K6100 glitches after partial rebuild

nanoryan

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Hey guys!

Trying to bring a 6100 back from the dead. This is an early P314 85X0147C model that was in a Space Duel project I picked up.

Originally, it showed just two tiny spots in the center of the screen when turned on. I purchased an Ian Kellog total rebuild kit (minus frame transistors) and replaced all the caps except the two on the raised protection PCB (because they weren't labeled and I didn't want to guess). I also replaced a significant number of resistors, diodes, and non-heatsinked transistors. I skipped the IC and adjustment pot in the HV section - wanted to wait to see if they are really needed before replacing.

The good news is that the monitor now fires up and has a nice bright picture - but it's glitching and wavy like crazy. See vid below. Any suggestions?

https://www.youtube.com/watch?v=opJ9fRBn50E

Would love to get this thing repaired and back into its Space Duel where it belongs. :)
 
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Did you not replace the 4 heatsinked transistors on the deflection board?

They are very common failure points and that wiggling can be caused by them. Though It does look like your tempest board may have some issues on its own.
 
Did you not replace the 4 heatsinked transistors on the deflection board?

They are very common failure points and that wiggling can be caused by them. Though It does look like your tempest board may have some issues on its own.

Hi Ian!

The Tempest is running OK.. I am using it as a test bench because it works fine with it's dedicated monitor.

I didn't replace the 4 heatsinked deflection transistors - I will do that next. Will any type of paste work when I re-mount the heatsinks?

Also - on the raised protection PCB, where are C1 and C2 located? On my monitor the PCB doesn't have any labels. One of the cap specs in the kit didn't match what was already on the PCB so I didn't want to chance it.
 
you can safely use any thermal compound for the transistors.

The risen protector board should use the two axial caps that were in the kit. (not the 160/200V HV cap)


You should use all the caps even if they don't match what is in your board. some cap values are upgrades to improve performance.
 
you can safely use any thermal compound for the transistors.

The risen protector board should use the two axial caps that were in the kit. (not the 160/200V HV cap)


You should use all the caps even if they don't match what is in your board. some cap values are upgrades to improve performance.

Thanks Ian!

I will track down some thermal compound and get those transistors swapped. Do you know what the IC in the HV section is responsible for? On the fence if I should replace that - I have limited success replacing ICs. :)
 
Thanks Ian!

I will track down some thermal compound and get those transistors swapped. Do you know what the IC in the HV section is responsible for? On the fence if I should replace that - I have limited success replacing ICs. :)
The IC you're referring to does sometimes go bad, but if you've got steady HV, then it is working correctly.

Further, my recommendation is to replace the two large caps on the deflection PCB (filter caps). Ian is correct regarding installing all the parts in his kit and some parts are "upgrades".

Scott C.
 
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The IC on the HV board (a 555 Timer) sets the frequency of the square wave oscillations that are fed into the transformer to induce high voltage.
 
Thanks guys! I will swap the last of the non-frame transistors and caps and hopefully that will do the trick. Will report back.
 
Thanks guys! I will swap the last of the non-frame transistors and caps and hopefully that will do the trick. Will report back.

Hopefully that does the trick. If not, post some pics and we'll collectively get it working. 😆

Scott C.
 
Hey guys, well I installed the rest of the transistors and caps in the kit (including the big filter caps) and same behavior.

One thing it does, that I wasn't able to get in the video, is that the picture will occasionally collapse into a couple bright colored dots in the center of the screen for a few seconds and then it will start displaying normally again - this has happened 2-3 times.

Any suggestions? I am stuck.
 
It's really strange how there are video glitches but it's not caused by the game PCB.

Could it be a transistor on the neck board?
 
Hey
Doubtful
The transistors on the neck board just control the colors ie the 3 x beams.

Thanks! I wonder if this might possibly be a failing flyback? I have an NOS one I can swap - just don't want to if the old one isn't suspect.
 
Hey guys!

I purchased an Ian Kellog total rebuild kit (minus frame transistors) and replaced all the caps except the two on the raised protection PCB (because they weren't labeled and I didn't want to guess).

Them 2 x caps on the Input protection raised up board are
100uF, 25V, Electrolytic. Axial x 2

I would replace them caps above

I doubt the Flyback is faulty

What value resistors are fitted in your HV Board in R901 & R907?
 
Them 2 x caps on the Input protection raised up board are
100uF, 25V, Electrolytic. Axial x 2

I would replace them caps above

I doubt the Flyback is faulty

What value resistors are fitted in your HV Board in R901 & R907?

Thanks!

I replaced both caps on the raised input protection board with 100uf 35v (part of Ian's kit). Still no change.

R901 and R907 were also replaced as part of Ian's kit. They are both now 3.9 ohm 5W.

I wasn't able to replace the below components because I couldn't find them. The monitor is an older P314 85X0147C. Anybody know if I missed any?

D812
R701
R812
R813
C922
C804
C805

Thanks again for all the suggestions! Hopefully I can get this thing going.
 
Have you reflowed all of the header pins?

Do you have a HV probe?

Yup! Reflowed all the header pins.

I don't have an HV probe but will pick one up if I need to. What would I test with it? Do you have a model you suggest? Is a special DMM required?
 
You need an HV probe to properly measure and adjust the HV, which you should do anyway, but you definitely need to do after you do any work on a vector monitor.

You want a Fluke 80k-40. They're anywhere from 50-100 bucks used on ebay, depending on how long you want to wait for a cheap one to pop up. But you can almost always get one Buy It Now for 80-90 bucks.

It works with any standard DMM. The probe is basically a huge resistive divider, and it puts out 1V for every 1000V measured. So, you just need a DMM that can measure 20-25V (or 19.5V, in the case of the 6100), as the proper value is 19.5kV.

You want to use the probe to see what your HV is doing, and if it's adjusted correctly.

Also, what version of the HV board do you have? There should be a big number on it starting with a 'P'. Later versions have an HV shutdown function, and maybe that is kicking in, if you have that version of HV board. Post the number.

-Andy
 
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