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Jamma Sync adjustment PCB for non-arcade monitors (2 solutions inside)

I ordered one from Aliexpress, it arrived today.

It works great, exactly as you would expect. Two knobs, one adjusts horizontal position, the other vertical.

Only issue I experienced is it didn't display a stable picture when used in conjunction with an RGC scart cable with sync attenuation built in. Picture jumped every few seconds, as if sync were too weak. Swapped to a standard cable and no issues whatsoever.

It has a small parasite PCB on the underside, chip markings etched off. Anyone able to identify the ICs?

PART_1541397218544.jpg
PART_1541397252221.jpg
 
Bottom one looks to be a Philips device. Maybe rgb-decoder/encoder like the CXA or SAA series? I could swear i saw this on TV cards back in the 90's with composite out.
No idea about the signetics device. Could be a decoder / encoder setup. There could be some lag introduced from doing it that way but it might be too little to tell the difference. Do you notice any lag?
 
I haven't noticed any lag, have been playing Street Fighter with no difficulty.

This thing is awesome, it will be a permanent part of my supergun setup. So quick and easy to have a perfectly centred image. Especially useful as arcade boards have such a high degree of variation with sync frequencies.

I have a Bang & Olufsen CRT which shifts any RGB signal to the left, cutting off the left side of the screen. No service menu adjustment seems to rectify it. Seems to be a common problem with these sets. With this jamma image position passthrough, this problem is completly rectified.

I'd speculate there's a horizontal deflection IC, paired with a vertical deflection IC. Other than that a sync cleaner / splitter. There's a few sync deflection ICs by various companies, I may dig deeper when time permits.
 
@Frank_fjs & @RGB So could these shift circuits be implement into future supergun builds?? I think it would be a very useful added feature. But also as its own board board would be cool.

@Frank_fjs You think you will make your own version? If so, I would like to get 2 of them ;)
 
Derick2k said:
could these shift circuits be implement into future supergun builds
Click to expand...
I don't know if on-board a Supergun is the right place for this... Take my setup for example.
I use a HAS (Home Arcade System) but I also connect to a OSSC (so all my front and back porch values are adjusted digitally via menu).

This adds zero value for someone like me, and I suspect as time progresses the amount of folks using scalers will only increase.
 
jassin000 said:
Derick2k said:
could these shift circuits be implement into future supergun builds
Click to expand...
I don't know if on-board a Supergun is the right place for this... Take my setup for example.I use a HAS (Home Arcade System) but I also connect to a OSSC (so all my front and back porch values are adjusted digitally via menu).

This adds zero value for someone like me, and I suspect as time progresses the amount of folks using scalers will only increase.
Click to expand...
Yup, thats why I think as separate adapter would be best, easier to build. Just saying it could probably be integrated into future SG builds. Also I like the simplicity and speed of just turning a couple of knobs to adjust these settings.
 
I reckon you're on the money regarding the Philips. I can definitely make out the N.....

I'd love to integrate my own version of this, I'll need to research how it's done first as currently I only have a loose idea.

On the supergun would be great I think, with a switch to disable for people who don't need it. Would be a challenge fitting it all on there though.

Personally I'm finding it a very useful little device.
 
Totally doable, I ordered parts for a design I had in mind long time ago, but never got around to build and test it. Not sure if I want to implement it in my supergun, it's got no use for people who use upscalers and that's the majority as far as I've noticed.
 
Would you consider implementing it as a separate device @RGB?
 
RGB said:
Totally doable, I ordered parts for a design I had in mind long time ago, but never got around to build and test it. Not sure if I want to implement it in my supergun, it's got no use for people who use upscalers and that's the majority as far as I've noticed.
Click to expand...
I'm not happy with the quality of smart tv's and monitors i have until now, just one makes my happy (my samsung flat crt who have a nice and cristal image but the screen must be adjusted to see all image on the screen) (we know you have alot to do, but this will be a nice feature on the future release). Please sir, make it happened !
 
RGB said:
Not sure if I want to implement it in my supergun, it's got no use for people who use upscalers and that's the majority as far as I've noticed.
Click to expand...
I agree, keep it as a seperate device NOT part of the HAS Supergun itself.

If I was you... I would bring back the RECO device and add this to the design.

Sure it still would do nothing for me (as I use scalers and LCD based cabs), but in this space I'm the minority.
I think most cab users have CRT tubes, so this is a natural/beneficial place to stick it.
 
Hi guys, I've registered here because of this thread.
I enjoy arcade games, I just never heard of this forum before.

I have two Taito boards that don't sync on my crt with Supergun.

Rastan Saga
Bonze Adventure.

However..they both work on my LCD tv...obv not ideal, but better than nothing.

Rastan Saga still has interference on image on LCD, whereas Bonze Adventure is fine.

Is the device that has been linked and purchased, just to change image size? H and V.
Or..Will it sync boards..

Thank you.
 
As far as I know, it just offers H and V position adjustment.

It actually weakens the sync signal a little bit due to the attenuation introduced by one or more of the ICs.

Not sure if it will help in your situation but maybe it's worth a try? It may somewhat standardise the sync signal which may help.
 
Only seems to do horizontal position?

The one on Aliexpress does both horizontal and vertical.

Also, Aliexpress is much easier to purchase from than Taobao.
 
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