K7000 (25k7191) vertical position too high

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Hello! I have a 25k7191 with a new flyback and cap kit, but even with the VPOS cranked all the way the position is still too high. Everything else looks fine and I have confirmed the pot is still providing 25Kohms. What else can I do to bring it down?
 
Off the top of my head (please search and confirm if someone else doesn't chime in, I could be wrong) changing r81 can provide more adjustment. I don't recall if you go up or down in resistance.

Make sure it's not actually a 50/60 pot adjustment problem (check with a cross hatch pattern).Bump in the meantime.
 
Are you using a tpg or game for video signal? If it's a tpg try hooking a game up.
 
I checked the 50/60 and it's all good. The signal is coming from a Neo Geo MVS4. It appears the pot is giving the full 25k when the VPOS is as low as possible, so it would appear that increasing the resistance would be what is needed. I'll check out R81
 
I agree need to check r81, i forget whats it is suppose to be but its an odd value and people often dont have one so you will often see people "piggyback" resistors to get an acceptable value, ive done this too before i ordered the correct ones. Neo geos and capcom boards usually are not fussy about the 50/60 pots. Midways 90s boards are though.
 
I see R81 on the schematic, but I can't find it on the board for the life of me. That said, I just noticed that I think is supposed to be R83 and it looks like there is a broken leg and nothing there. Looking at the schematic I don't think this should be functioning this well if that is true. Any ideas what might be going on here (or where I can find R81)?
 

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It's clear that someone intentionally removed R83 at some point because the legs were both still there. I cleaned it up and put a 680ohm resistor on as per the schematic, but it had no effect on the VPOS and is actually causing a bit of warping in the overscan on the top, so I will likely clip it out as well. Any ideas where I can find R81 or anything else I can fix? At this point I am about to just give up.
 
Ah, I didn't have the board layout diagram. Thanks!
Good ol... old hardware. I stuck a screwdriver in VR9 to do the 50/60 adjustment and it just snapped right in half. Now I have to wait a few days for a replacement to show up.
 
Ah, I didn't have the board layout diagram. Thanks!
Good ol... old hardware. I stuck a screwdriver in VR9 to do the 50/60 adjustment and it just snapped right in half. Now I have to wait a few days for a on

Here is a picture of r81 right by heat sink mine reads 14.9ohms so its right on suppose to be 15. r100, r83 are all tied to vert pos. R83 in circuit reds around 340ohms pretty sure thats correct in circuit. R100 reads right around 270 ohms in circuit. They are all directly tied to v position

R80 is the one tied to height think its suppose to be 5.4 ohms but mine reads 3.4, you will often see it altered because it has a big impact on the amount of height adjustment you can get, think less height if you go ip in resistance more if you can down I cant remember, so in turn it can kinda screw up position as well if you cant turn it down enough to reduce the height along with the 50/60 pot will cause curving at the top of the screen and will cause it to stretch if its not set right and can also effect the position in a way a bit
 

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