60 in 1 board with K7400, syncing issue.

Snakebee

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I seem to be having a syncing issue with a 60 in 1 board on a k7400. (Previously I had a MK3 board in the cabinet working perfectly fine.) I've tried about every pin combo I can think of (vertical, horizontal, grounded, not grounded, etc.) and I'm about at my wits end. I'm wondering if there is anything else I should try before I return the 60 in 1 and try rolling the dice again?
 

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the H. Hold adjustment is on the deflection board

I decided to finally take this from the K7500 manual to share the location of it

h hold.png
 
the H. Hold adjustment is on the deflection board

I decided to finally take this from the K7500 manual to share the location of it

View attachment 774254
Thanks for sharing this. I turned it on this morning and the image was miraculously stable without any adjustment. Not sure WTH was going on last night.

For this chassis though, what is the distinction between the two sets of sync pins at 1 and 2 and 5 and 6?
 
Thanks for sharing this. I turned it on this morning and the image was miraculously stable without any adjustment. Not sure WTH was going on last night.

For this chassis though, what is the distinction between the two sets of sync pins at 1 and 2 and 5 and 6?
5/6 is positive sync, 9/10 is negative sync

and on a K7400... they're exactly the same, so that part doesn't even matter
 
5/6 is positive sync, 9/10 is negative sync

and on a K7400... they're exactly the same, so that part doesn't even matter
According to the k7500 manual pins 9/10 are green/red while 5 is horizontal/comp and 6 vertical.

I'm guessing I'm missing something here. 🤔
 
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According to the k7500 manual pins 9/10 are green/red while 5 is horizontal/comp and 6 vertical.

I'm guessing I'm missing something here. 🤔
you are entirely wrong. read the schematics if you don't believe me that there's no sync polarity on those.
 
Am I looking at a different different k7500 manual than you?
View attachment 774387
I thought about this after the fact, I have had that pinout order memorized in my head for many years and my brain tells me I don't need to read that but I was wondering if they reversed the order somehow LOL my mistake

based on the orientation of the header, I can see how they would get that negative horizontal sync pin is pin 1. you'll observe they notate both sets of sync pins as a +/- though.

for JAMMA games pin "10" +/- Horizontal/Composite Sync is the only pin you need to connect to, but on this generation Wells-Gardner monitors pin "5" works also
 
I thought about this after the fact, I have had that pinout order memorized in my head for many years and my brain tells me I don't need to read that but I was wondering if they reversed the order somehow LOL my mistake

based on the orientation of the header, I can see how they would get that negative horizontal sync pin is pin 1. you'll observe they notate both sets of sync pins as a +/- though.

for JAMMA games pin "10" +/- Horizontal/Composite Sync is the only pin you need to connect to, but on this generation Wells-Gardner monitors pin "5" works also
Haha, that makes sense. I'm pretty inexperienced with this stuff so I just assume I've misread and/or understood things in most cases.

Another noob question: Is it possible to flip the image into the vertical position without physically rotating the monitor?

Sidenote: I realize the brightness is way up in this photo. I'm not able to adjust it down on the flyback. I'm guessing I need to replace it. =|
PXL_20241012_150607857.jpg
 
Haha, that makes sense. I'm pretty inexperienced with this stuff so I just assume I've misread and/or understood things in most cases.

Another noob question: Is it possible to flip the image into the vertical position without physically rotating the monitor?

Sidenote: I realize the brightness is way up in this photo. I'm not able to adjust it down on the flyback. I'm guessing I need to replace it. =|
View attachment 774423
short answer, no

that's not how CRTs work. and one of the common OEM flyback failures is the focus/brightness will drift on their own, I'm sure I've seen it before but I don't remember Screen not being able to adjust down.
 
short answer, no

that's not how CRTs work. and one of the common OEM flyback failures is the focus/brightness will drift on their own, I'm sure I've seen it before but I don't remember Screen not being able to adjust down.
I figured this was the case after I did some more reading. Guess I'll have to set up another cabinet where the CRT can be flipped more easily. The current set up I was going for was a 25in in a KRC cabinet. I don't think it's possible to flip this even if I wanted to.
 
I don't see any raster lines in your last picture. Have you tried turning the brightness and contrast down on the remote board? What happens when you adjust the Screen knob higher on the flyback?

I would try turning the brightness and contrast down. Don't forget about the sub contrast if this chassis has one. Then turn up the flyback.
 
I don't see any raster lines in your last picture. Have you tried turning the brightness and contrast down on the remote board? What happens when you adjust the Screen knob higher on the flyback?

I would try turning the brightness and contrast down. Don't forget about the sub contrast if this chassis has one. Then turn up the flyback.
Thanks for pointing that out. I actually haven't messed with this chassis too much, It's an extra I recently acquired. I want to say that adjusting the screen knob on the flyback did (essentially) nothing. After I realized that the image couldn't be flipped with the 60 in 1 I just threw an LCD into the cabinet. The kids were really gung-ho about playing something.
 
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