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F2 Help!

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GF77

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Got a Metal Black whiche behaves a lttle strange on the sync side. It's the long board version if that matters.

For some reason I have an unstable horizontal sync on my (SCART) 1084 non-S. On the upper half of the display some lines are shaky. Now if I shift the picture horizontally everything will shift except that upper portion of the screen. Put the PCB into a Blast City, no problem. Every other PCB I own doesn't have any sync issues with this monitor. Maybe putting in the missing 1K resistor on sync will help? But I doubt. Or is my monitor getting a bit rusty catching such uncommon sync behavior? Any thoughts on that?
 
Could be worth trying:

GeorgeSpinner

Post in thread 'Final Blow Taito (F2 System) Sync'

I thought I should reply to this for completeness sake, and for anyone else having sync issues with final blow or other taito boards. This solution may help with all boards. Idk.

I purchased an image adjustment pcb that goes between the Jamma edge and the Supergun.

The reason my board doesn't sync is because the image is not in the correct place on the screen. It's too far in 1 direction or the other. I believe it's too far left but I can't be sure.

This pcb allows me to adjust the placement of the image on the screen (H & V) and I have no trouble syncing my taito board anymore.

The...
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I also noticed that the 4 big caps on each corner of the ROM/ext. board are missing/ripped off. Hm, maybe that missing filtering could cause such unstable behavior on my particular monitor? Gotta replace them asap.
 
Caps have always helped stabilize sync on any board I've recapped thus far.
Arcade boards get thrashed on location, I've seen big improvements on f3, I need to do my f2 boards still.
 
Thanks, sounds promising. All four caps are connected to the general ground plane (parts side). And on the other side to another plane. Just have to find out the specs of these caps specifically for the Metal Black ROM/extra GPU board with the TC0480 chip.
 
I have some news regarding my sync problem on my 1084. I've just booted Liquid Kids on my Mister and found an interesting option called "consumer CRT sync".

If it's "on" everything looks fine. But if I switch it to "off" I get the exact same distortion as on my Metal Black PCB. Now I have to find out how to make it work because back in the day my old Metal Black didn't cause that distortion. Maybe I have to route sync from the PCB to the video pin on my 1084? Or to video and sync? Some resistor in between maybe? At least now I know that my Metal Black PCB is fine:)
 
This consumer CRT sync on the Mister is an F2 specific option. So yeah F2 has some strange quirks going.
 
OK I solved the problem. Here is the fix for all of you having the same sync issue with F2 on a 1084 non-S monitor.

PCB sync is wired to SCART pin 20 (Video). But it also has to be connected to pin 16 (RGB Blanking/Fast Switching).

Now you have to make sure that the CVBS/RGB button on the front ogf the 1084 is set to CVBS, Button set to RGB will still show a messed up sync. If you boot in RBG mode and then switch to CVBS it will NOT fix the problem. If you boot in CVBS mode (correct sync) then switch to RGB (messed up) and back to CVBS it will stay messed up.

CVBS on the 1084 MUST be set before booting up the PCB. I'm so happy right now!
 
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