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Slot Tech Magazine

EditorRandy Fromm

Technical WritersJames Borg, Jason Czito,Vic Fortenbach, DianaGruber, Henry Kollar, ChuckLentine, Craig Nelson,Kevin Noble, Pat Porath

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Slot Tech Magazine-EditorialPage 4-Anode? Cathode? Who Names These Things,Anyway?Page 10-Obituary for an Old FriendPage 11-Quick & Simple Repairs #102Page 16-FusesPage 22-Subscriptions

Randy Fromm

TechFest 29Mystic Lake Casino

May 2014

Enroll atslot-techs.com

Publisher-Slot Tech Magazine

Dear Friends,

I don’t often ask Slot Tech Magazine’s contributors(slot techs like YOU) to write about anything spe-

cific; I don’t give them assignments. They write aboutthe stuff that breaks the most (We don’t seem to heara peep about Konami games. Why is that? Hmm . . .).

But for this month’s issue, I asked my fellow CRTmonitor “enthusiast” and Slot Tech Magazine con-tributor James Borg if he could give us some partingwords and officially say goodbye to my old friend (andmoney-maker) the CRT monitor. To paraphrase leg-endary American folk singer Woody Guthrie, “So long,it’s been good to know you, your CRT dust is a-gettin’my lungs and I got to be driftin’ along (to LCD repair).

Goodbye old friend. Thanks for some very interestingrepairs and an outstanding body of repair knowledge.

January 2014Slot Tech Magazine

Slot Tech Feature Article

The terms “anode” and,especially, “cathode”are used quite often

in the world of electronics.The commonly used diode(rectifier) has just twoterminals; they’re calledthe cathode and the anode.

Since their invention (andstill in use today) videogames have used a“Cathode Ray Tube” as adisplay. New games useLCD monitors instead ofCRTs but there are still“cathodes” lurking aboutinside as the LCD’sbacklight is typicallygenerated by “cold cathodefluorescent lamps” orCCFLs.

In order to understand thetrue meaning of the twoterms, we need to startsmall-very small. Let’s startoff by taking a look at theatom.

The smallest part intowhich an element can bedivided is called the atom(from the Greek word atmosfor “indivisible”). The atomconsists of a nucleus andone or more orbiting

Cathode? Anode?Who Names This Stuff, Anyway?

electrons (fig.1). Theelectrons orbit in a sort of“cloud” around the nucleus.For the sake of simplicity,they are illustrated here asa simple, circular orbit. Theorbits of the electrons areknown as the “electronshells” and they are sort ofstacked in discrete layers(energy levels) as they orbitthe nucleus. You can kindof compare this to the orbitof the planets around theSun (it’s not precisely thesame). A electron has anegative charge.

The atom’s nucleus isactually made of two typesof particles. One type, theproton, has a positivecharge. It is the proton thatis responsible for thepositive charge of thenucleus. The other particlein the nucleus is called theneutron. As the nameimplies, the neutron iselectrically neutral. It hasno electrical charge at all.Neutrons do not enter intothis discussion and will notbe mentioned further.

Electrons stay in orbit dueto an attraction betweenthe positively chargedproton(s) in the nucleusand the negatively chargedelectron(s) moving in orbitaround it. This is called an

“electrostatic force.” Just asthe planets are held inorbit around the sun bylong-range force of gravity,this close-in, electrostaticforce holds the electrons inorbit around the nucleus.

1st Law of Electrostatics . . .Opposite charges attractand like charges (twocharges that are alike) repel

This simple concept is thebasis for . . . Well,EVERYTHING! The universeis held together by (amongother forces) electrostaticforces, without whicheverything would be flyingapart in an ever-expandingcosmos. The concept issimple: Opposites attract. Ifa positively-charged thingyis placed near a negativelycharged thingy, they willwill be attracted towardeach other, proportional tothe amount of charge oneach body. If two similarly-charged thingys are placednear each other, they willrepel away from each other,again, proportional to thecharge.

Figure 1

Slot Tech MagazineJanuary 2014


It is interesting (andimportant) to note that thepositive charge of a protonis precisely equal (in“strength” I suppose) to thenegative charge of anelectron but with oppositepolarity. In other words, ifwe could somehow mashthe two particles togetherinto one (we cannot) theywould completely andtotally neutralize eachother leaving no remainder.

It is the number of protonsin the nucleus thatdetermine what theelement is (fig.2.) The atomon the left has just oneproton. This is hydrogen.The atom on the right hastwo protons. This is theelement Helium. Noticethat there are the samenumber of electrons inorbit has there are protonsin the nucleus. This atom issaid to be balanced,meaning that it iselectrically balanced withan equal number ofpositively-charged protonsand negatively-chargedelectrons.

Figure 3 shows the lithiumatom. Lithium has threeprotons in the nucleus sowe need three electrons inorbit in order for this atomto be balanced. However,each electron shell islimited as to the number ofelectrons it can hold. Thismakes sense as there isless room in a smaller,closer shell than there is inan orbit that is furtheraway from the nucleus. Themaximum number of

electrons for the inner shellis just two, (the next shellout can hold eight, the next18, then 32 and so on) sothe third electron isbumped up to a orbit thatis outside the first shell.

From the Wikipedia: Theelectron shells are labeledK, L, M, N, O, P, and Q; or1, 2, 3, 4, 5, 6, and 7; goingfrom innermost shelloutwards. Electrons inouter shells have higheraverage energy and travelfarther from the nucleusthan those in inner shells.This makes them moreimportant in determininghow the atom reactschemically and behaves asa conductor, because thepull of the atom’s nucleusupon them is weaker andmore easily broken. In thisway, a given element’sreactivity is highlydependent upon itselectronic configuration.

So getting back to Lithium,we now have an electronthat’s by itself in an outerorbit (the L shell). This“loner” electron is furtheraway and less stronglybound to the nucleus and

Figure 2

Figure 3

Figure 4

Figure 5


is easily pushed out oforbit. As far as we areconcerned as electronictechnicians, there are threethings that can accomplishthis: Heat (just heating upan atom can cause itselectrons to fly out of orbit),light (we use light-operatedelectronics, AKA “opto-electronics” a lot in thecasino business) or anapplied field (such as amagnetic field or anelectrostatic field).

When this happens (whenit loses an electron) theatom is no longer balanced.It has a net positive chargebecause there are nowmore protons thanelectrons (fig.4.) We givethis unbalanced atom anew name. We now call itan ion. Further, we now callthis a “positive ion” becausethere are three protons inthe nucleus (remember, thenumber of protons in thenucleus determines thetype of element) for a +3charge but only twoelectrons for a -2 charge.The net charge is +3-2=+1.Another (more proper) termfor a positive ion is “cation”(pronounced “kat ion” not“kay shun” as you mightthink if you were followingnormal rules of Englishpronunciation). It wasdiscovered and named byfamous English physicistMichael Faraday.

From the Wikipedia: Acation (+) (/Èkæt.aj.Yn/KAT-EYE-YN ), FROM THE GREEK

WORD (katá), meaning“down,” is an ion with fewer

electrons than protons,giving it a positive charge.

Sometimes the electron inthe outer shell can ask afellow electron to join himin the outer orbit. Whenthis happens, the atom hasa net negative charge andwe now call it a “negativeion” or “anion” (again,named by Faraday). Thereare three protons for a +3charge, and four electronsfor a -4 charge. +3-4=-1.

From the Wikipedia: Ananion (“) (/Èæn.aj.Yn/an-eye-Yn ), from the Greekword (ánM), meaning “up,”is an ion with moreelectrons than protons,giving it a net negativecharge (since electrons arenegatively charged andprotons are positivelycharged).

So, by definition, we canhave “balanced atoms” withthe same number ofprotons as electrons (givingthe atom a neutral charge),we can have “cations” thathave lost an electron (givingthem a positive charge) andwe can have negativelycharged “anions” that havegained an extra electron.

Author’s Note: For thepurist who is familiar withelectronics, the followingdescription is based uponthe “conventional current”description of electriccurrent flow. Yes, Iunderstand “electron flow”but for this discussion,“conventional current” is allwe need and is, IMHO, the

easiest way to understandthis. If none of thisparagraph makes sense toyou, please don’t worryabout it. Thanks.

I think you can see wherethis is going. The “cathode”is the thingy where thecations live. It is the thingythat that emits electrons.By emitting electrons,what’s left behind is thecation. An “anode” is athingy that attractselectrons. Adding electronsto the mix creates anions.So, in a nutshell, cathodesemit electrons and anodesattract electrons. Anotherway to look at this (a moreproper definition, Isuppose) is that currentflows OUT of the cathodeand INTO the anode. Thisdefinition also satisfies thedescription of the PNjunction of a semiconductordiode where current flowsINTO the type P silicon ofthe anode, despite theseeming contradiction thatthe anode is actually madefrom positively-chargedmaterial, making it full ofcations.

Sometimes electronics ispretty weird. This two-sidedlook at the actual “chargecarriers” of electric currentflow is certainly one of themost odd things aboutunderstanding theoreticalelectronics. Fortunately, astechnicians we really don’tshiv a git about most of it.Regardless, it’s always niceto know what the termsmean as long as we’re goingto throw them around.STMSTMSTMSTMSTM


Slot Tech Obituary

Of the many articles I’ve had the pleasure of writing, articles that span far and wide, which coveralmost everything under the sun (and beyond) never have I had to put pen to paper to com-pose an obituary. It is long overdue, a sad, melancholic and even heartbreaking moment. Out

of the great respect accumulated along the passage of time, I have found it more than necessary towrite a few words of remembrance for the lost, but never forgotten, Cathode Ray Tube.

The majority will remember it well, while some will smile at the memory of once being the proudowners of a highly polished wooden box that housed a mysterious glass tube. This marvel of technol-ogy had the capacity, almost magical, to show a moving picture to its captive audience. The CRT gavepeople eyes by which to see out of their normal range of vision, even from thousands of miles away.The whole world watched and held its breath in triumph and amazement as Neil Armstrong set hisfirst footsteps on the moon. This incredible feat, this historic conquest, this one small step for manand a giant leap for mankind, was only possible to share with everybody by means of the treasuredCRT. To watch history being made right in front of everybody, in glorius black and white, was atremendous achievement. I guess, in a way, this was also a giant leap for mankind.

The CRT was conceived as a product of technology and its wonders were enjoyed for six decades.Along the years, it became better, colorful, larger and more versatile. Ironically, it was the same sort ofadvancements in technology that first brought it to life, which sadly signaled its doom. Now, itsthriving career has died.

We are assembled here today, technicians and not, to pay our final respects to our honored dead. TheCRT has made way for a new dawn, a new beginning, a new form of superior technology that doesn’tunderstand about flyback transformers. It doesn’t understand about degaussing and it doesn’tunderstand about scanning coils. To the layman, this was a foreign language but to those who know, akind of warmth glowed within at being one of the select few.

In the midst of our sorrow, wonderful memories of the CRT, will always prevail.

To the dedicated technicians who kept CRT video systems working, I raise my hat. Without them,any form of success these systems were destined to reach, would have quickly crumbled into a disap-pointing failure.

Mourned by all who cared and their faithful followers, the legacy they left behind will never witheraway, and die. We will never forget the good times they gave us, and we will never forget the chal-lenges they had thrown at us, which only sealed the tremendous bond formed between techs andCRT units. Today was never possible without yesterday, and yesterday was when the CRT ruled theEarth, just like the dinosaurs did, such a very long time ago.

They served us well, and they deserved an obituary, for which I’m grateful to Randy for giving methis opportunity.

To my almost human friend, I say, ‘Good Bye… and may your soul rest in peace…’


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Ithaca Epic 950 Printer “HEAD OPEN”Ithaca Epic 950 Printer “HEAD OPEN”Ithaca Epic 950 Printer “HEAD OPEN”Ithaca Epic 950 Printer “HEAD OPEN”Ithaca Epic 950 Printer “HEAD OPEN”Switch Not Working?Switch Not Working?Switch Not Working?Switch Not Working?Switch Not Working?

We are in the process of upgradingthe firmware on our ticket printers and on one device, it wouldn’t

indicate a “HEAD OPEN” status (printerhead open). To put the printer into “down-load mode,” part of the setup is to openthe head. For some reason, it would notshow an “open” on the LED indicator. I setthe printer off to the side to look at it laterbecause I had spares to finish the task athand. When I got back to the printer andtook it apart, it was obvious what the fail-

Quick & Simple Repairs #102By Pat Porath


ure was. I gently pulled ona two pin connector whichwas for the “head openswitch” and one of the wiresbroke right off. After thewire was repaired and theprinter put back together, Idid have my “print headopen” indication and itworked perfectly.

Bally “ProgressiveBally “ProgressiveBally “ProgressiveBally “ProgressiveBally “ProgressiveBroadcast Error”Broadcast Error”Broadcast Error”Broadcast Error”Broadcast Error”

On one of our Bally pro-gressive “Quick Hits” pro-gressive games, a “progres-sive broadcast error”wouldn’t clear. A customerwas paid for his credits hehad remaining becausenone of my quick fixesworked: Rebooting theprogressive SIB board,rebooting the game,reseating CAT-5 connec-tions on the SIB, reseatingthe brain box and checkingconnections on the SIB. Allkinds of red and greenlights were flashing on theSIB telling me that itseemed like it was commu-nicating. I also checkedconnections on thebackplane board of thegame. What the? I didn’tsee a tech standing behindme LOL, I was told to clearRAM on the SIB. How doyou do that? I couldn’tremember how at the time.Power down the board, turnDIP switch 8 ON, power upfor a few seconds, thenpower down, turn DIPswitch 8 OFF, re-applypower to the board. Nextclose up thegame...and...bingo! Progres-sive error gone, game backonline.

IGT AVP “ConfigurationIGT AVP “ConfigurationIGT AVP “ConfigurationIGT AVP “ConfigurationIGT AVP “ConfigurationVerification Required”Verification Required”Verification Required”Verification Required”Verification Required”

When the game was turnedoff and a ticket printer wasswapped out, an error mes-sage appeared on the game

screen. It read: “configura-tion verification required”which is not a very goodsign. All I did was turn offthe game and swap theprinter, what happened?

After a turn of the jackpotreset key the touch screen


calibration menu appeared.Next, a time setting ap-peared. It appeared thegame somehow lost itsconfiguration a.k.a. ma-chine options. I hadthought the game was anSBX one in which cabinetmemory would need to becleared, along with gamesoftware re-downloadedbecause it appeared it hadlost the info. I called an-other tech to check it outbecause do not even have auser name or password forthe SBX login screen.

Later on, I had inquiredabout the game because itwas back up and runningpretty fast. Only “USB Key7” was needed to ENABLEthe game. I guess it was“there” just not “turned on.”Some of the game setupand options were lost, notall.

After the game software wasset to ENABLE (and prob-ably a few other optionssuch as SAS, address 1,secured enhanced, ticketprinter enable, and such)the game was fine.

Oasis 360 Floor LogixOasis 360 Floor LogixOasis 360 Floor LogixOasis 360 Floor LogixOasis 360 Floor LogixShowing Three GamesShowing Three GamesShowing Three GamesShowing Three GamesShowing Three GamesWith ProblemsWith ProblemsWith ProblemsWith ProblemsWith Problems

On the Oasis Floor Logixmonitor, there are many,many things that can beseen and used for diagnos-tics. One of them is “serialcom down.” This shows ifthere are games that haveserial communicationsdown such as when thegame is not talking TO the

Sentinel. The failure maybe a loose interface cablecoming from the game tothe Sentinel or a looseCOM board in a game ormaybe a game com optionthat has gotten lost.

I had three games basicallyin the same area, two in thesame bank and one on thenext that were showingserial com down on FloorLogicx. When taking a lookat the games (IGT AVPG20s) everything lookedfine. From SAS settings,nice flashing red and greenLEDs on the COM boardlocated on the backplane ofthe game (flashing red andgreen indicates transmit-ting and receiving data).

The Sentinel N-Compassdiagnostics looked reallygood too. There wasn’t a redor yellow border around theLCD display, which meansthat there has been a gameCOM or Sentinel COM

failure. Under the “diagnos-tics tab” using the me-chanic card everythingshowed “connected” andOK, no communicationerrors at all. When openingand closing the main slotdoor it did display accord-ingly on the Sentinel LCDmeaning I did in fact havegame TO Sentinel COM.Otherwise the displaywould not show an OPENand CLOSED status.

For the heck of it, I turnedoff game power and discon-nected main 120 VAC in-coming power. That totallykilled the game as well askilling power to the Senti-nel. I waited about 15 sec-onds then plugged it backin. This brought power backto the Sentinel, then gamepower was turned ON. Bootup appeared to be normal.Once complete, the billacceptor lit up and alllooked fine. Floor Logix waschecked to see if the power


cycle cleared the game off the screen. ITSURE DID! Doing the same procedure onthe other two games worked too. Discon-necting and reconnecting the main powercord on the games did the trick.

There was one more game that appearedon Floor Logix with a communicationproblem but the cause was obvious. Oncein a great while, an Oasis Sentinel IIIdisplay will be “froze up” (stuck in onescreen) or the screen will be all one colorsuch as gray or green. A simple powercycle of the Sentinel fixes the problem thevast majority of the time, at least the ones Ihave run across. It worked once again withthis one too.

WMS BB1 24v ProblemWMS BB1 24v ProblemWMS BB1 24v ProblemWMS BB1 24v ProblemWMS BB1 24v Problem

A slot attendant was cleaning the reels ona WMS BB1 upright game when I wascalled over to check out the problem. I wastold the reels were cleaned and the gamewas rebooted but the game wouldn’t comeback to life. The 24v LED indicator light on

the backplane board was flickering verydimly and the ticket printer diagnosticlights were flashing weird as well (as anote, the Ithaca Epic 950 printer runs offof 24v).

On the small LCD display, a printer errorappeared along with a reel tilt error. Irebooted the game only to have the sameresults occur. Since it appeared to be apower problem, the power supply located


on the bottom right handside of the game was re-placed. The 24v indicatorlight was still dim.

Next I reseated the CPUboard, no fix there either.This time the ticket printer,bill acceptor, and CPU weredisconnected. With all ofthese devices disconnectedand power turned on and ifI had my 24v, one of theunits would be causing apower problem. In otherwords, if the items are outof the circuitry and theproblem goes away withapplied power, one of theunits is causing the failure.

Even with the units discon-nected, I STILL had a powerissue. What the . . .?

Next, the reels were takenout and the power cable tothe reel control board (lo-cated under reels) wasdisconnected. No luckthere either.

I didn’t really know whichdirection to head in nextfor troubleshooting so I hadto make a phone call. I wastold there was a very goodchance the 24v power sup-ply located behind the reelshad failed. Unit behind thereels? I thought perhapsthat the unit had some-thing to do with the gamesounds. Both a co-workerand I had never heard ofthat power supply failingbefore.

So, the power supply wasrebuilt then reinstalled intothe game. As soon as game

power was turned on, the24v indicator lighted upperfectly. It wasn’t dim atall. Something to keep inmind, if a BB1 is actingunusual AND has a dimvoltage indicator LED onthe backplane board, it maybe a weak power supplybehind the reels.

- Pat Porath - Pat Porath - Pat Porath - Pat Porath - Pat [email protected]@[email protected]@[email protected]

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This article is aboutFuses. Those sweetlittle creatures that

give their all to protectother circuits in the eventof an over current condi-tion. We will spend most ofour time on two majortypes, based on popularity.There are 1/4" x 1 1/4"size, and the smaller 5mmx 20 mm size. Both come ina variety of fashions, eitherFast Blow, or Slow-Blow,glass case or ceramic case.Toward the end, we willconsider other currentlimiting safety devices.

Fast Blow fuses are used toprotect semiconductor cir-cuits where excessive cur-rent is a major indication ofa serious problem. Exces-sive current for even a shorttime can do major damageto semiconductor circuits,so we want the fuse to reactquickly. Slow Blow fuses areused in circuits that weexpect a surge of high cur-rent for a short period. Withinductive devices (such assolenoids and motors) andfluorescent lamps, we ex-pect to draw a high currentfor a short period of timebefore settling down.

Either type of fuse willsustain a slight over-cur-rent for a certain length oftime. For fast blow fuses,this is more in the range of25% over the rated valuefor tenths of a second. Forslow blow fuses, this maybe 100% over the ratedvalue for a few seconds. Ineither design, the fuse is ametallic element that getshot as current passesthrough it, and it melts.The element is usuallysome metal with a lowmelting point. It is nor-mally a good practice toreplace a fuse with theproper type and current

FusesBy Herschel Peeler


rating. When we get aroundto bench troubleshooting,we may make exceptions tothat policy, but not on thecasino floor In a game,always replace the fusewith the proper type.

Editor’s Note:Editor’s Note:Editor’s Note:Editor’s Note:Editor’s Note: NoticeHerschel said “replace thefuse with the proper type”and not “replace the fusewith the same type thatcame out.” You are not theonly technician to work ona machine. If the technicianbefore you has used toolight of a fuse (one with alower current rating) youmay find yourself chasing aproblem that doesn’t exist.Of course, too heavy a fusecan cause damage to a hostof other components orcircuitry. Always consultthe fuse labels or placard ifyou are uncertain of thefuse rating.

There is no standard partnumbering system usedbetween the various manu-facturers. Major manufac-turers each have their ownpart numbering system,even though the fuse itselfmay be identical. The“Standardized Parts List”available from the Bench

Tech forum (Delphi forums)contains a cross referenceto find equivalent partnumbers and a descriptionof the part. The older“American” standard part iscylindrical, and 1/4" indiameter, 1 1/4" long, withmetal caps on each end.The body may be glass, orceramic. Glass is cheaperand allows you to visuallyinspect the fuse. Ceramicbodies are used for highertemperature environments,usually. The more modernbody style is also cylindricalshape also, but is physi-cally smaller, 5mm x 20mm, and also comes inglass or ceramic bodystyles. This style has theadvantage of taking up lessboard space, and morepopular acceptance world-wide. There is no otherengineering advantage ofone over the other.

Fast blow fuses normallyhave a simpler internalstructure than slow blowfuses. Slow-blow fuses aremore complicated insideand look like springs. Theobjective is to have a way ofdissipating the heat for afew seconds before blow-ing.

Fuse ForensicsFuse ForensicsFuse ForensicsFuse ForensicsFuse Forensics

Problems ingames that causeexcessive currentmay be extremeor marginal. Inextreme cases,like a shortedcapacitor or apinched wire, theover-current isexcessive. You cansee that the fuse

has literally exploded. Lookfor something major to bewrong. If the fuse is onlyopen in a small point in themiddle of the fuse, andsagged before finally blow-ing out, the problem maynot be so obvious. In thesecases, the over-current wasmarginal for an extendedperiod of time.

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Fuses are not the onlyoption for over-currentproblems. Circuit breakershave an advantage in thatthey can be reset. Thedisadvantage is that theyare more equal in operationto slow blow fuses. It takesa while for the thermaloperation of a circuitbreaker to react. This isoften too long for the pro-tection of semiconductordevices. Games that usecircuit breakers will alsohave a separate fuse in thepower supply that feedspower to the logic board.

Poly fuses work much like a

Fuses look like this too!


self-resetting circuit breaker. These won-derful little devices look like capacitors andact like a slow blow fuse. Many I/O boardshave gone to using these to protect indi-

vidual components. Many have a poly fuseon each output line. IGT, to mention one,has done this. The advantage is that prob-lems in one circuit will spread no furtherthan that circuit. Polymeric fuses come indifferent packages. The PFSM is popularon IGT’s small I/Cards.

Surface Mount DevicesSurface Mount DevicesSurface Mount DevicesSurface Mount DevicesSurface Mount Devices

As does just about everything these days,fuses also come in surface mount pack-ages. Like everything surface mount, it’shard to tell one part from another. Thecases vary in structure from “big enough torecognize as a fuse” to “just another smallflat rectangle.” The smaller ones are usu-ally white, which makes them easier torecognize. The lettering may, or may not,


indicate the current rating.The biggest problem withthe small ones is that whenthey go bad, it destroys thewriting on the fuse and youcan’t tell what amp rating itwas. To makes this reallyinteresting, some people,like IGT, may use a smallvalue resistor (10 ohms) onthe board as a fuse. Thewisdom is simple. Resistorscost a penny. Fuses cost adollar. The function is thesame. When enough cur-rent passes through theresistor to exceed the watt-age rating of the resistor, itburns up.

Troubleshooting BoardsTroubleshooting BoardsTroubleshooting BoardsTroubleshooting BoardsTroubleshooting BoardsWith “Bad Fuse” Prob-With “Bad Fuse” Prob-With “Bad Fuse” Prob-With “Bad Fuse” Prob-With “Bad Fuse” Prob-lemslemslemslemslems

As mentioned earlier, al-ways replace a fuse withone of the same type, un-less... Well, here’s the ex-ception. Given the exampleof a bad Door I/O card onan IGT 960series game. The“fuse” (a 10 ohm surfacemount resistor) has goneup in smoke. Suspectedproblem is a shorted cap orsmoked IC. No visual dam-age other than the “fuse” isobvious. The fuse has doneits job and given up itsexistence to protect theboard. The obvious thing isto throw the board awayand buy another. BUT NO!!!We have to be techniciansand fix this puppy. Wereplace the “fuse” with asmall piece of wire andapply power again, keepingour finger on the powerswitch. Not having thesafety net of the fuse, theshorted capacitor now over-heats, turns brown, andgets real hot. We quickly

Fuses come in ceramic as well as glass. No,it’s not just to make your life more difficult.These arehighcurrent, highvoltage, “nonex-plosive” types.

turn power offand replacethe bad capaci-tor and thefuse. For $0.10worth of partsand ten min-utes of work,we repaired a$100 board. Ithink that isworth it. Aswith any“break therules” remedy,we stand the chance of doing damage to the board. Suchextreme current required to smoke a bad cap or IC candestroy the circuit board as well. Tiny traces that makeup the circuit are easily destroyed. But the board is al-ready considered bad and is written off. We are talkingabout ten minutes of time and a few pennies worth ofparts in an attempt to avoid a $100 loss. I have about a90% success rate finding bad caps with this method.

- Herschel Peeler - Herschel Peeler - Herschel Peeler - Herschel Peeler - Herschel [email protected]@[email protected]@[email protected]

Subscriptions & Back IssuesWhy back issues of Slot Tech Magazine areWhy back issues of Slot Tech Magazine areWhy back issues of Slot Tech Magazine areWhy back issues of Slot Tech Magazine areWhy back issues of Slot Tech Magazine areimportant to own . . .important to own . . .important to own . . .important to own . . .important to own . . .

Slot Tech Magazine is strictly technical. As such, the magazine's contents are not timecritical. The repair information and technical data contained in past issues is just as valid

today as it was the day it was published.

Additionally, current and future articles more-or-less assume that readers are already familiarwith what has been covered in past issues. This editorial policy assures that Slot TechMagazine's contributing writers are not limited to "writing down" to the level of a novicetechnician but are free to continue to produce the most comprehensive technical articles inthe gaming industry.

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