" (positive) terminal of the bridge. 3. Put the red lead of the DMM on either AC bridge terminal. Between .4

and .6 volts should be seen. Switch the red DMM lead to the other AC bridge terminal, and again .4 to .6 volts should be seen.

4. Put the red lead of the DMM on the "-" (negative) terminal of the bridge. 5. Put the black lead of the DMM on either AC bridge terminal. Between .4 and

.6 volts should be seen. Switch the black DMM lead to the other AC bridge terminal, and again .4 to .6 volts should be seen.

Replacing a Bridge Rectifier.If one of the bridges tests bad, replace it. Get a MB3502 or MB3504 bridge with lug leads. The "MB" specifies the type of case the bridge is in. The "35" is number of amps. The "02" means 200 volts, or "04" means 400 volts. Higher values can be used in either amps or volts. But don't go lower on either value.

1c. Mandatory: Battery Replacement/Corrosion (CPU board Reset/Clock Circuits)

The Gottlieb DataSentry battery. This battery has leaked only slightly (note the corrosion to the crystal). This board was lucky. Also shown below the battery are the Z3 (7404) and

Z2 (7474) chips. These are often affected by battery leakage.

This fix is mandatory. All Gottlieb System 80 boards use a recharagable "DataSentry" nicad 3.6 volt battery. When these batteries don't get used regularly, they can leak the alkaline potassium hydroxide and volatile gases that destroy the CPU board components and connectors. Removal of 15+ year old rechargable battery is mandatory!

Remote AA battery pack and 1N4004 blocking diode, connected to aSystem80 CPU board (original battery removed).

New BatteryTo replace the original battery, add a remote three "AA" battery pack and a 1N4001 diode (banded diode end first connected to the pcb "+" pin, and the non-banded end connected to the positive lead of the battery pack). The diode is used so the recharging circuit doesn't try to charge the AA batteries. Also the game will work fine with no battery. Not having a battery means that the high scores and operating audits won't be saved. Personally, I find this acceptable.

An installed memory back-up capacitor. After the battery is removed, the traces are sanded shiny. The negative lead of the cap is put in the negative battery hole. The

positive lead is bent, and soldered directly to the trace leading to thepositive battery hole (since the positive battery hole was too far away).

Memory Back-Up Capacitors.If one insists on having a battery (can't live without those high scores!), a decent alternative is to install a memory back-up capacitor. These capacitors will charge when the game is on, and slowly discharge to keep the memory alive when the game is off. The advantage to these capacitors is they never wear out, and they won't leak corrosive materials. The down side is the game must be on for about one hour every month to maintain their charge. Also, the game must be on for about about 8 hours continuously to initially charge the capacitor. These capacitors are about the size of a stack of nickels. Jameco (800-831-4242) sells 1 Farad memory caps, part# 142957, $3.95 each, $3.49 for ten or more.

Note that some CPU boards will work better with a memory cap than others. This has to do with the exact memory on the board, its age, and its exact manufacturing specs. Some memory chips have different power consumption rates, hence varying results can be seen with memory backup caps. Some CPU boards will maintain their memory well with a backup cap, and others may not. "Your mileage may vary" is probably a good statement about memory backup capacitors.

When I installed my back-up capacitors, the minus and positive leads were not labeled on the cap. There was only a black line on the cap to designate the negative lead (the CPU board is labeled; the positive hole has a "+" next to it).

If the installed memory cap doesn't seem to work (and it was installed correctly!), check the issolation diode CR34. Its job is to make sure the cap/battery doesn't try and power the entire CPU board when the game is off (this would drain the cap/battery quickly!) Another check is to put a voltmeter across the isolation diode CR34. There should be essentially no voltage drop across it. If about 0.7 volts DC is seen, then the system is draining the cap/battery, and it won't last long. The problem is often either a bad CR34 diode (1N4148), or a bad Z1 CMOS chip (4528). Note these parts are included in Ed's battert corrosion kit below.

Reset Circuit Check.The reset circuit is the most vulnurable part of the CPU board in regards to battery corrosion. To determine if the reset circuit is working on a CPU board is pretty easy. Connect the CPU board to +5 volts (the left most CPU board 5 pin connector), and then check the 6502 pin 40 for +5 volts. If this pin is 0 volts, the reset circuit is not working. If 6502 pin 40 is 5 volts, then the reset circuit is working. Remember the purpose of the reset circuit is to hold the 6502 microprocessor's reset line pin 40 LOW (0 volts) for about 100 milliseconds. This allows the +5 volts to stablize at power-on. Then the reset circuit makes 6502 pin 40 go HIGH (to 5 volts), and the 6502 processor starts running and executing game code (and the game "boots"). So if the reset circuit is not working, the CPU board will never boot (never start executing ROM code), even if the rest of the board is fine. After the reset circuit is working, the next thing you should check on a dead CPU board is the clock signal (again, this circuit is right around the battery). See the Sys80 CPU board Repair section for more info.

Battery Corrosion and the CPU Board's Reset/Clock Circuits.Battery corrosion can do nasty things to the left side of the CPU board. This is the "reset" section of the CPU board (and below the crystal Y1 is the "clock" section). Depending on how bad the corrosion is, many parts may be needed in these areas. Instead of ordering all those separately, I suggest just buying a "Gottlieb System80 Battery Corrosion Repair Kit" GTLB80-BA-KIT from greatplainselectronics.com. This kit includes all the resistors, capacitors, transistors, crystal and chips typically ruined by battery corrosion. For a mere $10 (plus $3.50 shipping), this kit is well worth it. If for some reason the $10 is too much money, here are the typical parts needed for a System80 battery corrosion repair (these are the same parts included in Ed's kit):

Z1*: CMOS 4528. Z2*: 7474 or 74HCT74 chip. Z3*: 7404 chip. Z4*: CMOS 4081. Z36*: 4069 CMOS chip. (4) 14 pin sockets for Z2,Z3,Z4,Z36 chips. (1) 16 pin sockets for Z1. SW1: 8 position DIP switch C1*: 100 mfd 10 volt electrolytic cap. C2,C5: .01 mfd (103) ceramic cap. C3,C25: .1 mfd (104) ceramic cap. C36*: 10 mfd 10 volt tantalum or electrolytic cap. CR1-CR8,CR33-CR35*: 1N4148 or 1N914 diode. R3,R43,R49: 5.6k ohm 1/4 watt resistor (green, blue, red). R4,R5,R44: 2k ohm 1/4 watt resistor (red, black, red). R6,R45,R46,R48: 3k 1/4 watt resistor (orange, black, red). R7: 62 ohm 1/4 watt resistor (blue, red, black). R8,R50: 180 ohm 1/4 watt resistor (brown, gray, brown). R9: 1k ohm 1/4 watt resistor (brown, black, red). R34-R41, R54: 4.7k ohm 1/4 watt resistor (yellow, purple, red). R47: 24k ohm 1/4 watt resistor (red, yellow, orange). Q1,Q4*: MPS-A70 or 2N4403 transistor. Q2,Q3*: 2N4400 or 2N4401 transistor. VR1*: 1N5225b or 1N5987b zener 3 volt diode. Y1: 3.579545 mHz crystal.

* Polarized parts: The above components DO require installation in the "correct direction". Failure to do so will kill the part, and maybe some other parts too. And for sure the board will not work. So be careful!

Using a Dallas/Maxim DS1811 in the Reset Section.Thanks to Pascal Janin, there is also another way to fix the reset section with just a four parts (that replaces nearly 25 parts!) This involves using the new Dallas/Maxim Semiconductor D1811 reset chip (TO-92 package). This inexpensive device looks like a transistor, but is really a three leg chip in a TO-92 transistor package. Click here or here (PDF, more info) for the specs on this chip. Cost of this chip is less than $1, and can be ordered directly from Dallas/Maxim Semiconductor at www.dalsemi.com via their phone number 888-629-4642 (but orders must be faxed in at 408-222-7174). Be sure to order the TO-92 package (part number DS1811-10), as this chip also comes in a surface mount SOT23 package.

The advantage to the Dallas DS1811 is great: if a system80 CPU board has had some battery corrosion and perhaps some circuit board traces are questionable, the new Dallas part will not utilize most of that. So even a board with lots of corrosion can have 25 reset parts cut out, and just the Dallas installed. So most of the questionable traces on the component side of the circuit board are eliminated too, making battery corrosion less of an issue.

The Dallas DS1811 comes in three TO-92 flavors of "normal reset threshold":

DS1811-15 = 4.13v DS1811-10 = 4.35v * DS1811-5 = 4.62v

* The best one to order is DS1811-10.

Here are the installation steps for this chip:

Remove reset parts: chip Z1, trans Q1-Q4, diodes CR33, CR35, VR1, resistors R8, R9, R43-R50, caps C2, C25, C36.

Install a jumper from Z1 pin 5 to Z1 pin 9. Install a jumper from Z1 pin 11 to Z1 pin 13. Be careful not to accidentally

connect pin 12 to the jumper, as it will cause the reset modification to not work.

Install a jumper where R45 was installed. Install a jumper between the two top holes of Q3 (the Emitter and Base). Install the Dallas DS1811 (TO-92 package) into the top pads of R50, R44,

R49 (pin 1=R50, pin 2=R44, pin 3=R49). Note the flat edge of the DS1811 faces downward away from Z1, toward the dip switches.

Retain reset parts CR34, R7 and C3. Note R10 and C14 can be remove or left installed. Since Z1 has been

removed, R10 and C14 are no longer used, and can be removed (or left installed).

The DS1811 is installed with pin 1 going to /RESET, pin 2 to +5 volts (thanks to the jumper at R45), and pin 3 to ground (via the jumpered Q3). A picture of all the removed parts and the DS1811 and jumpers installed can be seen below. Also remember using the DS1811 will not replace the often damaged clock circuit chips at Z2 and Z3.

Picture of the Dallas DS1811 installed in the Sys80 CPU board.

The Dallas DS1811 installed in the Sys80 CPU board (picture by Neil Bradley).

Another picture of the Dallas DS1811 installed in the Sys80 CPU board.

There is a side affect of the changed reset circuit: the "thunk" that is often heard at boot up on System80 games may be louder, because the reset timing is changed. The duration of the reset pulse issued by the DS1811 lasts 150ms, while the original circuitry generates a 50ms reset. This increases the startup time until the coil and lamp outputs are properly initialized, hence the slightly harder "thunk". Personally I don't really think the "thunk" is louder, but it could be different on your game.

Removing the Old Battery and Fixing Corrosion.

Here are the battery corrosion repair steps:

1. Remove the CPU board from the head box. 2. De-solder the four leads to the "Data Sentry" (rectangular black plastic)

battery. Remove the battery and discard. 3. If any components are damaged by the battery (look for green and/or

gray!), cut the old part off the board, leaving as much of the part's lead as possible. Heat the solder pad on the circuit board with a soldering iron, and pull the cut off lead out of the board. If the lead is not coming out easily, add some new solder to the solder pad. This will help distribute the heat. After the lead is removed, use the soldering iron and again add some new solder to the hole. Then use a solder sucker (Soldapulit) and de-solder the hole.

4. If there is any gray or greening of a part's leads, replace it. If in doubt, replace it. To be completely safe, replace all the parts included in the list above (especially if Ed's kit was purchased). At a minimum, typically transistors Q2, Q3, Q4 and all the resistors around that area are damaged. Also chips Z2 and Z3 and the crystal Y1 are often damaged.

5. Check the edge connector fingers (pins) for "green". If the metal pins are green, they will need to be replaced!

6. After removing the damaged components, sand all green/gray areas of the board with 220 grit sandpaper, including edge connector fingers. Sand until the copper is bright, which will allow solder to stick.

7. Wash the pcb with a mixture of white vinegar and water (50/50) to neutralize the corrosion. Scrub with a toothbrush. This is very important! If this step is skipped, the corrosion will return.

8. Rinse the washed board with clean water. 9. Rinse the board with 99% pure alcohol. This will dissolve and wash away

the water. Repeat this step. The alcohol will evaporate quickly. 10. If sanding the edge connector fingers, heat them with your soldering iron

and tin them with solder. Wipe with a cloth while still hot to smooth and remove the excess solder. This can also be done to any traces sanded on the board.

11. Replace all removed components (except the battery!). Any removed chips should be replaced with a good quality socket.

12. Check the connectors themselves! If the board has corrosion, the connectors may too! Replace the connector pins if any damage is seen (see the connector section below). They can also be cleaned sometimes with scotchbrite and alcohol. But replacement is the ideal solution.

Again, order the battery corrosion kit from Ed to get all the parts usually ruined by corrosion.

1d. Mandatory: Ground Problem Fix/Upgrade

These fixes are mandatory.

Driver board parts that are required:

(4) Molex connector pins for the A3-J1/A1-J4 connector (mandatory). See the next section for part numbers.

(10) feet of 18 gauge wire (mandatory) Wire wrap wire (30 gauge) or zero ohm resistors (optional)

Other driver board stuff to have around that is often bad:

MPS-U45 transistors MPS-A13 transistors 2N3055 transistors (and connecting 9.1 ohm resistor) 2N6043 transistors

The Gottlieb Grounding Problem.There are multiple problems with ground in System80 games. One problem relates to differences in ground between the CPU board and the Driver board. The other problem relates to differences in ground between the circuit boards and cabinet ground. We address and fix both problems below.

First there is the problem with ground between *cabinet* ground, and circuit board ground. John Robertson documented this problem back in 1987. There is a single ground connection between the cabinet ground and circuit board ground on the power supply. If this single connection has resistance (which is common on older games), problems occur. This resistance, with the current drawn by the Driver board through the power supply, causes a voltage shift in the power supply's ground line. If the voltage shift get up to .5 volts relative to the cabinet ground, the solenoid driver transistors are no longer biased off, and start to conduct. This can cause playfield coils to "lock on" and burn, damaging the coil and its associated driver transistor. This single problem made many people think Gottlieb system80 games were "unreliable".

Now let's talk about the Driver board and its multiple grounds. There are several grounds on the Driver board (lamp ground, logic ground, solenoid ground, etc). Only the solenoid ground should be independent (as it was designed), and all other grounds should be tied together. The logic ground levels between the CPU and driver boards also need to be equalized (as little difference as possible between the two). Because ground between the boards are connected via a single edge connector wire, differences in ground levels can occur. If resistance develops in the connector (very common), and the difference between the logic ground on the CPU and driver board is .1 volts or higher, the CPU and/or Driver board can lock up and be damaged. This in turn can cause coils to lock on and burn. Though this is less of a problem than the cabinet and circuit board ground (see above), it is still a problem.

Prior to 12/1/99, there was a slightly different procedure in this guide for fixing the driver board ground problems. Thanks to Pascal Janin, we now have a better understanding of the problem. He documented the differences in voltages in the following places:

Difference in voltage between the negative side of capacitor C1 (100 mfd 10v) and the connector A1J4 pin A, on the CPU board.

Difference in voltage between the negative side of capacitor C1 (100 mfd 10v) on the CPU board and chip Z12 pin 8 on the Driver board (the furthest away ground connection).

Difference in voltage between the positive side of capacitor C1 (100 mfd 10v) and connector A1J4 pin B, on the CPU board.

Difference in voltage between the negative side of capacitor C1 (100 mfd 10v) on the CPU board and chip Z12 pin 16 on the Driver board (the furthest away +5 volt connection).

Ideally, as little difference in voltage as possible is desired. Pascal tested this with no modifications, the earlier modification (previously described here), and the new modifications (described below). The methods now documented here yielded the least amount of variance in the voltages.

These modifications also ensures that the solenoid ground is independent from the logic ground. This is important because if the solenoid ground fails, the solenoid high voltage could go through the logic ground, damaging circuit board components. Also, there can be "feedback" interference to the logic ground from the solenoids. This could damage circuit board components.

What are We Trying to Accomplish?

In the "mandatory" ground modification, we make sure the cabinet ground and circuit board ground are solidly tied together (the connection to ground between the cabinet, power supply, CPU and Driver board, and other boards will be made more reliable). In the "optional" ground modification, we make sure the solenoid ground is isolated from the logic ground so that all the solenoid transistors on the driver board (except Q57, Q61, Q63) will have their emitters connected together. But in addition, these solenoid transistor grounds will be isolated from the CPU and Driver board logic grounds (a good place to test for logic ground is at pin 8 of any 74175 chip on the driver board).

The Gottlieb System 80 Driver board, with added ground wire.

The Gottlieb System 80b CPU board, with added ground wire and a remote battery pack.

Mandatory Ground Modifications Steps.

1. PRE-WORK: Test all the driver board transistors. This only takes a few minutes since the Driver board is already removed. If any test bad, replace them now to prevent future problems. See the Testing Transistor with the Driver board Removed section for info on how to do this. Do NOT skip this step! If the driver board is out of the game, it only take a moment to test all the transistors.

2. STEP 1: On the CPU board, find the electrolytic capacitor C1 directly to the right of the main CPU power connector A1-J1. Attach a 12" wire to the TOP lead of this C1 capacitor, and a forked spade connector on the other end of the wire. This wire is the CPU ground.

On Sys80/Sys80A, run this added CPU board ground wire to the metal frame of the power supply.

On Sys80B, run this added CPU board ground wire to the ground plane screw (which attaches to the yellow covered ground plane) in the lower right of the backbox.

Step 1. Sys80/80a ground from power supply capacitor C1's negative lead, to the metalframe of the power supply. And the ground from the CPU board's electrolytic capacitorC1 negative lead to the metal frame of the power supply. Picture by J.Robertson.

EMBED Word.Picture.8

Note: Remember how we modified the sys80/sys80a power supply to connect ground with a jumper wire to the metal heat sink plate, in the Power Supply modification section? Well here's where that modification ties into the CPU ground. If this power supply modification step was not done, a wire can be connected from the power supply's negative lead of capacitor C1 (large electrolytic cap at the lower left corner of power supply), to the metal heat sink power supply frame connection. If the black part of the power supply frame is used, be sure to SAND the black off the frame where the wire connects to ensure a good connection.

On system80 and sys80a, connect the ground wire from the CPU board to one of the mounting bolts on the metal power supply board heat sink plate frame (use a "fork" or "bullet" connector so the CPU board can be easily disconnected). Again if the black part of the power supply frame is used, be sure to SAND the black off the frame where the wire connects to ensure a good connection. Then continue this wire to the metal lock plate in the upper left corner of the backbox. This metal lock plate also has a stock green wire (provided by Gottlieb), which continues down to the to the large copper ground bus in the bottom panel of the game (where all the green wires are soldered), next to the transformer. This is the main ground bus for the game. Optionally another wire can be added from the lock plate/metal power supply plate down to the copper ground strap (be sure to sand this copper ground area clean before trying to solder to it). Also note on some System80 games the 6 volt GI (general illumination) line runs dangerously close to the power supply frame. Make sure the bare 6 volt GI wires do *not* touch the power supply frame.

Step 1. On sys80 and sys80a, if the power supply board ground to the screw attachment hole wire

modification documented above is not done, a ground wire can be soldered to the negative lead of the power supply capacitor C1. The other end of this wire

and then attached to the metal ground frame of the power supply.

Step 1. This pictures shows the bottom panel of the game, and the large copper grounding strap (with all the green ground wires connected). The green ground wire attachs to the CPU and Power supply boards here.

Picture by J.Robertson.

2. STEP 2: Replace the power supply to CPU board power connector cable pins (all sys80,a,b games). On the CPU board connector A1-J1 to the power supply connector J2, replace *all* the pins on both connectors! On sys80 and sys80a, it

involves replacing the round male power supply header pins at power supply connector J2 with brand new .156" Molex square header pins (Molex part# 26-48-1125, cut to size). Also replace the 6 pin .156" plastic housing with a new crimp-on variety (Molex part# 09-50-3121, cut to size). Then crimp on new .156" Molex *Trifurcon* terminal pins (Molex part# 08-52-0113, Digikey part# WM2313-ND) to the wire. On all sys80,a,b game on the CPU A1-J1 connector, replace the five pins with brand new Molex single sided terminal pins (Molex #08-52-0072). The original plastic connector housing can be re-used.

3. STEP 3: For sys80/sys80a, on the power supply connector J3 (which supplies the display voltages and display grounds), replace the entire header connector. This involves replacing the round metal power supply pins at connector J3 with brand new .156" Molex square header pins (Molex part# 26-48-1125, cut to size). Also replace the 7 pin plastic housing with a new crimp-on variety. Then crimp on new .156" Molex *Trifurcon* terminal pins (Molex part# 08-52-0113, Digikey part# WM2313-ND) to the wire. If this connector is not rebuilt, a "low-rent" modification can be preformed. Run a wire from pins 4/5 of power supply connector J3 to the metal frame of the power supply (don't forget to sand the black part of the power supply frame where any wire attaches). If this modification is not done, score display "flicker" can result (especially on any displays that are playfield mounted), and sporatic pop bumper problems (either not working at all or working strangely).

For Sys80B, some ground modifications must be done at the lower cabinet on the metal transformer panel. On one side of this panel are several 9 pin connectors with white wires. These are the ground wires which connect to the metal housing the transformer panel. Often the part of the connector with the male pins bolted to the side of the metal panel crack. At minimum these should be removed, inspected, and resoldered. If one pin's solder joint cracks, the wire that connects to that pin will lose its ground path! This is a very bad thing. To really bullet-proof this design, all the ground wires can be shorted together BEFORE going to this connector. That way if one pin cracks, it's no big deal, as the other pins take the load.

On Sys80B another thing that must be done is to resolder the .156" J1 and J2 connector male header pins on the power supply board. There are only two connectors on this board, and it is very common for these to have cracked solder joints around the pins (giving intermittent power/ground paths).

And on Sys80B power supply, while you're resoldering the header pins, attach a ground wire to the bottom J1 pins 1,2 (ground). Run this wire to the yellow ground plane bolt at the bottom right side of the backbox.

Step 3 on Sys80b,resolder the power supply header pins and add a ground wire to J1 pins 1,2.

Step 3 On sys80B, find the 9 pin ground plugs on the side of the transformer metal panel.

Remove the connectors, and then remove the two 1/4" hex bolts that hold themale pins to the side of the transformer panel. On the back side of thesesmall connector PCBs, resolder the pins as the solder joints like to crack.

Here's the System80b ground PCB removed from the side of the transformer panel.

Cracked solder joints can be seen here (resolder these).

In the future to prevent a single cracked solder joint pin from effectinga ground, all the ground wires can be tied together before the connector.

4. STEP 4: On all sys80,sys80a,sys80b games, on the connector CPU A1-J4 to Driver board A3-J1 (that goes from the Driver board to the CPU board), double-up the Ground and +5 volt lines (note on some system80b games this may have been done by the factory). Order Molex terminal series 4366, part #08-03-0304 (for 18 gauge wire). Crimp and/or solder the new pins to some wire (see the

following section on connectors for how to do this). If not using new pins, often old video game harness edge connector pins can be used. Or use pins from a new JAMMA video harness (about $15). Either way, remove four pins and their wire from the video game harness using a 5 watt resistor with one lead cut to 3/8" long. Insert the 3/8" long lead into the top of the old video game connector, between the pin and the plastic wall. Gently pull the wire to remove the pin.

Insert two pins and wires into the A3-J1 Driver board connector at the back side, far right (as facing the installed boards).

Insert the other two pins and wires into the A1-J4 CPU board connector at the front side, far right (as facing the installed boards).

Splice the two outside wires from A1-J4 and A3-J1 together (ground). Splice the other two inside wires from A1-J4 and A3-J1 together (+5 volts

DC).

Now the pins are doubled up and have reliable +5 volts DC and ground contacts from the CPU board to the Driver board. One can also buy a new connector that already has this modification done. They are gold plated and have two +5 and two ground pins. This is available from Docent Electronics at 937-253-2768, $25.00 plus shipping.

Note: Double sided connectors (A3-J3 in this case) use numbers for the pins on the front (component) side of the board, and letters for the pins on the back (solder) side of the board. Some letters are not used because they look too much like numbers. These include: G, I, O, Q. If more than 22 pins are used, a "bar" is designated over the repeated letters. For example, pin 23 (where pin 22 = Z) on the back side of the board would be designated as "/A".

5. STEP 5: Run a ground wire directly to the Solenoid Driver board. Just below chip Z10 on the solenoid driver board there is a large, thick trace, which connectos to Z10, Z11, Z7, Z5, Z3, Z1 pin 7. Scrape the solder mask from this trace and attach a 18" wire. Be careful not to short the wire to the row of resistors beneath this large trace, or the smaller trace above it (which connects to Z2 pin 11). Alternatively there is a vertically mounted capacitor on the upper right side of the driver board - connect the ground wire to the lower lead of this cap. On the other end of the wire attach a "fork" connector. Connect the fork connector to the metal frame of the power supply. If doing this on a system80b game, connect the ground wire to the ground plane bolt in the upper right corner of the backbox.

Step 5. Attaching a ground wire to the solenoid driver board below Z10. Picture by J.Robertson.

6. STEP 6: If the game has an Auxiliary Lamp Driver board (Haunted House, Black Hole, Volcano, Mars God of War, etc.), run a ground wire to this lamp board. The Auxiliary Lamp board is used for the marquee lights in the backbox of a handful of system80 games. If the ground is unreliable to this board, the score displays can flicker and act strange. Scrape the green solder mask from the large circuit board trace between the lower left chip and the MPS-U45 transistors at the edge of the board. Solder a wire to this trace, then continue the wire to the metal power supply frame to complete the ground path.

Step 7. Attaching a ground wire to the chaser light board as used on HauntedHouse, Black Hole, and some other system80 games. Picture by J.Robertson.

7. STEP 7: If the game has a sound/speech power supply board, add a ground wire to this. On the back (solder side) of the board there is a large trace running around the edge of the board. Scrape the solder mask from this trace and attach an 18" piece of wire to this trace. Then continue the wire to the metal power supply frame to complete the ground path.

Step 8. Attaching a ground wire to the sound/speech power supplyboard as used on some system80 games. Picture by J.Robertson.

8. STEP 8 (Sys80B only). The ground wire going to the power supply module connector J1 pin 2 (bottom conector, white wire) needs a second wire attached to this pin for an added ground. Remove the J1 pin 2 from the connector housing, and crimp on a new .156" Trifurcon connector pin, adding a second wire to this pin. Then run this wire to the upper right corner of the backbox and attach to the ground plane screw.

At this point, the mandatory grounding modifications are done.

System80B Raven backbox with the mandatory ground mods and remote battery pack installed.

Optional Ground Modifications Steps.

The grounding modifications can be taken one step further. The following will tie all grounds on the driver board together, except for the solenoid ground (which will be isolated to protect the circuit boards from solenoid feedback to the logic ground).

If you do not have much circuit board repair experence, it may be a good idea to skip these steps. Though the following solves some driver board ground problems, these mods are not nearly as important as the above "manadatory" cabinet ground to circuit board ground modifications.

IMPORTANT: a note about "Wire Wrap" used in this procedure.Through out this procedure, small 30 gauge blue wire can be seen, which is used for all ground modifications. This wire is known as "wire wrap". I used this type of wire in the pictures below because it's easy to work with (and does "clean" modifications), and it shows up great in the pictures. BUT in reality, it is probably

too small for these ground modifications! I highly suggest using thicker wire (such as cut off resistor leads), or double/triple up the wire wrap on each of the connections shown below. There is a potential for up to 8 amps to go through these added connections. Wire wrap will vaporize at about 3 amps.

Note: for the fixes on the driver board I have the board positioned so the "bottom" is the edge with the J4 edge connector. Likewise for the CPU board, the board is positioned as it would be installed in the game with connectors J4, J5, J6 at the "bottom".

1. Remove the three metal cased power transistors Q58, Q62, and Q64 (2N3055) from the driver board:

Each transistor has two screws. Remove these screws. De-solder the two transistor leads for each of the three power transistors. Notice the thin mica insulator for all three transistors. Cut the mica

insulator so the bottom screw (the screw the leads are closest to) is not covered by the mica.

On the component side of the driver board, tin the bottom screw contacts for all three transistors. Note this is the contact that leads to ground (the upper contact has no traces attached to it).

Test the removed transistors (2N3055). Set the DMM to the "diode" setting. Put the black lead on the metal case of the 2N3055, and the red lead on each leg. A reading of .4 to .6 for one leg, and no reading for the other leg should be seen. Now put the red lead on the "base" lead (see picture below) of the transistor. Put the black lead on the other leg (emitter), and then the metal case of the transistor (collector). A reading of .4 to .6 should be seen with the black lead on the emitter or collector. Any other readings and this transistor is bad and needs replacing (they are about $1 each at Radio Shack).

Re-assemble the transistors and make sure to crank the screws down tight. Resolder the transistor leads to the board.

Check the three BIG 1 watt 9.1 ohm resistors connecting to the 2n3055 transistor. These should be 9 or 10 ohms in circuit.

The metal case of the power transistors should now make excellent contact to ground.

Step 1: A removed driver board transistor from Q58 with the mica insulator modified. Also thebottom mounting hole has been tinned withsolder for better contact on the driver board.

Steps 2 on the driver board.

2. On the component side of the driver board at connector J5 pin 3, there is a via (plated through hole). There is also another via just under transistor Q59's left most leg. Connect these two vias together with wire.

Steps 3, 4 at driver board connector J4.

3. On the solder side of the driver board, note the vias at connector J4 (bottom right solder side of board). From the solder side with connector J4 at the bottom, pins are numbered from the left (note there is a "1" screened on the board at pin 1). At J4 pins 9,10,11,14 (solenoid grounds) scrape the green solder mask from the board from the bottom most trace immediately above the pins - this trace goes to

J4 pin 15, which is ground. Run some wire through the pins 9,10,11,14 vias and solder them all to this ground trace (pin 15). Note tying J4 pin 5 (lamp ground) to this solenoid ground trace was removed from this step 12/18/03 because tying the lamp ground to the solenoid ground is not correct.

4. On the solder side of the driver board, locate J4 pin 5 (lamp ground). Solder a jumper from J4 pin 5 (lamp ground) to the via that is 3/4" above J4 pin 6 (another lamp ground which attaches to J3 pin C). This jumper attaches two lamp grounds together.

Step 5 on the driver board.

5. On the solder side of the driver board, solder a wire from the trace that connects to the right most pin (emitter) of transistor Q43, to the trace that connects to the bottom most pin (emitter) of transistor Q51. If either of these transistors are replaced in the future, make sure to maintain this jump.

Steps 6, 7, 8, 9 driver board solder side view.

6. On the solder side of the driver board along the lower edge (about 3" from the left and just above connector J3), there is a large "Y" or "T" shaped trace. This trace originates at pin U (letters are used to label pins on the solder side for double sided connectors; 4th pin from the left) of connector J3, and is directly above the label "J3" on the board. Scrap the green solder mask from this thick trace, just below transistor Q23. Now connect the lower pin (emitter) of Q23 to this thick trace. If this transistor is replaced in the future, make sure to maintain this jump.

7. On the solder side of the driver board, solder a wire from the right most pin (emitter) of transistor Q9, and connect it to the thick "Y" trace. If this transistor is replaced in the future, make sure to maintain this jump.

8. On the solder side of the driver board, solder another wire to the thick "Y" trace just soldered in the previous step. Just to the right of this, scrape the green solder mask off the two traces that connect to pins 9 and pins 11 of the J3 connector (as counted from the left). Connect the other end of the wire to both of these traces.

9. On the solder side of the driver board, find transistor Q25. Scrape the green solder mask on the trace just below the Q25 emitter (lowest pin closest to the bottom edge connectors). Connect Q25's emitter to this trace. Usually there is enough lead on the transistor to use this as a jumper to the ground trace. If this transistor is replaced in the future, make sure to maintain this jump.

Step 10 on the driver board.

10. On the component side of the driver board, cut the large trace in the lower left corner that goes to connector J5 pin 15, and goes around the large transistor Q64 and the

"hole" in the circuit board (this was a design error). NOTE: most driver board test fixtures will *not* work after this trace is cut! So this modification should be reversed if this driver board is sent in for repair.

Step 11 on the driver board.

11. On the solder side of the driver board, find the bottom pin (emitter) of transistor Q56. Using wire, connect a jumper to the via that is 1/2 inch below and to the left of Q56. Continue this jumper to the large trace that connects to the bottom pin of Q54.

12. Examine the rest of the driver board: Any unsoldered vias should be soldered. Any puckered vias should be re-soldered. Examine the soldered components too. Any component leads that do not cover their pad should be re-soldered. Any cut solder meniscus (mounds) should be re-soldered also.

The optional driver board modification are now complete.

Score Display Grounds (flickering displays).There is yet another ground issue that needs to be addressed, and this relates to the score displays in system80 games. Often the score displays will flicker. As John Robertson has documented, it turns out that the common return path for the displays comes in two separate lines back to the power supply. Making a simple short between the two pairs of display ground wires solves intermittent pin connection failures on the score displays. This simple fix often solves score display flickering. Also on games with a playfield mounted score display (Haunted House, Black Hole, etc), the ground to these score displays can be intermittent also, causing these displays to flicker.

System80 Games with Auxiliary Lamp Driver Boards.Another problem with score displays exists on games with auxiliary lamp driver boards (like on Haunted House and Black Hole). The auxiliary lamp driver board controls the lighting effects in the backglass. Sometimes the score displays can be seen flickering to the beat of the backbox lighting affects (which are controlled by the Auxiliary Lamp driver board). Unplugging the Auxiliary Lamp driver board can show the displays no longer flash or flicker. This can be especially a problem with the score displays mounted in close proximity to the Auxiliary Lamp driver board on Haunted House. The solution to this problem is the run an additional ground path to the Auxiliary Lamp driver board, using the updated ground path enforced

in the above sections. Also check the back of the Auxiliary Lamp driver board for cold or open solder joints.

Random Pop Bumper Problems (Bad Pop Bumper Grounds).Yet another ground issue on many system80 games is the ground path for the pop bumper driver boards. Often pop bumpers will work intermittently, or will fire when a ball is no where near the pop bumper in question. This problem is due to a bad ground path to the under-the-playfield pop bumper driver boards. There is but one pin on the MPU board that brings the ground path to the pop bumper boards. If this one pin is intermittent, pop bumper problems will happen. Again the solution is to "double up" the ground path from the pop bumper driver boards to the grounds reinforced above in the backbox.

Replace the Electrolytic Capacitors on the MPU and Driver boards.Another "good idea" is to replace the (probably) dried-out electrolytic capactors on the MPU and driver boards. This includes C1 on both the CPU and driver board (used for power supply decoupling), and C36 on the MPU board (used for the initial power on delay).

1e. Mandatory: Connector Problems

Parts and Tools needed:

Molex card edge pin extraction tool, part# 11-03-0016. Hand Crimping Tool: Molex WHT-1921 (part# 11-01-0015), Molex part#

63811-1000, Amp 725, or Radio Shack #64-410. Molex connector pins. See below. Molex connector bodies (the plastic part that holds the pins). Optional, as

sometime the original connector body can be reused. See below.

Connector/Board Numbering.Connectors are numbered in this fashion: the first "A" letter/number combination denotes which board the connector belongs. That is, A1 is the CPU board, A3 is the driver board, etc. After the board designation, the "J" letter/number combination is the actually connector number for that board. So "A1-J3" is board A1's (CPU board) J3 connector (note some Gottlieb documentation does not put a "dash" between the board and connector numbers). Below are a list of "A" numbers (applies to most system80 games, but not all):

A1 = CPU (controller) board. A2 = Power supply board. A3 = Driver board. A4 = Score display boards. A5 = Status digit display board (4 digits). A6 = Sound/speech board. A7 = Sound/speech power supply board. A8 = Pop bumper driver board(s). A11 = Auxiliary lamp driver board.

Insulation Displacement Connectors (IDC) Card Edge Connectors.All Gottlieb System 80 games use card edge Insulation Displacement Connectors (IDC). IDC means that the connector has a "V top" metal pin that a wire is pushed into. This "V" cuts the insulation allowing the pin to make contact with the wire. The IDC style of connector is still used by most pinball manufacturers today. They allow fast and easy wire connection without any soldering. There are also some crimped style connector pins in system80 games. This is a much better design than IDC connector pins because the wires attach better to the pins.

All pinball manufacturers have stopped using card edge connectors, as used on System 80 games, in favor of header pin connectors. Header pin connectors have the advantage of allowing multiple wipers per pin, less pin fatigue, and easier replacement (on both the board and connector housing). This gives better long-term reliability.

Battery Corrosion and Connectors.If there are battery corrosion problems, these card edge IDC connectors just magnify the problem (and sometimes allow the leaking battery electrolyte to travel thru the connectors to other boards!). Inspect the connectors and board edge "fingers". If corrosion is visible on the board, clean the edge fingers by lightly sanding the corrosion with 220 grit sand paper to remove it. After the corrosion is removed, wash the circuit board in a 50/50 mix of white vinegar and water. Use an old toothbrush to wash the board with the vinegar mix. Then rinse the board with clean water. Finally rinse the board with 99% alcohol, and allow it to air dry.

If the board's connector fingers were sanded, use a soldering iron and some rosin flux to re-tin the connector fingers with solder. Also the connector housing connector pins

should be replaced. At minimum, clean these connectors with alcohol and a Q-tip. If the connector pins have any corrosion (the pins are not shiny, but have a dull grey or green appearance), they must be replaced.

An "official" Molex card edge pin extraction tool.A far better Molex extractor is part number 11-03-0016

(this tool is part number 11-01-0014).

CPU Board Connector Types.Here is a list of the connectors used on the system80 CPU board. The CPU board connectors are listed because these are the ones affect by battery corrosion the most. The connectors on the power supply, sound board and driver board are much less affect by corrosion, and hence may not need to be replaced.

A1-J1: Edge connector, crimp pin style, 5 pin, single sided, 18 guage wire. Main power connector from power supply, upper left side of CPU board.

A1-J2: Edge connector, IDC, 24 pin, single sided connector. Score display segments, right side of CPU board.

A1-J3: Edge connector, IDC, 17 pin, single sided connector. Score display digit strobes, right side of CPU board.

A1-J4 (to A3-J1): Edge connector, crimp pin style, 24 pin (per side), 48 pins total, double sided connector. CPU to driver board connector (solenoid, sound and lamp controls), bottom side of CPU and top side of Driver boards.

A1-J5: Edge connector, IDC, 10 pin, single sided connector. Switch matrix strobes (to the playfield), bottom side of CPU board.

A1-J6: Edge connector, IDC, 19 pin, single sided connector. Switch matrix returns (to the playfield), bottom side of CPU board.

Location of the connectors is important. Since the battery is on the left side of the CPU board, the CPU connectors around and below the battery often need to be replaced. This includes CPU connectors J1 (upper left edge), and J4, J5, J6 (bottom edge of CPU board).

Crimp-on Replacment Connector Housings and Pins.On the CPU board, the non-IDC connectors can have new connector pins installed into the current plastic connector housing. This includes CPU connector J1 and J4 only.

Also, the remaining CPU IDC connectors (J2, J3, J5, J6) should ideally be replaced in their entirety, including the plastic housing, and converted to crimp-on style pins. Unfortunately, these card edge crimp-on connectors housings are very difficult to find. Therefore, crimp-on style pins can be installed into the old IDC connector housings, with some minor modifications.

Connector (terminal) pins will be required, but Molex connector pins are somewhat difficult to order, as there are so many different varieties. Note the "chain" variety are not wanted, unless the "loose" variety is not available (the chain type may be cut with a sharp pair of scissors). The chained variety are designed for high-speed installation machines, not single use. Purchase only phosphor-bronze tin plated pins (do not use gold pins).

Molex Replacement Connectors for System80 CPU

Connector Type HousingSeries

HousingPart# Wire Gauge Pin Series Pin Part#

A1-J1*main power

5 Pinone sided 2574 09-01-7051 18 - 20

22 - 2624782578

08-52-007208-50-0134

A1-J2displays

24 Pinone sided 2574 09-01-7241 18 - 20

22 - 2624782578

08-52-007208-50-0134

A1-J3displays

17 Pinone sided 2574 09-01-7171 18 - 20

22 - 2624782578

08-52-007208-50-0134

A1-J4*/A3-J1CPU/Driver PCB

48 Pintwo sided 4338 09-50-6245 18 - 20

22 - 2643664573

08-03-030408-03-0306

A1-J5*Switch Matrix

10 Pinone sided 2574 09-01-7101 18 - 20

22 - 2624782578

08-52-007208-50-0134

A1-J6*Switch Matrix

19 Pinone sided 2574 09-01-7191 18 - 20

22 - 2624782578

08-52-007208-50-0134

* Connectors that often need to be replaced.

There is a double sided A1-J4/A3-J1 connector, that goes from the CPU board to the driver board. The plastic housing is Molex series 4338. The 48 pin (24 per side) part number is Molex part number 09-50-6245 (with mounting flange). If you use a high-powered magnifying glass you can read the part number stamped into the rear of the housing along one edge. The housing accepts series 4366 terminals pins (or 4573 series). Gottlieb uses just the 4366 series of pins (designed for 18-20 guage) for all wires, regardless of the wire gauge (18 gauge is used in high stress applications, and 22 gauge is used in switch and lamp applications).

Regarding the single sided plastic housings, Molex sells both "with flange" and "without flange" versions. The "with flange" version is what to buy, as the "without flange" versions are special order only. But either style will work. The flange is basically some surrounding plastics allowing the connector to be bolted to a circuit board.

All other single sided connectors (except A1-J1) should ideally be replaced in their entirety. The single edge connectors can be replaced with the Molex 2574 series

crimp-on plastic housing, using 2478 (or 2578) pins (depending on the wire guage). Unfortunately these plastic connector housings are very hard to find. But the good news is we can use the current IDC plastic housing with the 2478 crimp-on pins.

Connector Parts Typically Needed (order this stuff!)On many System 80 games, these are the parts typically need (applies largely to Black Hole/Haunted House era games). That is, these are the parts needed to fix the CPU board's J1, J5, J6 connectors, and the CPU/Driver boards' A1-J4/A3-J1. Remember, the plastic connector housings on the CPU board at J1 and J4 can be reused (but any others need to be replaced, because they will be converted from IDC to crimp-on pins). Quantities are typical for doing one game.

(35) Molex 08-52-0072 crimp-on pins (for single sided connectors). (100) Molex 08-03-0304 crimp-on pins (for double sided connectors). (1) Molex 09-01-7101 plastic connector housing, 10 pins (J5), optional. (1) Molex 09-01-7191 plastic connector housing, 19 pins (J6), optional.

The single sided connector pins 08-52-0072 are available from digikey.com, part number WM2302-ND. The double sided connector pins 08-03-0304 are available from avnetmarshall.com using the Molex part number. Both of the above pins are also available from ttiinc.com (800-225-5884) using Molex part number. Note both TTI and Avnet have 500 part minimums (Digikey will sell smaller quantities). The plastic connector housings I do not have a source, but the current IDC housings can be used with the crimp-on pins.

If doing all the connectors on the CPU board, the following parts will also be needed (parts needed to do the display connectors A1-J2, A1-J3 on the right side of the CPU board):

(45) Molex 08-52-0072 crimp-on pins (for single sided connectors). (1) Molex 09-01-7171 plastic connector housing, 17 pins (J3), optional. (1) Molex 09-01-7241 plastic connector housing, 24 pins (J2), optional.

If doing the connectors on the Driver board (in addition to the already mentioned A3-J1 connector), here are those parts typically needed. This will replace the solenoid drive connectors A3-J4, J5, J6. The solenoid drive connectors are the ones the cause the most game problems when they fail (note connector J5 also handles some sound). The remaining driver board connectors (J2, J3) are lamp and sound connectors, and rarely need replaced (though connector J3 does also handle some relays, including the game over, tilt and coin lockout relays). The good news about A3-J3 is it's a double sided, 50 pin, crimp-on style connector. So its plastic housing can be easily reused, and just the pins replaced with Molex 08-03-0304 pins.

(30) Molex 08-52-0072 crimp-on pins (for single sided connectors). (100) Molex 08-03-0304 crimp-on pins (for double sided connectors). (1) Molex 09-01-7101 plastic connector housing, 10 pins (J2), optional. (1) Molex 09-01-7151 plastic connector housing, 15 pins (J4), optional. (1) Molex 09-01-7081 plastic connector housing, 8 pins (J5), optional. (1) Molex 09-01-6041 plastic connector housing, 4 pins (J6), optional.

The Connector between the CPU and Driver board.This double sided connector often has corroded pins because the CPU side of the connector is near the battery. If the double sided connector pins can not be found easily to repair the original connector, a new replacement can be purchased from Docent Electronics (937-253-2763) for $25. Docent also added the additional ground and +5 wires to this connector, as described in the previous Grounding Modification section above.

Crimp-On Connector Pin Instructions.The following documents were drawn by Bob Ellingson. It explains the removal of old connector pins, and crimping on new ones.

To install new connector pins from the strip molex pins #2478, note these diagrams.

The best way to attach the new pins is with a Molex WHT-1921 or Amp 725 crimping tool (but Radio Shack also sells a decent crimping tool). Done properly, a good tight crimping connection is better than a soldered connection (and takes a lot less time!). The crimp is done in two steps. First crimp the bare wire end in the first saddle (the saddle closest to the wiper). Second, crimp the insulation in the second saddle.

To reassemble the connector, just push the new pins into the back of the old plastic housing, until the latch "clicks". Make sure to install the pin with the wiper towards the inside!

Re-using the Current IDC Connector Housings with Crimp-On Pins.YES the IDC plastic connector housing can be re-used with crimp-on pins. The hardest part about doing this is removing the old IDC pins from the plastic housing. What follows are the steps to do this. Just do one pin at a time, so the wires/pins can not easily be mixed up.

Step One.Acquire the tools needed for this. This includes a smaller jewelers screwdriver, needle nose pliers, and a crimper.

Step Two.Using a small jeweler's screw driver, bend the pin's notch permanently down. No need to be gentle here, push it and bend it down.

Step Three.Pull the exiting wire from the IDC connector housing. If lucky, the IDC pin should come out with the wire. If not, use a pair of needle nose pliers to pull the IDC pin out of the housing. It should come out fairly easy.

Removing the IDC pin with needle nose pliers after the "notch" was bent out of the way with a jeweler's screwdriver (the blue circle

shows where the notch was bent down).

Step Four.Cut the existing wire back about a 1/4", to remove the portion of the wire that was formerly used in the IDC pin. Then crimp a new Molex 08-52-0072 pin onto the old wire (see crimping instructions above).

Getting ready to install the new crimp-on pin into the housing.

Step Five.Insert the new crimp-on pin into the housing. The crimp-on pin should fit right into the old IDC plastic housing, without resistance. If it does not go in easily, you are inserting the pin incorrectly into the plastic housing. Another possibility is the crimp-on pin may have too much material on the sides of the pin (where the pin was cut from the factory out of the reel strips), making the pin's "wings" a tad too wide. This seems to happens to about 10% of the crimp-on pins I use. To fix this, I just gently file the sides of the pin.

The new crimp-on wire and pin installed in the old IDC plastic housing.

This procedure can now be repeated for the next pin.

Removing Pins from Gottlieb Double-Side Connectors.Removing connectors pins from double sided connectors is fairly easy, if these steps are used. New replacement Molex 08-03-0304 crimp-on pins should be used.

First bend the pin inward on both sides, one at a time, using needle nose pliers.

This picture shows both pins bent inward. Don't try and do just one pin,as you will surely bend the opposite pin too.

Next insert the Molex pin removal tool between the plastic housing and the metal pin. Gently pull the wire connecting to the pin, and the pin should

pull out of the plastic housing. Next do the oppositepin, but be careful not to mix up the two pins!

Replacement EDAC Connectors.The above connectors can also be bought using the EDAC number. These connectors have solder lug (instead of crimp pins). But note that only the 10 pin connector can be purchased with the correct number of pins. For example, one can't buy a 24 pin single sided connector; instead buy a 25 pin double sided connector and use it as-is, or cut it. Though this is not a recommended way to replace connectors, here is the EDAC information:

(1) 5 pin, single sided connector (A1-J1). EDAC #307-012-500-202 (1) 24 pin, single sided connector (A1-J2). EDAC #307-050-500-202 (1) 17 pin, single sided connector (A1-J3). EDAC #306-018-500-102 (1) 24 pin (per side), 48 pins total, double sided connector (A1-J4 to A3-J1).

EDAC #307-050-500-202 (1) 10 pin, single sided connector (A1-J5). EDAC #306-010-500-102 (1) 19 pin, single sided connector (A1-J6). EDAC #306-022-500-102

Making New Connectors from Video Game Harnesses.If not buying new pins, one can make a new connector from JAMMA video game harness connector (about $15 new each). These 28 pin double sided connectors can be cut to length. I find this better than using the EDAC solder lug connectors, as the pins are replaceable. Here are the instructions for modifying a JAMMA video game harness in a system80 game:

First a IDC pin removal tool is needed. A small jeweler's screwdriver can also be used. Or take a 5 watt resistor, and cut one lead to 3/8" long (five watt resistors work nice because the resistor is like a big "handle" to grab).

Insert the 3/8" long lead of the resistor or the jeweler's screwdriver into the top (where the card edge would go) of the new JAMMA connector, between the pin and the plastic wall (see the drawings above). It's a tight fit, but it will go.

Gently pull the wire lead, and the pin should come out. Note: unfortunately this technique doesn't work on the original IDC's in many System 80 games. If it did, we could just replace the pins and not the entire connector! I haven't found a way to get the pins out of the original System 80 connectors if they are damaged.

Repeat this, removing enough wires until the connector is the size desired. Saw the end off the connector (a bandsaw works nicely for this) and save it. Saw the empty pins off and discard. On a belt sander, flatten and smooth the cut edges on the connect and the

cut off end. Super glue the end back onto the connector, making it the length desired.

Test the connector on the board before gluing to make sure the ends are trimmed to the proper length.

To make a single sided connector from a double sided one, just cut the wire from the unused side. Or remove all the unwanted pins and wires using the above removal method.

When re-soldering the connectors, use heat-shrink tubing for a good, clean look.

Circuit Board Card Edge Fingers Destroyed.When the card edge fingers on the board are destroyed and unusable, the single-sided ID connectors can be replaced with the Molex .110" header pin style connectors. This can be done by drilling 1/16" holes through the edge connector fingers on the board, and inserting the molex pins thru these hole from the non-fingered side of the board (at a right angle). Then the plastic header pin guide can be super glued to the non-finger side of the circuit board. Then on the other side of the board, the pins can be soldered to the edge connector's fingers (if possible). Note this can only be done to the single-side IDC's (there is only one double-sided IDC on the CPU board). I don't recommend this fix, but if there is no choice, it may be usable. Cleaning the existing connectors (or replacing them with the same kind) is a much better idea.

1f. Mandatory: Pop Bumper Board Fix Pop Bumper Driver Boards (PBDB) are unique to Gottlieb System80 games. They were not used on System1 games. The driver board has a limited number of driver transistors for solenoids. Using the PBDB allowed Gottlieb to increase the number of controlled coils. PBDB driven coils are good thing - a problem on System1 pop bumpers was if a pop bumper skirt was mis-adjusted, the coil could lock on and burn. The System80 PBDB does not allow this to happen because it is a "one shot" board. That is, if the switch input locks on, the PBDB will only pulse the driven coil one time, and it will not lock-on. This prevents burnt coils and other problems.

When the ball hits the skirt on the Pop Bumper, the skirt closes a switch. This switch connects to pin 4 and logic ground of a PBDB, and triggers the PBDB to momentarily ("one shot") ground the solenoid coil and fire the Pop Bumper. There is no CPU or driver board involved. There is however a second switch which closes on the pop bumper as the coil energizes. This goes back to the CPU board through the switch matrix and says "score points" (hence this second switch is for scoring points only). A similar approach was taken by Williams (but Williams had their PBDB built into the driver board itself, and unfortunately the Williams version was not "one shot").

Get the Pop Bumper Driver Board Working.Before doing any modification to a Pop Bumper Driver Board (PBDB), the best approach is to get it working. Here is a list of things to check:

First of course check the fuse. Yes every coil driven by a PBDB will have a fuse! With the game off remove the fuse and check it with a DMM. Make sure you are checking the correct fuse too (sometimes there are lots of coil fuses mounted under the playfield).

Measure the voltage at the coil. With the game on and a game started, check for 25 to 40 volts DC at *both* lugs of the coil in question. If voltage is seen at just one lug, the coil is bad.

Test the coil. With the game on and a game started, using an alligator jumper lead, connect one end to the ground strap in the bottom of the game. Momentarily touch the other end to the NON-BANDED diode lug of the coil in question. The coil should fire. If not there is no power to the coil, or the coil itself is bad.

Measure 5 volts at the PBDB. With the game on and a game started, Put a DMM on pins 5 and 6 of the PBDB (reference pin 3 is the "key" pin). Is there 4.8 to 5.2 volts DC? If not, put the black lead on the bottom panel ground strap (where all the green wires go) and the red lead on the PBDB pin 5. Is there 5 volts now? If so the ground connection to the PBDB has failed (ground comes from the CPU board connector A1J6 pin 9, check this connector - often if ground is missing to the PBDB the coil is locked-on if the coil fuse is good). The 5 volt power comes from the CPU board connector A1J6 pin 18. Check this connector too!

Test the coil-to-PBDB connection and power by jumping the PBDB pin 1 and pin 2. If the connection is good, the coil should fire. A spark may happen when you do this, and only jump these two pin momentarily or the coil may burn. If the coil does not fire, there is a wiring problem between the coil and the PBDB.

Test the PBDB itself by jumping PBDB pin 4 and pin 6. This is simulating the pop bumper skirt switch closure. If the coil fires, the PBDB is fine, and there is just a switch or wiring problem. Check the pop bumper skirt switch wiring for continuity with one wire going to PBDB pin 4 (trigger), and the other to PBDB pin 6 (logic ground).

If everything checks out so far, the PBDB itself is dead. Cracked connector header pins. This is very common. Buzz the pins with a

DMM to make sure they do not have cracked traces. The pin that seems to crack most often is the pin that connects to the metal case of transistor Q1

(pin 1). If this pin is not making contact, this can cause the pop bumper coil to lock on.

Broken traces. Because the PBDB is a single sided board, broken traces around replaced components is often seen.

Transistor Q1 (2N6057/2N6059) has failed. This is very common. Test the transistor with a DMM set to the diode function (.4 to .6 volts should be seen). A bad Q1 can cause the PBDB to not work at all, or to lock on its associated coil.

Capacitor C4 has gone open. Either or both TTL chips (74LS121 and 74LS16) have failed.

If a PBDB can not be fixed, a new one can be purchased from www.pbliz.com/id26.htm. As for fixing a broken PBDB, there are some short cuts to this procedure. For example, a kit can be purchased from Big Daddy which replaces all the parts on the board with new parts. That is certainly one approach.

But keep in mind that non-working PBDBs can be related to other things. For example, if the board is not getting 5 volts at pin 5, it just won't work! The 5 volts for the PBDB comes from the CPU board connector A1J6 pin 18, which just happens to be beneath the battery. So any battery corrosion could disable the connector fingers or the connector pins.

Likewise there are *two* different grounds supplied to the PBDB. One is the solenoid ground bus (comes in at pin 1 and goes back to the coil at pin 2). The other is the "DC ground" (pin 6, which is the logic ground). The DC Ground is again supplied by the CPU board connector A1J6 pin 9. If 5 volts is present to the PBDB, but the DC Ground is not, the pop bumpers will lock on as soon as a game is started! A bad pin or connector finger at CPU J6 is usually the culprit.

If the Pop Bumper Driver Board's fuse blows every time a game is started (and the pop bumper coil is 2.5 ohms or greater and the 1N4004 coil diode is new), suspect the two chips on the pop bumper driver board. The 74LS121 and/or the 74LS16 can have an internal short which will cause the pop bumper's 2amp slo-blo fuse to fail. This can be tested by using a DMM set to the diode function. Put the black lead on the chip's +5 volt power leg, and test each other leg with the red DMM lead. A reading of .4 to .6 should be seen for each chip leg (except for the chip ground leg).

Mandatory PBDB Upgrades.This repair is mandatory on all early System 80 games (Haunted House and before). This modification corrects a design error. Gottlieb recognized the problem, issued a technical service bulletin, and fixed this error. But many games had been sold without this fix. All pop bumper boards need to be checked to see if this factory upgrade had been made. To quickly identify this modification look for:

2 diodes (CR1 & CR2) = original (bad) design1 diode/1 jumper (CR2 & jumper) = modified/upgraded.

Left: An un-modified pop bumper driver board.Right: A modified pop bumper driver board. Note the replacement of one diode

with a jumper, and the new capacitor (installed in reverse) below it.

  Parts Needed (for each pop bumper board):

(1) 4.7 mfd 10 volt capacitor, axial or radial, for C3. (1) 47 mfd 10 volt capacitor (or even 100 or 150 or 200 mfd), for C4. (1) 1 mfd, 100 volt capacitor non-polarized (optional), for C1. (1) 10k ohm resistor 1/4 watt (optional), for R1.

Modification:

Note the negative lead position of capacitor C3. Mark the position of the negative lead with a pen right on the component side of the board (the lead towards the center of the board).

Remove capacitor C3. Insert a new 4.7 mfd capacitor in the reverse direction. That is, the

positive lead of the capacitor is now towards the center of the board (and connects to pin 10 of the 74LS121). Cross the negative mark made on the board with a pen (to make it positive) to avoid future confusion. Note there are two pads for the positive lead of the capacitor. Gottlieb did this so one can install either an axial or radial style capacitor. Just make sure to solder the unused pad so it's closed.

Note the two pads used for mounting the positive lead of capacitor C3. Gottlieb did this so one could use either style of capacitor (axial or radial). Theunused pad should be

soldered over (which hasn't been done here yet).

Remove diode CR1. Replace with a jumper wire. Remove capacitor C4 and replace this 47 mfd capacitor with a new 47 mfd

or higher (100 mfd to 200 mfd) 10 volt capacitor. Re-solder the connector header pins on the board. These solder joints often

crack from plugging and unplugging the molex connector on the board. VERY important!

Make sure Q1 is making good contact to the pcb. Remove the one screw on Q1 (the large metal cased power transistor) that has a trace connected to

it. Re-solder and tin this hole lug on the board so it makes good contact to the screw and metal case of the transistor. Re-assemble and tighten the screws.

Test the large metal Q1 power transistor (2N6057/2N6059) installed in the pop bumper driver board. Set the DMM to the "diode" setting. Then put the black lead on the bottom attachment screw of the transistor (which is connected to the metal case of the 2N6057/2N6059), and the red lead on each leg. A reading of .4 to .6 for each transistor leg should be seen. Anything else and this transistor is bad.

Pop Bumper Driver Board (PBDB) schematics and board layout. The below diagrams have been updated to reflect the mandatory and optional board changes. This includes removing diode CR1 and reversing the polarity of capacitor C3. Also thevalues for R1 and C1 have been updated.

Optional Upgrades to the Pop Bumper Driver Board.Starting with System80b, Gottlieb changed the value of two components on the pop bumper driver board. It is recommended changing these components; the pop bumpers will "pop" faster and have better action.

Capacitor C1: change to 1 mfd 100 volt non-polarized (from .01 mfd).

Resistor R1: change to 10k ohms 1/4 watt (from 1.5k ohms).

Problems that Capacitor C4 causes.The capacitor C4 on the pop bumper driver board can go open, causing the entire pop bumper board not to function or to cause the pop bumper to energize randomly and multiple times. This cap is the filter for the two TTL chips on the board. Due to the large current drain and back spike when the bumper coil energizes, this cap often fails open. Since the cap doesn't short closed, lots of people never replace it. It is best to increase the size of this capacitor from 47 mfd to 100, 150 or even 200 mfd. This will help with the filtering. Lack of filtering can cause interference from other solenoids to simultaneously activate a pop bumper solenoid.

Replacing the PBDB's 2N6057/2N6059 with a TIP102.Unfortunately the main driver transistor on the pop bumper driver board (the 2N6057/2N6059) is becoming hard to find, and very expensive. But there is good news. This transistor can be replaced with the easy to find and inexpensive TIP102. The only trick is mounting the transistor correctly to the pop bumper driver board. See the picture below for proper orientation of the TIP102. Before doing this, make sure *all* the mandatory and optional modifications have been performed to the PBDB. See the picture below for orientation of the TIP102 transistor in the PBDB. Notice the center transistor lead goes through the old 2N6057's bolt hole, and connects to the trace on the solder side of the board.

A Pop Bumper Driver Board with the 2N6057 replaced with a TIP102 transistor. This works amazingly well.

Another method of replacing the 2N6057/2N6059 transistorwith a TIP102 on the Pop Bumper Driver Board.

Adding LEDs to the Pop Bumper Driver Board (PBDB).Another nice feature that is easy to add is two LEDs. One LED shows that +5 volts is on the PBDB. This LED should always be on, signifying the PBDB is ready for operation. The other LED only comes on when the PBDB is fired. This LED shows that the input trigger has been closed, and that the PBDB is actually firing the driving transistor.

To add these two LEDs, you will need the following:

(2) LEDs, any color or variety (2) 270 ohm resistors (or even 330 or 470 ohm) (1) 1N4004 diode

You will have to drill four 1/16" holes in the PBDB to accomodate the two LEDs. Also note the orientation of the FLAT side of the LED in the pictures below. For the +5 LED, the Flat LED lead goes to ground, and the round LED lead goes through the resistor to the +5 volt PBDB trace. For the Fire LED, the Flat LED lead goes to the connector pin that goes to the pop bumper coil's ground. And the round LED lead goes to the resistor and then to the banded side of a 1N4004 diode, and then to +5 volts.

The solder side of the PBDB where the two LEDs, resistors, and a 1N4004 diode are added.

The newly mounted two LEDs on the PBDB showing +5 volts and the momentary "fire".

Other Uses for Pop Bumper Driver Boards (PBDB).These boards can be used for driving toys on other games. For example, used to turning on a motor. To do this, change the value of capacitor C3 or resistor R2. The stock value for C3 of 4.7 mfd 16 volts gives a "pulse" on time. The stock value for R2 is 12k and also gives a "pulse" on time. Increasing C3 to 47 mfd changes the time to a bit longer than 1 second, or 100 mfd changes the time to about 7 seconds. Also R2 can be changed. For example, a 100 mfd C3 capacitor and a 56K

R2 resistor gives an on-time of about 7 seconds, versus a 100 mfd C3 cap and a 12K R2 resistor gives 1.5 seconds. Here is a chart of R2 and C3 values, versus pop bumper driver board "on" times: R2 Value C3 Value "ON" Time-------- -------- --------- 12K 4.7 mfd Normal (pulse) 12K 47 mfd 1 Second 12k 100 mfd 1.5 Seconds 12K 470 mfd 5 Seconds 22K 470 mfd 7 Seconds 56K 100 mfd 7 Seconds

1g. Mandatory: Pull Up Resistor Addition

CPU Board Pull Up Resistor.This fix is mandatory. On sys80 and sys80a games before Ice Fever, Gottlieb overloaded the 6502's Read/Write line (R/W) which caused many unexplicable errors. Starting with Ice Fever, Gottlieb added a pullup resistor to the watchdog monitor assembly they added on the TC1 socket. Even if you don't have the watchdog board (which is fine, you really don't need it), add a similar pullup resistor to the CPU board. Add a 3.3K resistor to the solder side of the CPU board: from TC1 pin 7 to TC1 pin 11.

Under Playfield Pull Up Resistors.This fix is mandatory. Volcano, Black Hole and Haunted House used so many solenoids Gottlieb ran out of driver transistors on the driver board. To drive the extra solenoids, Gottlieb used lamp driver transistors that in turn drove playfield-mounted power transistors (which ultimately drove the solenoids). If one of these solenoids is stuck on, either or both of these transistors failed.

There is a design error associated with this added playfield mounted power transistor. The base of each transistor needs a 4.7k ohm 1/4 watt pull up resistor going to +24 vdc (if not already installed).

Black Hole was modified with this pull up resistor during production, so some games have it and some don't. The power transistor is a PNP type and is turned "on" when the normally high base is taken to ground (low) by the the board-mounted lamp driver transistor. To make sure the power transistors never accidentally turn "on" by them selves, the base should be tied "hi" (pulled up) to +24 vdc so it can not float or drift to a "low" condition. This pull up resistor ensures that, and makes the operation of the power transistor quicker. Note some Black Hole games originally used a 10k pull up resistor; change it to 4.7k ohms.

Gottlieb used 2N5875 power transistors, mounted on small metal brackets under the playfield, for this application (or MJ2955). These 2N5875's are rated at 10 amp 60 volts. When replacing, use a 2N5879 (15 amp 60 volts) or 2N5880 (15 amp 80 volts) or 2N5883 (25amp 60 volts) or 2N5884 (25 amp 80 volts). The amp rating is more important than the voltage.

Parts Needed:

4.7k ohm 1/4 watt resistor (one for each playfield mounted power transistor).

2N5879 (or 2N5880 or 2N5883 or 2N5884) power transistor (optional). Length of wire.

Procedure:

If the playfield mounted power transistor is a 2N5875, replace with a 2N5879 or better transistor (optional but recommended).

Test the installed 2N5875 or 2N5879 or MJ2955 transistor. First, note if there is already a pull up resistor installed. This is easy to determine; if each transistor leg only has one wire soldered to it, there is no pull up resistor. If one leg has two wires soldered to it, there is a factory installed pull up resistor. Set the DMM to "diode" setting. Put the red lead on the metal case of the transistor, and put the black lead on each leg. If the transistor is installed in the game WITH a pull up resistor, a reading of .4 to .6 from each leg should be seen. If the transistor is not installed in the game or there is NO pull up resistor, a value of .4 to .6 for one leg, and

nothing for the other should be seen. The values can be from .4 to .7; anything else and the transistor is bad.

Find +24 vdc underneath the playfield. First check the fuse block; it will be the white/red/red wire (use the voltmeter to verify). Also most of the small relays have a +24 vdc (white/red/red) wire. If using the +24 vdc at the relays, make sure the power is always present at all times (check with a meter).

Solder a wire to +24 vdc and run it to each playfield mounted power transistor.

Connect a 4.7k ohm 1/4 watt resistor to the Base of each power transistor (in addition to the wire that is already connected there). Note the base of the transistors tends to be soldered to the smaller of the two wires going to the two leads of the power transistors.

Connect the other end of the resistor to the added +24 vdc wire. Use heat shrink tubing on this end of the resistor for a nice, clean look.

Remember this when installing the playfield mounted 2N5879 transistors; with the transistor front facing left, pins right, long part of transistor up, the farthest pin from you (base) is always connected to the driver board (white/red/red wire and pull up resistor). The nearest pin to you (emitter) connects to the NON-banded diode side of the coil. The case (collector) gets the green ground.

Note the newly added 24 volt wire can be fused, but it's probably unnecessary. A fast-blo 1/8 amp fuse is probably all that is needed.

From a Gottlieb Service Bulletin #10-P1181, November 1981.

Black Hole Playfield Mounted Transistors: Q1: captive hole kicker, upper playfield. Q2: ball release to shooter lane, upper playfield. Q3: ball return gate to ball lift kicker, lower playfield. Q4: captive ball hole kicker, lower playfield. Q5: ball kicker from lower playfield to upper playfield, lower playfield.

Haunted House Playfield Mounted Transistors:

Q1: right side kicker, main playfield. Q2: trap door, main playfield. Q3: 5 bank drop target reset, cellar playfield.

Volcano Playfield Mounted Transistors:

Fire pit (connected thru driver transistor L8). Ball release (connected thru driver transistor L15). Hole Kicker (connected thru driver transistor L16).

2a. Suggested: Kicker Solenoid Fuses/Switch Arc Fix On all System 80 games, the kicker solenoids (slingshots, kicking targets, etc.) need an added capacitor to prevent switch arcing. This includes the Haunted House lower playfield up kicker coil. These non-computer controlled kickers should also have a 3 amp slo-blo fuse added to prevent coil meltdown if their switch contacts are mis-adjusted, and the coil locks on.

On Haunted House there are six kicker solenoids that are not computer controlled, and hence need a fuse added. Two on the lower playfield, and four on the main playfield. This does not include the lower playfield "K" switch up-kicker.

An added fuse on a slingshot kicker. This style fuse holder is available from Radio Shack. Very quick and convenient to install.Just remove the "hot" wire from the coil (the lead that connectsto the banded side of the diode). Then solder one lead of the

fuse holder onto the coil in its place. Solder the other fuse lead to the wire(s) just removed from the coil. The switch

arc capacitor has not been added here yet.

Parts Needed: 3.3 mfd, 100 volt, polarized capacitor (one for each solenoid). Fuse holder (one for each solenoid). 3 amp slo-blo fuse (one for each kicking solenoid).

Procedure:

Add the 3.3 mfd 100 volt capacitor across each kicking solenoid. Note the positive lead connects to the banded diode side of the solenoid. On the Haunted House lower playfield up kicker coil, connect the capacitor across the K-switch contacts and not across the lower playfield up-kicker coil (see attention #1 pictured below). Note if using the Haunted House upkicker modification, this capacitor is not needed.

Add a 3 amp slo-blo fuse to "hot" (non-ground) side of all kicking rubber solenoids. On Haunted House, this includes the lower playfield "K" switch contact solenoid (there may be a factory installed fuse there). Note the ground wires are green.

This kicking target has an added fuse and a switch arc capacitor.

Note Gottlieb says to use a 5 amp slo-blo fuse for this application. I tested a 5 amp fuse, and it took over 20 seconds for it to blow when a coil was kept activated. In this time I could smell the coil starting to burn. Using a 3 amp slo-blo fuse took 3 seconds for the fuse to blow, which is more time than a kicking coil should ever be "on"!

From the Gottlieb service bulletin# 11-P0182, January 1982.

2b. Suggested: Haunted House Up Kicker Fix The vertical up kicker (V.U.K.) used on Haunted House that kicks the ball from the lower playfield back to the main playfield tends to be weak and unreliable. To correct this problem, it is advisable to install a (modified) pop bumper driver board to give good reliable action. A weak upkicker can be a major problem with Haunted House, and much less of a problem with Black Hole. On Black Hole, if the playfield mounted 2N5879 transistors were modified with the 4.7k pull up resistors (as described above), this modification is not needed. But I would highly recommend this modification for a Haunted House!

The correct coil for the Upkicker on Black Hole and Haunted House is coil number A-4893 (535 turns of 22 gauge wire). This is mis-printed in some manuals.

There are several reasons the up kicker gets weak on Haunted House. One reason is because the normally open tungsten switch will pit with use. This pitting will cause resistance, and make the up kicker coil it connects thru weaker. Also if this switch is mis-adjusted, the coil can easily lock on and burn. I've seen this switch get RED hot while trying to kick the ball to the upper playfield unsuccessfully.

Another problem is that the four ounce steel pinball lands right on top of the up kicker's coil sleeve before it is launched vertically to the main playfield. This can cause the coil sleeve to break and/or mushroom. This causes the coil plunger to have resistance, and not operate at full strength.

Installing a Pop Bumper Driver board to replace the relay driven switch (and the coil relay that drives it) will solve the first problem mentioned. The CPU board will send a pulse to the Pop Bumper Driver board, which in turns connects the solenoid to ground for the proper amount of time. Coil burns are avoided because if the ball sensing switch gets stuck, the Pop Bumper Driver board only sends one pulse to the up kicker coil.

The next two points apply to the Haunted House upkicker, regardless if the upkicker modification is done or not.

Check where the upkicker plunger hits the ball when it's resting in the upkicker lower playfield hole. To do this, turn the game off. Put the ball in the lower playfield's upkicker hole. Manually move the upkicker plunger up, and notice where it hits the ball. It should hit it dead center. If not, adjust the upkicker mounting bracket from under the playfield till it hits the center of the ball. If the plunger hits the ball off-center, the ball will bounce off the sides of the clear plastic upkicker tube, and may not make the main playfield reliably.

Always replace the upkicker coil sleeve with a new, double flanged nylon coil sleeve. The top edge of this coil sleeve can get easily damaged from the pinball hitting it. This can cause resistance for the coil plunger.

Adjust the clear plastic upkicker ball tube. This tube must be perfectly over the upkicker ball hole in the lower playfield. If it's off-center, the ball will bounce off the sides of the tube on the way up, and may not make the main playfield reliably. Also sometimes when lowering the main playfield the tube gets mis-aligned and bends out of position. Keep an eye on this tube as lowering the main playfield!

Notice the metal bracket on the lower playfield behind the upkicker ball hole. It has a half circle cut-out, and elongated screw holes for adjustment. The clear plastic upkicker ball tube should rest against this bracket in the half circle cut-out. This is done with a spring that is connected to the clear plastic upkicker ball tube.

The bracket is adjustable; if the ball is not making it to the main playfield reliably, try moving this bracket a bit. This will change the centering of the clear plastic upkicker ball tube. Also make sure the clear plastic upkicker ball tube's spring is in place with decent tension.

If one has done the above three points, and the upkicker is still not working reliably, do the following upkicker modification. This modification for Haunted House will connect the ball kicker solenoid ground lead (non-banded solenoid diode lead) to pin 1 of the pop bumper driver board. Pin 4 is connected to the normally open relay switch of the ball kicker relay coil. Pin 2 is connected to the solenoid ground. Pin 5 is connected to +5, pin 6 is connected to logic ground.

Haunted House Upgrade Parts Needed:

(1) Pop Bumper Driver Board. If an original Gottlieb board is not available, buy a new "Tom Callahan" from Pinball Resource or Pinball Lizard's upgraded pop bumper driver board from www.pbliz.com. Both have the same pinout, and are plug and play.

(1) 6 pin female .156" Molex connector housing (for the above). (5) Connector pins for above, Molex part number 08-52-0072 (same pins

used for single sided connectors, described earlier). (1) 4.7mfd 10v electrolytic capacitor. (1) Male round .093" molex pin, Molex part number 02-09-2118 (optional,

but recommended). (1) Female round .093" molex pin, Molex part number 02-09-1119

(optional, but recommended). (1) Radio Shacks' .093" pin extractor tool, part number 274-223 (optional,

but good to have). (1) Double flanged coil sleeve. (1) A-4893 Gottlieb coil (if needed).

Procedure:

Install the Gottlieb A-4893 coil with a new double flanged coil sleeve. In a pinch, use a Williams 22-550 coil, but it won't fit real well in the existing Gottlieb coil frame. Make sure there is a diode on the coil leads with the band side of the diode going to the power lead.

If not already done, modify your Gottlieb Pop Bumper Driver board as explained previously in the section titled Pop Bumper Driver Board Fix (this reverses the polarity of capacitor C3, replaces diode CR1 with a jumper wire, and replaces capacitor C4, among other things). This modification is not required if you are installing a new "Tom Callahan" or Pinball Lizard pop bumper driver board.

On the solder side of the Pop Bumper Driver board, install the 4.7mfd 10v capacitor. Solder the minus (-) leg of the cap to pin 4 of the molex connector pin (the "input" line). Solder the positive (+) leg of the cap to pin 5 (the +5 volt line). This is a very important step! Without this filter cap, the input line running from the CPU to this new Pop Bumper Driver board can pick up noise. Every time the flippers are pressed, the upkicker can fire without this cap. Here are the pin numbers in reference to the "key" pin (the missing pin that would normally be pin 3): 6   5   4   key   2   1. This capacitor is not required if installing a new "Tom Callahan" or Pinball Lizard pop bumper driver board.

The Added 4.7mfd electrolytic capacitor on the Pop Bumper Driver Board.

Install the new Pop Bumper Driver board underneath the lower playfield. Mount it next to the relay coil that drives the upkicker coil.

On the lower playfield, remove the white-orange-blue wire from the switch on the upkicker relay coil. Remove the remaining wire connected to the other lead of this switch (and that connects to the fuse for the upkicker coil). Connect these two wires together. The switch should now have no wires connected to it. This provides power to the coil.

Note the orientation of the 6 pin molex plug on the Pop Bumper Driver board. Here are the pin numbers in reference to the "key" pin (the missing pin that would normally be pin 3): 6   5   4   key   2   1. Note pin 6 is closest to the capacitor just above the power transistor.

Remove the white-black-brown wire from the lower playfield relay coil (non-banded diode side). Connect this wire to pin 4 of the Pop Bumper Driver board. This is the "trigger" wire for the PBDB. Before this modification, the driver board completed this wire to ground to energize the relay (which in turn energized the upkicker). Now the driver board will ground this wire, triggering the PBDB. Often this wire will need to be lengthened, depending on where the PBDB was mounted. Note the relay coil will now have only one lead with wires going to it.

Remove the two green ground wires connected to the lower playfield upkicker coil (non-banded diode side). These two wires must stay connected together. Splice two more 6 inch wires into these ground wires. Now the original two ground wires which are connected together, are connected to the two new wires. Connect these two new wires to pins 2 and 6 (ground) of the Pop Bumper Driver board.

Connect pin 1 of the Pop Bumper Driver board to the non-banded diode side of the upkicker coil. Note the two green wires were removed from this terminal in the previous step. This completes the path to ground for the coil, when the PBDB is triggered.

Connect pin 5 of the Pop Bumper Driver board to +5 vdc. To do this, route a wire along the wiring harness and to the bottom of the main playfield. Splice into pin 5 of an existing Pop Bumper Driver board located there. Optionally, to do this step cleanly, use the empty pin on plugs A9-P2/J2. Install male (#02-09-1118) and female (#02-09-1119) round .093" molex pins into the empty holes in plugs A9-P2 and A9-J2. This way the lower playfield can be easily unplugged and removed.

Summary of the Pop Bumper Driver board Pinout.

Pin 1: Switched Ground (goes to device being driven by the PBDB, to complete the device's circuit to ground)

Pin 2: Ground Pin 3: KEY (not used) Pin 4: Switch input (this pin gets grounded to turn the PBDB on) Pin 5: +5 volts Pin 6: Ground

For Black Hole, connect the ball kicker solenoid ground lead (non-banded solenoid diode lead) to pin 1 of the pop bumper driver board. Pin 4 is connected to the original wire coming from the main driver board that used to go to the coil. Pin 2 is connected to the solenoid ground. Pin 5 is connected to +5, pin 6 is connected to logic ground.