My first rejuvenation, with unexpected results.

supertechnoboy

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I have a K7601 that originally had some major focus issues. I had previously recapped and replaced the flyback to bring the focus back to the middle of the adjustment range. It still had some focus issues with the brighter whites, so I thought the tube might be weak.

I bought a rejuvenator and adapter, and performed the rejuvenation this weekend. The tube passed all tests, but the emission was at the very bottom of the green range for all three guns. I rejuvenated all three, got some fireworks in the neck, and the emission readings rose slightly--a couple of ticks into the green.

I plugged the board back in expecting a nice bright picture, and instead got a very dim one. Same color balance, just really dark. I was able to adjust it back out, but now the focus is at the very end of the adjustment, and it looks pretty much the same as before.

1) I have not checked B+ yet, and I'll do that first. Should it be 123V?
2) Should I have more "screen" and less "brightness" or vice-versa? Does this affect focus range?
3) Should I test for shorts again? Maybe I caused one during the rejuv?

Puzzled.
 
adjust the contrast and the brightness right next to it to obtain a proper balance
Thanks, Dokert. But where should I set the "screen" control? I've read to set brightness in the middle and adjust "screen" until the raster just barely extinguishes. Do you agree?
 
Thanks, Dokert. But where should I set the "screen" control? I've read to set brightness in the middle and adjust "screen" until the raster just barely extinguishes. Do you agree?

Yes, set the fly just a hair below raster lines, and adjust the other two pots until they achieve balance. You may also need to tweak the focus a little too.
 
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