Spyhunter sound problem

dyno

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I am missing some sounds on my spyhunter. The music works fine but I am only getting a few sound effects and they are very faint. I tested the volume control and it is fine and when I test the channels only channel 6 seems to be working. I changed the 8910 ic's and it didn't make a difference.
 
I am missing some sounds on my spyhunter. The music works fine but I am only getting a few sound effects and they are very faint. I tested the volume control and it is fine and when I test the channels only channel 6 seems to be working. I changed the 8910 ic's and it didn't make a difference.

There's a lot more to the audio circuits besides the two 8910's. It could be any of the support logic around the 8910's.......or, less likely, the small power amp board.

Edward
 
I'm having a similar issue with one I'm working on. I suspect mine is missing all of the digital audio. I have music, but nothing else. A friend told me that his was doing the same thing, and that it's likely the processor (Z80?) on the top board in the PCB stack (exposed to the inside of the cabinet when the stack is installed). I haven't tried swapping it out yet.

Does anyone know of some troubleshooting information for the sound in these? I found a bunch of stuff regarding the power, etc. I also found that there are two volume controls, but haven't gotten back into mine to figure out if one is just mis-adjusted. Apparently they are labeled Left and Right, but are actually music and sound. I'm sure it won't be that easy on the game I'm working on, as nothing has been easy thus far.

Thanks.
 
Following up to my own post, but here's some additional information I've found. Maybe some of it will be of assistance.

http://forums.arcade-museum.com/showthread.php?t=82387
http://forums.arcade-museum.com/showthread.php?t=101413
http://forums.arcade-museum.com/showthread.php?t=54710
http://forums.arcade-museum.com/showthread.php?t=145493 (Toward the end of page 1, continuing on page 2)
http://forums.arcade-museum.com/showthread.php?t=116714 (Refers to music, not digital audio)

Enjoy. I'll try to remember to report back after I've had a chance to work on mine a bit more.
 
Any luck?

I have a few Spy Hunter SSIO's that I have isolated to problems on the board, and not any of the socketed components.

#1- Missing Channel 2
#2- Missing Channel 3
#3- Missing Channel 6
#4- Missing all sounds, but does not give "Soundboard Interface" error.

Been working on Spy Hunter stuff for the last couple weeks so they are going on the shelf until after Christmas.

BTW: Yes, I know the posts are 4 years old.
 
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Indeed!

I spent some time today printing out the SSIO schematics large enough to read, highlighting paths, and reading the MCR-2/3 guide that Bally published.
Right now I have 7 complete, tested, ready-to-go sets of Spy Hunter PCBs. That's good for now. :)

Man, where would this hobby be without guys like Clay Cowgill. If you have access to an eprom burner, download Clay's MCR SSIO test rom. That should at least help with SSIO troubles.

http://www.multigame.com/mcr_sound.html
 
The one bit of info that I can't find explicitly is: Which 74191's correspond to each of the 6 channels? The schematics don't say, and I can't find any posts that talk about it.
It should be easy to figure out once I get back to troubleshooting. There are 2 sound gen chips that have 3 identical filtering circuits each. If 5 of the 6 on a board work, the non-working one should be pretty obvious, then just need to trace back to the failed component. Could be something as simple as the +12 isn't getting to the last amp in that particular ckt.
 
spy hunter hum

I saw this thread on testing/troubleshooting spy hunter sound issues.

My spy hunter has a terrible hum coming through both channels. You can hear the peter gunn theme, the car engine, and occasionally the scrubbing sound the car makes if you drive on the edge of the road. No machine guns, smoke screen or other vehicle sounds.

If you touch the power transistors on the power amplifier one gets burning hot, the other gets real warm.

Any suggestions on troubleshooting this?
 
Are you using the original power supply or a switching power supply? Unplug the Cheap Squeak Deluxe (the one on the left with the huge chip as you are looking in the back), and then turn it on.

Replacing the capacitors on your Dual Power Amp can't hurt and make sure the connections for the wiring from the SSIO, CSD, & DPA are clean.
 
spy hunter hum

I am using the switcher plugged into the spare outlet of the power brick. I haven't been able to get the stock power supply to work (yet). I will try the suggestions and report back. thanks.
 
report back

Ok - i unplugged cheap squeak and no effect.

I also tried the recommendation of putting a capacitor between the 12+ and the ground. No effect.

The humming on several occasions disappeared and some of the game sounds re-appeared. The sounds that re-appeared were the road sounds, vehicles crashing, and the slide sound when your car goes off the road. No weapons sounds.

On the Dual sound amp - the power transistor closest to the back door was burning hot to touch. the inboard one was warm.

Pete gunn actually came through clear without any distortion (unless the volume was cranked to max and then it was distorted real bad).
 
Switchers are known to cause hum in Spy Hunter audio; that's why I'm still using my original linear power board.

Switcher hum is annoying and it's distracting but it shouldn't be causing the issue as badly as what you're describing. So likely you have 2 issues; whatever your problem is and then moderate hum caused simply by using a switcher.

If you just want it fixed, pull your main pcb set, your dual amp board, and your linear power board and send them off to cdjump for repair and they'll come back working 100%.

Is there anyone in your area with a spy hunter game that you can swap parts into for testing?
 
HUMMMMmmmmMMmMMmm.

Switchers are known to cause hum in Spy Hunter audio; that's why I'm still using my original linear power board.

Switcher hum is annoying and it's distracting but it shouldn't be causing the issue as badly as what you're describing. So likely you have 2 issues; whatever your problem is and then moderate hum caused simply by using a switcher.

If you just want it fixed, pull your main pcb set, your dual amp board, and your linear power board and send them off to cdjump for repair and they'll come back working 100%.

Is there anyone in your area with a spy hunter game that you can swap parts into for testing?

I had to use a 10,000uf cap to get the hum to an acceptable level while using a switcher in Spy Hunter. When I unplug the CSD, the hum goes away entirely. When I put a 90412 in it, the hum also goes away. The only reason I went back to the switcher (for now) is there is a problem with my 90412 which keeps the NVRAM from saving high scores. Haven't had time to look into it and will probably just mount a cordless phone battery in the cab and tie it into the 90412.
 
humming away

The hum comes through both channels (if you look at the speakers through the back of the cabinet you can see both vibrating like crazy).

I know it's not the switcher hum - it must be something else. It's too loud. I was going to try to swap the ay chips on the ssio board to see if I could make some of the weapons sounds come back. I did try a capacitor hooked up btw 12+ and ground to avoid the hum. No reduction. Something else is wrong.

The linear supply - supposedly that was rebuilt by el dorado games but it still doesn't work. I will eventually try a bob roberts on it. I have 4 extra ps boards and will try rebuilding a couple to test this.

I am in Chihuahua Mexico so no one is really "local" to try swapping.

At least I have video and game play works. My wife just laughs and says, "You spent how much on this - just some car on a road with really bad graphics and a burned in screen mounted in a stinky cabinet?"

Uh huh. I guess that's why it's a hobby...
 
The hum comes through both channels (if you look at the speakers through the back of the cabinet you can see both vibrating like crazy).

I know it's not the switcher hum - it must be something else. It's too loud. I was going to try to swap the ay chips on the ssio board to see if I could make some of the weapons sounds come back. I did try a capacitor hooked up btw 12+ and ground to avoid the hum. No reduction. Something else is wrong.

The linear supply - supposedly that was rebuilt by el dorado games but it still doesn't work. I will eventually try a bob roberts on it. I have 4 extra ps boards and will try rebuilding a couple to test this.

I am in Chihuahua Mexico so no one is really "local" to try swapping.

At least I have video and game play works. My wife just laughs and says, "You spent how much on this - just some car on a road with really bad graphics and a burned in screen mounted in a stinky cabinet?"

Uh huh. I guess that's why it's a hobby...

Yeah, it's switcher hum AND something else. Next time don't use El Dorado for MCR stuff, send it to Chris (cdjump here) instead and you can bet your life it'll be 100% when you get it back.

Do you get the same effect from your other power boards?

> My wife just laughs and says, "You spent how much on this - just some car on a road with really bad graphics and a burned in screen mounted in a stinky cabinet?

Ha -- wait till you get it fixed, then you'll be playing an awesome game with jammin' music and having a great time with it.
 
further testing

I switched the AY-3-8910 chips - removed chip A and B, plugged chip A into socket B and chp B into socket A.

Before I did this, I heard no machine guns, no "sliding" noise when the car would spin out and crash, no smoke screen but I did hear the oil slick, the car driving, and few other sounds. After the swap, I head the machine guns, sliding noise, and smoke screen.

That suggests to me one of those chips is bad. But the hum remained on both channels. So I am going to order new chips (and other stuff from Bob). I am going to try to rebuild the linear to see if I can get rid of the hum.
 
I switched the AY-3-8910 chips - removed chip A and B, plugged chip A into socket B and chp B into socket A.

Before I did this, I heard no machine guns, no "sliding" noise when the car would spin out and crash, no smoke screen but I did hear the oil slick, the car driving, and few other sounds. After the swap, I head the machine guns, sliding noise, and smoke screen.

That suggests to me one of those chips is bad. But the hum remained on both channels. So I am going to order new chips (and other stuff from Bob). I am going to try to rebuild the linear to see if I can get rid of the hum.

Yeah, definitely sounds like the 8910s will fix your missing sounds.

You might try rebuidling the linear power board and holding off on replacing the connectors because that's supposed to be challenging. You can also get the big filter caps for the power brick from Bob at the same time. I doubt it's causing the hum but you might as well replace them since you're rebuilding power stuff.
 
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Update to this - I had tried to rebuild my linear supply and had mixed success.

Long story but I fried my switcher while trying to do some troubleshooting on the hum. Hopefully, the cpu and the cheap squeak were not also affected in that event. I have a new switcher on order.

But I did conclude that actually it was the speakers that caused the hum. So for the price of a switcher, and hopefully nothing else, I found the problem.

I am working on the linear now. Update to that post is following.
http://forums.arcade-museum.com/showthread.php?p=3065236#post3065236
 
I don't have any digital audio at all. Just music. Would 8910's be the first approach? I've already replaced all the MCR cables and recapped the Dual Audio amp.
 
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