K4800 (13" K900) wiggle after warmup

hackbar

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I have a K4800 that develops a static wiggle after about 30 seconds. It looks good when it first turns on. It seemed to start after I recapped this, but the geometry was so awful before the recapping it's hard to be certain.


Here's a video.

Any ideas what to check? What cap might be causing this?
 
Things that come to mind are geometry pots, filter cap. B+ voltage looks good?

Thanks,
Jason
 
that doesn't look like your typical wrong B+ hula effect. my 2000+ mile away remote hypothesis is the H. Hold needs to be wiped, and be mindful if it was set for a game, the TPG may have different needs. but you've also altered how multiples circuits on that monitor are going to work by replacing the caps.

I'm not proud of how this video came out cause I was doing it with a tripod and my hands were getting in the way but I'm sure you'll amass some intelligence for how to deal with K4800/4900s better afterwards. :p

I have to maintain a free play arcade and I've had the added bonuses of my diminishing cervical spine health and my car being out of commission the last couple weeks so I haven't had time to do anything particularly fun lately. I have some K4900s that went untouched, so I'll get another crack at doing my demonstration properly in the near future.
 
B+ is rock solid with only about 6mV peak to peak ripple

I wiped the h-hold pot a bunch, and no change.

I did notice that I can get the wiggle to go away if I turn down the black level pot. Any clues there?
 
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