EquinoxEquinox: Subverting the : Subverting the Dominant Paradigm in Consumer Dominant Paradigm in Consumer

Electronic DesignElectronic Design

John Miles John Miles

IntroductionIntroduction- Who am I?- Who am I?

- “Beware of programmers with screwdrivers.”- “Beware of programmers with screwdrivers.”- I have a history of solving hardware - I have a history of solving hardware problems with brute force…problems with brute force…

… … and a and a pronounced pronounced tool fetishtool fetish

Evolution of Evolution of EquinoxEquinox

Meet the ICF-CD873 …Meet the ICF-CD873 …

Meet the ICF-CD873 …Meet the ICF-CD873 …

20 buttons on top surface20 buttons on top surface– Only “Snooze” is easily Only “Snooze” is easily

recognizable by touchrecognizable by touch

– Impossible to set clock or Impossible to set clock or alarm by feelalarm by feel

Blinding LCD backlightBlinding LCD backlight Annoying “Voice Plus” Annoying “Voice Plus”

featurefeature– Never miss a 3:00 AM power Never miss a 3:00 AM power

glitch again!glitch again!

So, how do we fix it?So, how do we fix it?

The ICF-CD873 is a good target for The ICF-CD873 is a good target for mockery, because it’s a perfect example of mockery, because it’s a perfect example of the “one size fits all” fallacythe “one size fits all” fallacy

Your desired features != mineYour desired features != mine– Maybe Maybe youyou want a radio with 20 buttons you want a radio with 20 buttons you

can’t seecan’t see– OK, enough about the buttons already, we get OK, enough about the buttons already, we get

the ideathe idea Let’s define Let’s define mymy feature list… feature list…

Wish List: Radio PerformanceWish List: Radio Performance

True “DC to daylight” radio coverageTrue “DC to daylight” radio coverage– Nowadays, this means at least DC-1 GHzNowadays, this means at least DC-1 GHz

» Imagine a 25-foot long radio dial…Imagine a 25-foot long radio dial…

All common modulation typesAll common modulation types» AM AM for standard AM broadcast, aircraftfor standard AM broadcast, aircraft» WBFM WBFM for standard FM broadcast, TV audiofor standard FM broadcast, TV audio» NBFMNBFM for weather, Amateur Radio repeaters, public-service for weather, Amateur Radio repeaters, public-service

bandsbands» SSB/CWSSB/CW for HF Amateur reception for HF Amateur reception

Oh, yeah… trunk-tracking scanners are hella cool. Oh, yeah… trunk-tracking scanners are hella cool. I want one of those, too.I want one of those, too.

Don’t care about CDs…Don’t care about CDs…

Wish List: Clock DisplayWish List: Clock Display

Large clock display with automatic Large clock display with automatic dimmerdimmer– I couldn’t read the Sony’s display from 3’ I couldn’t read the Sony’s display from 3’

away without glassesaway without glasses Original plan was to use 1” LEDsOriginal plan was to use 1” LEDs These gave way to Burroughs B7971 These gave way to Burroughs B7971

NixiesNixies Eventual solution: 7” LCD touchscreen Eventual solution: 7” LCD touchscreen

with rendered B7971swith rendered B7971s

– Even better solution: LASIK surgery :-PEven better solution: LASIK surgery :-P

Wish List: Features/ErgonomicsWish List: Features/Ergonomics It wouldn’t have taken much for me to be OK It wouldn’t have taken much for me to be OK

with the Sony’s feature setwith the Sony’s feature set– Front-mounted controls (or at least haptically-Front-mounted controls (or at least haptically-

correct ones)correct ones)

– Automatic time settingAutomatic time setting

– Battery backupBattery backup

– No howlingly-stupid features (“Voice Plus”)No howlingly-stupid features (“Voice Plus”)

Ability to access receiver from Ability to access receiver from anywhereanywhere

The All-Important GAF The All-Important GAF (Girlfriend Approval Factor)(Girlfriend Approval Factor)

Receiver outgrew two smaller enclosuresReceiver outgrew two smaller enclosures 4U rack-mount server chassis = bad news in the 4U rack-mount server chassis = bad news in the

bedroom, in more ways than onebedroom, in more ways than one Antenna connections, cabling also awkwardAntenna connections, cabling also awkward Ended up with dedicated client PC (Mini-ITX) in Ended up with dedicated client PC (Mini-ITX) in

receiver’s first enclosure choicereceiver’s first enclosure choice GAF/WAF isn’t just snarky sexism in action, but a GAF/WAF isn’t just snarky sexism in action, but a

valid expression of a legitimate design goal. valid expression of a legitimate design goal. A design that considers the needs and tastes of A design that considers the needs and tastes of “normal people” will LAST.“normal people” will LAST.

Technical HighlightsTechnical Highlights• Main ReceiverMain Receiver

• Quad-conversion superheterodyneQuad-conversion superheterodyne• DC-1 GHz, all-mode coverageDC-1 GHz, all-mode coverage

• Auxiliary Data Receiver (ADR)Auxiliary Data Receiver (ADR)• Single-conversion, single-frequency superheterodyneSingle-conversion, single-frequency superheterodyne• Continuously monitors King County trunked-radio system control channel at 868.175 MHzContinuously monitors King County trunked-radio system control channel at 868.175 MHz

Technical HighlightsTechnical Highlights

• Each receiver has its own Atmel Each receiver has its own Atmel ATMega128 microcontrollerATMega128 microcontroller

• 8-bit 16 MHz CPU with 128K program 8-bit 16 MHz CPU with 128K program memory, 4K RAMmemory, 4K RAM

• LotsLots of parallel and serial I/O ports, timers, of parallel and serial I/O ports, timers, ADCs…ADCs…

• Supported by free AVR-GCC C++ compilerSupported by free AVR-GCC C++ compiler• Atmel C++ code cross-compiles under Atmel C++ code cross-compiles under

MSVC for module-level testing on bench via MSVC for module-level testing on bench via parallel portsparallel ports

• Board in photo is AVR-H128 from Board in photo is AVR-H128 from www.sparkfun.com; many other vendors www.sparkfun.com; many other vendors offer similar development boardsoffer similar development boards

Technical HighlightsTechnical Highlights• Main and auxiliary receiver controllers interfaced to Via Main and auxiliary receiver controllers interfaced to Via

EPIA Mini-ITX motherboard in server chassis via RS-232EPIA Mini-ITX motherboard in server chassis via RS-232• Trunking data (talkgroup updates, etc.)Trunking data (talkgroup updates, etc.)

• Commands from server to receiver hardware on behalf of clientsCommands from server to receiver hardware on behalf of clients

• Status/signal reports from receiver to server for distribution to clientsStatus/signal reports from receiver to server for distribution to clients

• This is all low-bandwidth traffic (38.4 kbps, plain ASCII text for easy This is all low-bandwidth traffic (38.4 kbps, plain ASCII text for easy diagnostics)diagnostics)

• Audio output from main receiver demodulator assembly Audio output from main receiver demodulator assembly sent to onboard audio line-in jack for digitization and sent to onboard audio line-in jack for digitization and streamingstreaming

• Audio transmitted as 11 kHz monoAudio transmitted as 11 kHz mono• Local clients get 16-bit PCMLocal clients get 16-bit PCM• Remote clients get ADPCMRemote clients get ADPCM

Construction Example: Construction Example: Main Antenna Input AssemblyMain Antenna Input Assembly

• Receiver is built as array of interconnected Receiver is built as array of interconnected modulesmodules• Better for RF signal integrityBetter for RF signal integrity• Easy to change your mind!Easy to change your mind!• Modules can be reused as-is in future revisions of Modules can be reused as-is in future revisions of

the project, or in different projects altogetherthe project, or in different projects altogether• Expensive parts like filters and coax relays Expensive parts like filters and coax relays

scavenged from (formerly) high-end telecom / scavenged from (formerly) high-end telecom / test equipment…test equipment…

Construction Example: Construction Example: PLL Synthesized Local OscillatorPLL Synthesized Local Oscillator

- Offers tuning resolution Offers tuning resolution and coverage normally and coverage normally found in military / found in military / government receiversgovernment receivers

- This is the only This is the only professional-quality professional-quality PC board in the receiverPC board in the receiver

- More R&D time More R&D time (months) than any other (months) than any other assemblyassembly

Construction Example: Construction Example: Second Converter AssemblySecond Converter Assembly

• Good example of “dead bug” home construction techniqueGood example of “dead bug” home construction technique• Even hardcore RF tinkerers don’t realize this technique is usable beyond 1 Even hardcore RF tinkerers don’t realize this technique is usable beyond 1

GHzGHz!!

• Among the best ways to work with RF at the prototype level, but…Among the best ways to work with RF at the prototype level, but…• Testing is important, since you can’t always model or predict exact circuit Testing is important, since you can’t always model or predict exact circuit

behaviorbehavior• This is where your equipment fetish can really save the day!This is where your equipment fetish can really save the day!

More Dead-Bug Action…More Dead-Bug Action…

• Short leads on components, Short leads on components, direct connections to ground direct connections to ground plane make your circuit ugly plane make your circuit ugly

• That means ugly = good!That means ugly = good!

• Electrons have surprisingly-little Electrons have surprisingly-little regard for aesthetics…regard for aesthetics…

Design ResourcesDesign Resources EquinoxEquinox receiver project page receiver project page www.ke5fx.com/equinox/equinox.htmlwww.ke5fx.com/equinox/equinox.html

» Download the client app and give it a spinDownload the client app and give it a spin!!

John Miles, KE5FX, and Richard Hosking, VK6BRO, John Miles, KE5FX, and Richard Hosking, VK6BRO, ““A Versatile Hybrid Synthesizer,” A Versatile Hybrid Synthesizer,” QEX, QEX, Mar-Apr 2004Mar-Apr 2004

» Also available online at Also available online at www.ke5fx.com/synth.htmlwww.ke5fx.com/synth.html

Analog Devices ADIsimPLL design tool (Analog Devices ADIsimPLL design tool (www.analog.comwww.analog.com))

AVR-GCC multiplatform C++ compiler (AVR-GCC multiplatform C++ compiler (www.avrfreaks.net/AVRGCCwww.avrfreaks.net/AVRGCC//))

QEX/Communications QuarterlyQEX/Communications Quarterly((www.arrl.org/qexwww.arrl.org/qex))

Component SourcesComponent Sources• www.ebay.comwww.ebay.com

• Business & IndustrialBusiness & Industrial

• Industrial Electrical & TestIndustrial Electrical & Test• Electronic ComponentsElectronic Components• Test EquipmentTest Equipment

• AlphatronicsAlphatronics

• In Tukwila, not far from Fry’s and other attractionsIn Tukwila, not far from Fry’s and other attractions• http://shop.vetcosurplus.com/catalog/http://shop.vetcosurplus.com/catalog/

• In Bellevue, great selection of RF coax/connector hardware, much moreIn Bellevue, great selection of RF coax/connector hardware, much more• wwwwww.digikey..digikey.comcom

• Largest selection / best service / moderate pricesLargest selection / best service / moderate prices• www.minicircuits.www.minicircuits.comcom

• Personal financial Armageddon for the RF hackerPersonal financial Armageddon for the RF hacker• wwwwww.jameco..jameco.comcom

• Similar to Digi-KeySimilar to Digi-Key• www.futurlec.www.futurlec.comcom• www.sparkfun.www.sparkfun.comcom

• Good sources for microcontroller prototyping aids, other partsGood sources for microcontroller prototyping aids, other parts