Recent content by Womble

  1. tkg4 donkey kong is missing all sprites

    Likely you are missing -5v or, as was in my case, someone fed 5v up the -5v line and fried the ECL ram and buffer ICs.
  2. Atari ARII missing 12V - Manufacturing Fault?

    Here's a weird question for the ARII folk on here, had an ROTJ on the bench recently, and it came with it's original ARII (identical serial numbers). The board had logic faults that are now fixed, but the owner sent the ARII as he was getting 0V on the 12v rail and he took this to be a sign the...
  3. AVG Replacement IC - Flashing activity LED

    Does anyone know what the activity LED on the ArcadeShop AVG replacement chip actually signifies, other than "activity"? I've got a known good one (it works fine in my Star Wars board ), but on a faulty Vector board the activity light blinks on and off, once per second. I've tried to trace the...
  4. What pods do you own for the Fluke 9010a?

    The only one I’m missing for Arcadia is 8080. Managed to get mine fairly cheaply, even the 6809, was very lucky in retrospect.
  5. TL072 Op-Amps on Star Wars?

    Hi Folks, has anyone used TL072 op-amps instead of the original TL082s on a Star Wars Vector PCB? The TL072 seems to be regarded as a low-noise equivalent of the TL082. I can easily get 72s in a local electronics store but 82s would mean postage costs and they probably wouldn't arrive until...
  6. Raiden Fighters Request

    Awesome, major thanks for that!! There's probably hope for this board now I know the custom isn't rooted.
  7. Raiden Fighters Request

    Hi folks - does anyone have a working Raiden Fighters PCB and a multimeter handy? I've got one here with object issues and a shorted address line on the SRAMs. It isn't the SRAM chip itself, so either the custom IC is shorted, or this is normal and just a very strange design decision. With A0...
  8. OUTRUN monitor goes blank, except in test mode?

    Yeh I'd avoid TMM2063 SRAMs like the plague, they are very unreliable in old age. The original solder on the board looks fine. If you fit a socket don't use a machined pin one, they cause all sorts of problems on Outruns, basically the pins are too fat for the pcb holes and you get very bad...
  9. Please Delete

    Sorry wrong section - please delete if I havent found a way to delete it myself.
  10. Asteroids : everytime i turn it on something new is wrong with it.

    Caps aren’t usually a problem on these boards. Old single wipe sockets are, they have a very small contact point and the springy bit is usually weak or broken after 40 years. The best option is to replace them all with new dual wipe style. Chances are the board would be rock solid after that.
  11. Ghosts n Goblins glitch

    It’s actually normal, they all do it, both bootlegs and originals. Early stage 2 is the most common point for it to show up. it seems to be related to the number of sprites on screen and the complicated scrolling, too much going on and it messes up the timings of something. There are threads...
  12. Amplifone HV Board Calibration

    Thanks - but if I set it up correctly on my 25" tube, will the settings still be correct when it is back on it's original 19" tube? The owner can ship me the HV board for repair but not the tube, so I'll have to set up with my 25" tube and send back for him to reinstall on his 19", and he...
  13. Amplifone HV Board Calibration

    Hi Folks Does anyone know if an Amplifone HV board calibrated on a 25" tube would need re-calibrating if it was going to be used on a 19" tube? Both tubes are the Atari (Rauland) originals. E.g. if I repair and set the working voltage and cut off in my 25" Star Wars cockpit, how transferable...
  14. Q*Bert Bootleg Help

    The other missing parts are just standard logic and discrete components, plus an op-amp and the speech ROM, by the look of it. If you can find an SC-01A chip then it would be a fairly simple job for someone to clear the holes and populate that section. Many have asked if this just works, but I...
  15. Q*Bert Bootleg Help

    Bootleg Q berts usually don’t have the SC-01A sound chip on board. Back then this was an extremely expensive part so the bootleggers opted to trim the cost. You can see the unpopulated speech section on your board just inland from the edge connector. In theory that section could be populated to...
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