Jail bars before and after capkit - see photo

Steverd

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Just finished a capkit on my Super Hang-on because of jail bars on one side of the screen.
To my disappointment they are still there (see photo).
This is a WG7900, what else can cause this? What should I test next?



Thank you!
 
did you replace all the caps including the filter cap.

check your work to see if you got one in reverse.

did you replace the fly.

where did you get the kit from.

can you check the tube with a tube tester.

do the bars move when you adjust the width coil.

you may have a bad cap in the kit lets hope not. as it takes a different meeter to test esr and uf values.

Peace
Buffett
 
It was a Bob Roberts cap kit. So it doesn't replace 100% caps. I also tested every cap on my ESR meter before placing to be sure they are good.
Which cap is the filter cap?
 
Just finished a capkit on my Super Hang-on because of jail bars on one side of the screen.
To my disappointment they are still there (see photo).
This is a WG7900, what else can cause this? What should I test next?

Thank you!

Check the soldering of capacitor C57.
 
the filter cap is the biggest cap on the chassis.

i have it and any other cap you would need to complete the cap kit in stock.

if you want them PM me a list of locations you still need.

Peace
Buffett
 
UPDATE:

Rechecked C57 and it has proper solder, also checked for continuity around it.

As for the large Cap it's C55 labelled as 560uf 200v

My ESR meter reads it as 625uf and 0.10ESR I have a spare that measures 524uf and 0.06 ESR, would that one be better?
 
I've switched the big cap (filter cap?)
checked and doubled checked for bad solder joints, and for continuity between
anything that look even slightly different. Hooked back up and still the same.

BUT, if I play around with the brightness (on the chassis and flyback) and contrast the bars do go away. See the image below.
I wanted to make sure it wasn't some type of screen burn. But I just can't bring the brightness down and fix the contrast without the bars returning. Thought now?

capkit-2.jpg

Thanks guys!
 
try this.
if you center ALL the pots on the neck board and the brightness and contrast pots to their mechanical centers.

then adjust the fly till your raster lines go away get a good black level established.

then tweak the gains on the neck to get a good black level.

then adjust your contrast pot.

see what happens when you do that.

don't touch the brightness pot till the very last. you should be able to get it set without it if done rite with the contrast and gains on the neck board.

you may be over driving the guns in the tube.
also did you change the 3 bipolar caps on the chassis.
they are in the color circuit.

Peace
Buffett
 
you may be over driving the guns in the tube.
also did you change the 3 bipolar caps on the chassis.
they are in the color circuit.

Peace
Buffett

Thanks for the ideas, I will try them tomorrow.
As for the 3 bipolar caps, I did not replace them. I pulled them all, and they tested good on my ESR meter, so I put them back in. BUT I do have replacement, maybe I should go ahead and replace them!

Steve
 
good luck.

it can't hurt to change them.

remember that ESR rating and UF rating are two different measurements that caps have and one can be good and one can be bad.

i have seen that happen many times.

Peace
Buffett
 
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