Recent content by dgersic

Spy Hunter upright, one volume pot seems to be bad. I have the manual / schematics, which shows the pots connected to the SSIO, but doesn't show their values or specs. Is there a known good replacement for these?

You were right. I swapped the AY-3-8910 at F7 on the SSIO, and now I've got full sounds. Thanks.

Ok, thanks. I'll try that one first.

I have new 8910s here, so that's no problem. Do you know which one plays channels 1/2/3 by any chance?

I've been reading old messages here on MCR sound problems, but before I break out the board stack again, I wanted to run this by. This game has all original boards, power supply had battery damage, but that has been repaired. I get the music from the cheap squeek board ok, on both speakers. I...

I put a logic probe on the Z80, and it's dead. The clock is running, but there's no activity at all on the Addr or Data buses. Looks like replacing that's the next step.

With the coin door connected, one of the two coin switches work, and the play meter on the door is pulsed, so at least some of the SSIO functions seem to be working.

Somewhat answering my own question, maybe. Re-reading the "MCR II Troubleshooting Guide" again, it sounds like I can rule out the Z80. I can play the game, using the "credit" button inside the game. I don't have the coin door hooked up yet. But if the coin switches work, they are read via the...

I'm not familiar with the MCR board set, but would a dead Z80 not kill the entire SSIO board? Is the SSIO's processor doing anything other than the sound effects?

I've replaced the ribbon cables, so I'm pretty sure that they're good. I'll double check them to be sure, though. Sw3 is physically located between J1 and J2 on the board. The manual says it's located at "D14". Strangely, a quick look at the SSIO schematics doesn't seem to show it. Maybe I'm...

I'm working on a Spy Hunter that boots and plays ok, except for no sound. I get music, just no sound effects. On boot, I get the "Sound Board Interface Error" message. I've read that this could be caused by the 6116 RAM on the SSIO, and wanted to test it before blindly replacing it. The game's...

Not hacked. Removed. The (new) headers are currently sitting on my workbench. The old headers are in my garbage bin. I'm staring at copper traces and cursing because I thought I had taken pictures of this before removing them and now it turns out that I didn't.

Looks like the flat side of the "D" goes to the right. Thanks.

Because there are no direct replacements, you have a bit of a challenge on your hands, but a surmountable one. If you can get the images from these, or from somebody with a working set if yours are bad, then the rest is relatively easy. Well, if you can't find a good set of originals, building...

If your ROMs are still good (unknown) despite their physical problems, it may be worthwhile to find somebody who can dump them to images for you. Then a new set could potentially be programed (aka "burned") from the images.