SOLVED 6100 monitor cap reads 13kV

Not a lot has been done to the deflection board. I installed the LV2K, there are char marks on the board from some old resistors in that circuit. I also replaced R107 and reflowed the the P connector pins. The board was awfully dirty, it looked like it had some moisture build up that captured a lot of dust. I blew air on it and then wiped with an alcohol cotton swab. I checked the fuses. I have not replaced C800-C803 or anything beyond the LV2000 and R107.

I can setup an order for those caps, are there any other problem areas I should have parts on hand for?
 
Not really. There's no real shotgun kit for these deflection boards. Most of the issues stem from broken solder joints on the headers, which then causes the whole deflection system (LV board, frame transistors, and transistors on the board) to nuke.

You can test Q603/604/703/704 in circuit. Compare the readings to the equivalent transistor in the opposite axis (i.e., Q603/703 should behave the same, and 604/704). In circuit, and testing in diode mode (the same way you test the frame transistors) you should get voltage drops to or from the base (center pin), to the other two pins in one direction, and either 0 or 1 small drop (0.3V) in the opposite direction. This small drop is due to testing in-circuit, but that's normal. As long as nothing is shorted, and you measure all the drops. you should be ok.

Also test D602 and 702 to make sure they are not shorted.

With the board out of the cab, reflow all headers, and test each header pin, from the tip of each pin (on the parts side) to a spot on the respective trace on the solder side, to make sure there are no cracked traces.

Beyond that, you do need to replace C800-803. Those might be the issue, if the SK is going dim. I use these ceramic ones now, which are much better and smaller than electrolytics:


If you don't have any, get yourself a dozen each of MPSA-06 and MPSA-56, as they are used on these and other boards, and are handy subs for a lot of things. Don't replace any yet, but you might need to later, so just make sure you have spares.

I'm suspecting after you replace the caps, that might solve the problem. There's no other need to shotgun anything else, except any browned resistors. Especially check R707 and 607, as they are sometimes burned, but hard to see under the bigger power resistors.
 
Also, you said you replaced R107? That should have been removed, if there's an LV2K board installed.

(The whole LV section in that corner should have been removed.)

Also, feel free to fully wash the board. You can wash all vector monitor boards (HV, deflection, and power). Spray down in the sink with any spray cleaner (Krud Kutter works by far the best, but any others will do). Take a small paintbrush to get into all the crevices. Then rinse with HOT water, and stick in front of a fan overnight to dry. They come out great. And clean boards are much nicer to work on.
 
R107 is next to the spot killer led.

I'll try washing the board, the cotton swabs only did so much. I've heard you can do it in the sink but have shied away from it so far. Thank you for all the help, I'll follow up when I have an update.
 

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Ah, you're right. I was misreading R102. My bad.

R107 gets very hot, this is normal. But they rarely fail. It feeds voltage to the heater inside the tube. It's similar to R528 on the neck, which does the same.
 
It was discolored and missing some volume. The other resistors like that are still white and look fully packed so I figured it was bad.
 
It was probably fine, as long as it tested ok.

Those are cement-filled wirewound power resistors. They are designed to take a lot of heat. Sometimes pieces can break off of them, especially when they are mechanically exposed, and they get knocked around. But as long as the filament inside isn't broken, or they aren't cracked in half, they're ok.

That particular one is sitting out on the edge of the board, so it gets a lot more dust, crap, mouse piss, and other stuff on it. It also gets VERY hot, which is why it's there on the edge, away from most other stuff. So it's often more beat up than others. But that's normal on these.
 
Alright, I replaced C800-C803. I followed all the startup procedures, checked fuses, transistors, and XY signals from the gameboard. Everything checked out. When I connected the HV (no gameboard), the spot killer turned on, then turned off. So that is an improvement and the new capacitors look like they are working. HV is correct and B+ looked good so I powered on with the gameboard. I still don't have any picture. This time, I noticed the spot killer was on and then turned off, but then it would turn on for a little while and turn off or fade off. I assume I'm still having issues with the deflection board.
 
I haven't run the other tests that were outlined above. I'll work through those and reply back when I have some results.
 
Ok, I ran all the tests and everything was checking out with my current understanding. Then I got to testing each header pin. The last header pin had a cracked trace. I had previously reflowed all the other header pins but I missed that one because there was a gap with no pin then this one at the end. I reflowed it, ran through the startup steps and finally got it started up with the gameboard and HV. I have a picture! I am so excited! Thank you so much for your help.

I'm not quite done yet. There is an issue with the drawing for white... (or after looking at it closer, it looks like the beam is turning white between moving to the next vector) It looks like white isn't turning off. I imagine that shouldn't be easier to diagnose and I'm in the homestretch. I snapped a picture before shutting it down because I didn't want to let it run too long with the white behaving like this. Any areas I should start looking at? I'm going to see if I can make any sense of the schematics and see if I can find the circuit and components for drawing white.

I'm not sure how these work, is there one beam that changes colors?
 

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Ok, I read that the ray tracing(?) retrace lines can just be an adjustment on the brightness. I turned the brightness down until the retrace lines was gone. It looks like I'm missing green as the green ship doesn't appear when I play.
 
This document shows what to check for no green. That is very handy.
 

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The colors are adjustable on the neck board. Start with turning all pots to the center positions. You should also get a can of DeOxit D5S and get some into the pots, which will clean and lube them. I spray some into a small jar, then paint it onto the pots with a small watercolor art paintbrush, to avoid making a mess if you try to spray it directly.

Then you can dial up the colorbar test screen using the game board's test mode (see the game manual), and adjust them so they are all balanced.

If one color is missing, the first thing I'd do is test the pots. You can test each one by measuring the resistance between the outer two pins. You do not have to remove them from the board. Note that the R, G, and B circuits and pots on the neck board are all the same, so you can compare measurements between them to see if anything is off.

Also, check the wiring and connectors between the game board and monitor. See the schematics for which wires are for R, G, and B, and their associated grounds.

You could also test to make sure the game board is outputting a G signal (using a probe or scope, and comparing the R and B.)

Also, test to make sure you are getting continuity for the G signal all the way to the proper pin of the neck socket. And clean the tube pins. Loss of one color is common on these when dust gets into the socket.
 
Thank you, I pulled everything out again and finally washed the boards. I centered the pots on the neck board and will hopefully find the time to assemble it tomorrow after they dry by the fan. The pots move pretty well so I'm going to avoid getting a can of DeOxit for now (I need to get better organized for storing things).

I checked the RGB from the game board and it looked good (also was not seeing green with another game board). Continuity looks similar across the outer pins of each signal. I also cleaned the tube pins. Fingers crossed for tomorrow when I wire things back up.
 
Well, I put everything back together, followed the start up procedures and all the readings checked out. I'm playing blind again. I've been looking everything over and everything seems to be working.

I pulled the neck board off and the focus pin broke off the head of the pin. I had noticed it catching on something other times I pulled it off but it seemed to be holding up ok. I had to fix the pin when I initially pulled the neck board off, it snapped at the base. I think it may be likely that I didn't solder it on quite right and I'm not getting a solid connection. When the pin snapped, the head was left inside the socket and it was to the side instead of across the connection.

I'm willing to try soldering it but it'd be nice if I could find a new one. From my initial search, it seems like a difficult part to find replacements for.
 
Yeah, that is what is going on. I pulled off the crt socket and started looking at it closer. The solder that I added doesn't allow the socket to go on all the way so I'm not getting a good connection. I found another neck board and ordered it just to replace the socket. I may try to rebuild it while waiting for the replacement but it is not an easy fix since the focus pin broke in 2 places and getting it to go deep enough to still get a snug fit... I don't know how I could get it fixed reliably without replacing.
 
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The neck sockets are no longer made, and replacements are very hard to find.

It's usually easier to just buy a new neck board. Or maybe a trashed one to salvage the socket from.

It's possible to repair the sockets. But you have to open the socket housing to do it right, and it takes some fine soldering. I have donor sockets that I'll pull individual pins from, to repair broken ones. If the focus pin is broken off and missing, for example, you can make a new one from one of the other pins. So even if you find a spare neck board, it's still worth hanging on to the dead socket, as you may be able to use it to repair another one in the future.
 
Yep, I found a neck board and it is on its way now. I didn't realize you could make a new focus pin from one of the other pins, that is good to know. I'm planning on keeping both neck boards for spare parts, especially the pins.

I did try to repair the focus pin and it sort of worked. The break is at the bottom and when I repaired it, I left too much solder at the bottom and the socket didn't fit snug anymore. That may have been a reason why I wasn't seeing green and the monitor wasn't consistently turning on.

Thank you for all the advice. i'm very excited to get the replacement neck board and get the monitor working again.
 
It worked! I had to swap a cable and clean the new neck board but after it dried, I put it on and it fits nice and tight. Wow, what a learning journey this has been. Thank you, so much for all the guidance. Now I just need to read up on how to dial in the rgb.
 
Use the RGB colorbar screen in test mode.

Look at the brightness of the thinnest R, G, and B lines, and adjust the neck pots so they are equal. When you do that, the white lines should be a nice bright white, and not tinted toward any one color.
 
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