K7000 width cap (C38) - metal film ok?

da66en

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So I made so changes to my K7000 and as a result my width is too big. Radio Shack had some 0.1uF 250V metalized film capacitors, and I was going to put them in parallel with C38 to see if I could get it to be right size. Most places say polypropylene caps for this, but are metal film ok? Are these metalized film capacitors actually polypropylene capacitors?
 
i don't know if you can sub them out or not.

i have the C38 correct value poly cap you need for one a 25".

this is a stock value so if you want to alter it you will need some larger or smaller values to add to it

your width coil does not do anything?

Peace
Buffett
 
i don't know if you can sub them out or not.

i have the C38 correct value poly cap you need for one a 25".

this is a stock value so if you want to alter it you will need some larger or smaller values to add to it

My C38 is the correct value, still too big :(

your width coil does not do anything?

It affects the width, but not by much. It's probably 1" too big right now.
 
just wanted to see is all to be sure.

it looks like a standard 25.

what's up with your yoke wires.

what is the value on the bright orange cap.

Peace
Buffett
 
just wanted to see is all to be sure.

it looks like a standard 25.

what's up with your yoke wires.

what is the value on the bright orange cap.

That's an older picture.

Nice catch on the yoke wires - before I got a K7000 yoke the original yoke wasn't compatible so I had an ugly DIY adapter on the yoke connector so I could use a different yoke.

The bright orange cap is gone, replaced with a 0.39uv (C38). I am hoping to get some more 0.1u's PP soon to put in parallel, to see if I can shrink it that way. I got some from Radio Shack but not sure if they are polypropylene (hence the thread), but a friend thinks he has some to give me.
 
cool keep this updated with your progress for sure.

when you have see as many K7000's as i have you notice things that are out of the norm:)

Peace
Buffett
 
cool keep this updated with your progress for sure.

when you have see as many K7000's as i have you notice things that are out of the norm:)

Peace
Buffett

So, I practically doubled C38 - the screen did shrink - but barely. Any suggestions for what else to look at? I'm still like 1" too big.
 
is the H-width coil bridged with solder taking it completely out of circuit.

i would desolder it completely and clean up the area. then resolder it back in and see if it made a difference.

that is what i would try.

Peace
Buffett
 
is the H-width coil bridged with solder taking it completely out of circuit.

i would desolder it completely and clean up the area. then resolder it back in and see if it made a difference.

that is what i would try.

Peace
Buffett

I will try, but adjusting the coil does make a small difference - so it's probably OK?
 
that is good to know that it does work.

i would continue to check for solder bridges around the area.
they could look like they needed to be bridged but not be.

Peace
Buffett
 
My HV is 21KV. Wouldn't this cause my screen to be too wide? Any suggestions what I should look at to find out why HV is low?

B+ is 131/160V. This is a 25" K7000.
 
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Anyone looking for a 25K7193 may soon find this one at the bottom of the Milwaukee river.

Can horizontal size being too big be caused by too low HV? I have a techie friend who thinks so.

Does the HOT control the HV?

If the CRT is not good, could it cause HV to drag down low? Asking in case I should bug some of my local friends if I should try this chassis on a known working game and CRT.

I might ask this on a new thread to get better exposure, but: I was looking at the test points with an oscilliscope and comparing it to the K7000 manual and the waveform on the input of the gate of the HOT looked odd. Still trying to review components there to see if there's a bad part or maybe a bad HOT. When I get home I can post a picture of it, just wondering if anyone else has looked at the gate of the HOT and can tell me if they think it looks funky too.
 
My C37 was shorted. Replaced it.... and no change. Picture too wide and HV way too low (20KV).

For 25K7193 P538 boards that have both a C36 and C69, what should the value of C36 be? The schematic shows 3600 but the Wells parts list says 4700.

Anyone else have any suggestions?
 
the C36 is .0036mf

the C69 is .0061mf.

if the chassis has both screened on the chassis you will need both values.

otherwise you will continue to short C37.

Peace
Buffett
 
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the C36 is the same .0061mf

I cannot remember what the C69 value is.

if the chassis has both screened on the chassis you will need both values.

otherwise you will continue to short C37.

Peace
Buffett

C69 is 6100. C36 I don't know, because schematic and parts list have different values.
 
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