Ok - will do. I think after i swap the green/yellow back I'm also going to run the board I have in this cab, back into my working JAMMA Raiden II cab to ensure the feed is coming across properly and there's nothing going on with what appears to be a slightly hacked harness and any power issues. If the feed/screen is good, I may swap out the chassis and see if that helps with the picture size. It's a bit frustrating as I just go this k7000 chassis 'new' and was hoping it would be recapped and all good to go.
I don't think there is necessarily a problem (although there may be one) with the chassis.
There is still some debugging to do. It's important to keep in mind that it's not uncommon to need adjustments when you switch a monitor from one game to another.
The curl could be an adjustment and not a monitor issue.
C38 is a polypropylene cap, and wouldn't have been replaced as part of a cap kit or monitor service. The kit KevsArcade mentioned is a special kit of replacement values for C38 to change the width on certain monitors that weren't built with width adjustments.
You did mention that you couldn't adjust the vertical height. This is an issue if the pot doesn't do anything at all. Could be a voltage issue, could be IC2 or IC3.
Do you think these symptoms could be traced to the neck board? What I've done here, is take a 19" k7000 chassis and swapped in a 10-pin 25" k7000 neck board. This has worked before (with the same donor tube) with no problem - but I appreciate all chassis/neck boards aren't the same. I could always try another neck board....
thanks!
The signals for vertical/horizontal drive don't actually go through the neckboard. These signals are generated and shaped on the chassis (horizontal circuit including IC2, HOT, Q10, vertical including IC2, IC3), and fed through the yoke connectors .
Signal from IC1 and the rest of the video processing circuit goes into the neckboard.
This is tough to troubleshoot, because it is *almost* working, and there are a lot of variables.
It may be the case that nothing is wrong, and the issues you see can be adjusted out. However, if the v-size pot actually does nothing, something seems off on the chassis.
It could be that the yoke on the donor tube is not quite right, and one chassis was less sensitive to it being slightly out of spec than the other. This will be really hard to diagnose without trying the chassis on a proper 19k7000 tube/yoke.
Assuming that the yoke is 100 percent correct for the k7000, there could be a voltage issue. I would start by ensuring that B+ is correct. If it is low (due to a resistor drifting too high out of spec) it could cause a small picture.
If B+ is correct (123v), then you can swap in a smaller value C38 for a wider picture (width always refers to the longer dimension of the monitor - so in this case up/down).
Dan