JVL Retro has no sound and front control pad not working

[Fattdirk]

I just picked up a JVL Retro and it has two issues that I'm trying to resolve. The sound is completely dead. I pulled the CPU box and the sound amp chip looked completely fried with a nice little hole burned into it. I ended up replacing it as well as the 4 electrolytic caps on the IO board and still have no sound. Also the 1000uF cap on the main board looked pretty crappy so I replaced that. I did have one improvement in the red light on the front control pad is now on but it still doesn't work and there is no calibration option for it in test mode.

Without schematics I'm unsure how this machine works to identify if the piggyback board is bad or if it is something on the main board. Any help with be appreciated.

Thanks.

[Fattdirk]

Ok well I figured out the sound. It turned out I had plugged the ribbon cable into the wrong connector on the motherboard. Turns out you plug it into the one that says 'sound'. The joystick controls still do not work so I'm still looking for advice on those.

[lilshawn]

typically the joystick board has crap spilled on it... shorting out the encoder IC on the board. you MAY be able to remove and clean the board, but i've never had more than 50% chance of it working properly.

the joy board is simply a USB device to the computer.

[Fattdirk]

typically the joystick board has crap spilled on it... shorting out the encoder IC on the board. you MAY be able to remove and clean the board, but i've never had more than 50% chance of it working properly.

the joy board is simply a USB device to the computer.

Is it a readily available chip? Just a standard usb chip?

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[lilshawn]

I don't recall. I think it's an atmel microcontroller with built in USB. been a while since i've bothered to fix a joy board. if you replaced it you'd have to program it. I think you can still buy the boards though.

peel it open and take a look... if it's nasty dirty (which it probably is since it's kinda badly designed to keep stuff like dirt and liquids out)  get yourself a toothbrush and some 99% isopropyl alcohol and give it a scrub. it may come back to life.

[Fattdirk]

I don't recall. I think it's an atmel microcontroller with built in USB. been a while since i've bothered to fix a joy board. if you replaced it you'd have to program it. I think you can still buy the boards though.

peel it open and take a look... if it's nasty dirty (which it probably is since it's kinda badly designed to keep stuff like dirt and liquids out)  get yourself a toothbrush and some 99% isopropyl alcohol and give it a scrub. it may come back to life.

Thanks. I'll try this tonight. It is completely dead so I'm thinking this might work. I assume the menu doesn't show up in test mode because the game isn't detecting it at all. Fingers crossed this fixed it.

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[Fattdirk]

I don't recall. I think it's an atmel microcontroller with built in USB. been a while since i've bothered to fix a joy board. if you replaced it you'd have to program it. I think you can still buy the boards though.

peel it open and take a look... if it's nasty dirty (which it probably is since it's kinda badly designed to keep stuff like dirt and liquids out)  get yourself a toothbrush and some 99% isopropyl alcohol and give it a scrub. it may come back to life.

Thanks. I'll try this tonight. It is completely dead so I'm thinking this might work. I assume the menu doesn't show up in test mode because the game isn't detecting it at all. Fingers crossed this fixed it.

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Houston we have a problem

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[lilshawn]

yeah that's pretty corroded... and yes, that's typical. the machine joypad isn't really designed to take drinks being spilled on them... which is why they only used them on a couple machines...then stopped using them.

I usually find some pretty gnarly crustys around the IC, but your's looks good. it looks like just the power wire had corroded itself off... it's probably still good.

at this point... you can either

-find a scrap board somewhere with the same connector and replace it.

or do what I'd do...

-just chop off the wires and solder it directly to the board.

 (but i'm crazy and can do stuff like that. your mileage may vary)

[Fattdirk]

I soldered the wires directly to the board because this is a beater anyway and it didn't work. The picture didn't show all the corrosion but it's pretty bad. Without a schematic I might try and buzz out some of the traces but I'm not sure if I even care that muce because the joypad doesn't seem to add much to the game.

[gatorjukeboxes]

Do you want to sell that board that you have there?