SPY HUNTER TROUBLE SHOOTING after a board install gone wrong!

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I hope CdJump is watching this..
It seems the luck of the Draw on this board set I recently repaired and had working great on the bench. A tech installed it back into its cab but failed to validate the PSU connector?(s) for the 20 pin connector :)
from the information I got back on it he had swapped the right and left edges of the connector and he said smoke came out :(
That was the short version of the story I got.
I finally got it back on my bench and after validating all of the roms found 2 that were Bad. One on the Main CPU and one on the video.
More checks revealed that the preamp lm3900 was in short with 12v on the outputs. I also replaced the main CPU
Heres a pic of the board set and my crazy bench in progress
The second pic is what I finally got after replacing the CPU and those 2 roms
I know mecha will probably make fun of my little CRT LOL
:)
.
Any guidance or suggestions on what I should look at next would be much appreciated
20250330_125119.jpg20250402_213241.jpg
 
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I have the 3 boards that cdjump fixed for me 3 years ago. I need to sell them at some point. he's awesome
 
I have the 3 boards that cdjump fixed for me 3 years ago. I need to sell them at some point. he's awesome
This is my second board set to fix and this one end up back on the bench :) I can see there is life in it still but looks bad
 
sounds more like you had one of the tantalum caps on the 12v rail short out.
 
sounds more like you had one of the tantalum caps on the 12v rail short out.
That may explain the 12v on the sound output pins when measuring shield to pin ?
 
I think the sound thing may be something entirely different but I will certainly take a poke at the caps. As stated at the beginning this board was a working set till the PSU connector got mixed up.
Is there somewhere else I can look to see why I cant get a stable image.
Thank you for any replies or suggestions
 
Update, I did not find any shorted caps and not too concerned if some are open because I am not focused on the sound part of this yet.
I am still stuck at where to go next to get the video acting right.
I am sure with my continued persistence to further understand the video logic on these boards I will eventually find the issue.
suggestions,comments or ideas are greatly appreciated.
 
sounds more like you had one of the tantalum caps on the 12v rail short out.
Ive been trying to figure out what could be wrong with the video on this board set.
I grabbed a WG K4600 CRT and this is what I got for video. I'm not 100% my horz vert are correct on the monitor but looking at this image the sprites need help I think 🤔
20250411_065437.jpg
 
I think if you run it with the SSIO disconnected it flips the image or something. I had to fight a Kickman for like a week, and that's how it came out. lol

I had to fight another Spy Hunter with some kind of graphic glitches. washing the boards in the sink and straightening the chip legs contributed to that win. I would encourage enlisting the help of cdjump unless you like your hair falling out and struggling and suffering or something.
 
sounds more like you had one of the tantalum caps on the 12v rail short out.
I think if you run it with the SSIO disconnected it flips the image or something. I had to fight a Kickman for like a week, and that's how it came out. lol
I had to fight another Spy Hunter with some kind of graphic glitches. washing the boards in the sink and straightening the chip legs contributed to that win. I would encourage enlisting the help of cdjump unless you like your hair falling out and struggling and suffering or something.
Im with ya on the hair falling out thing for sure LOL :)
Since this was working before the horrible connection mistake I am going to run through all of the eproms on the video board and validate their health. Because if you were able to see a video of this... the red and blue stripes appear when there are supposed to be sprites.
 
So, if you map out the mcr power connector, if you flip it, the 12v connects to the +5v, but, none of the grounds connect, so there shouldn't be any damage.
From the image you posted, you have issues both on the cpu, and the video pcb. My guess would be bad or misplaced background video eproms on the cpu, and bad video ram on the video pcb, or misplaced ribbon cables. If the image is upside down in your cabinet and you have dual row cables, you've probably got them offset wrong, either side to side or vertically. I'm not trying to be vague, but there's too much going on for it to be a single problem, and misconnecting the interconnects is one of the first things that people inexperienced with mcr pcbs tend to do.
 
That makes sense but one gnd must have hit somewhere because it was working great before the install
Seems I am making some progress. I went back and checked the eproms again on both boards and found one on the video gen board and 2 on the cpu board
Here is the image I have now 20250413_141557.jpg
I guess I'm looking at some sprite management issues
 
Sorry if I dont provide more detail at times, its probably because I am using my phone to post and not anywhere near the bench to look at my notes
 
Ok so I'm back in the shop and did a little touch test for ICs getting hot
And found one at 12b 74ls283 on the video gen board and now I have this image...
I think I am on the right track now hopefully I can pin point the issue
 

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Ok additional probing of 13b on vid gen pcb revealed that pins 1,4,10,13 were indeed dead. I now have sprites but have black jail bars on them. Still probing.
 
@cdjump , I have not had a chance to dive any deeper into this to resolve the black jail bars on the sprites. I can see alot of 74169's and some 74258's and looks like a 74243(2G) and 74240(3G) on the vid gen PCB.
I have checked the 74169's and they all have a pulse,but havent checked much else before I got pulled to do something else.
any suggestions on where to look for causing jailbars in the sprites ?
 
Ok, jumping back on this one. I was able resolve most all the graphic problems except one. I am seeing white as static. So when I did the self test when white was to appear only showed static. 20250513_194614.jpg
Any direction on where I need to look or suggestions would be helpful

I have used the logic probe to a point I am starting to review signals using my SA but I am not sure what I am looking when analyzing 9C on the cpu. Trying to find an input or output issue in the signals.
 
@cdjump ,What information or images can I provide to help me resolve this issue. I feel confident that its in the color ram circuitry but the probe isnt reflecting any issues. I am not sure what I need to review on the SA. I am still reviewing the MCR trouble shooting guide which has been helpful to get me this far but I am at a loss. I feel like I am chasing a rabbit :)
 
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UPDATE! I have fixed the spy hunter game play and screen.. the final issue of now white fell back on the monitor I was using which was a K4900.. I have not looked closely at it but something with the sync caused the fail for any white color to blend on the screen. I connected another monitor and I am not sure which one it was a G07 or K7000 but it worked now I am working on the sound side of it to find out why I have 12vdc on the line out for both channels.
 
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