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Well I replaced the 6BG6 screen grid resistors. The 22K had drifted up to near 35K and the 27k in parallel didn't drift at all.
Now the set draws way to much current. At 117V its now drawing 2.88 amps. Width is only controllable with the drive control. Any higher than I get those vertical lines on the right side of the screen.
The width coil did ohm out fine but there is 0 change to the width on the screen. Same with the linearity control, it has no affect.
Brightness is still too bright and only gets a tad brighter before blooming. I'm getting 30 volts now the cathode on the DC restoration half of the 6AL5 vs 20 volts before. Should only be about a volt.
What the heck is going on? Voltages are just so high in the set and I'm running out of ideas. The sync tube V16 6SJ7 its plate is still 310 volts. Should be 250, but my B+ off the rectifiers is 30 volts high. That still leaves an extra 30 volts that shouldn't be there. Its been recapped and those resistors check out. The contrast control previously had to be set about 1/3 to get sync and a watchable image. Now it needs to be set 2/3 up and has almost no range before loosing sync. I really need to figure out where I'm getting extra voltage from because its screwing up the bias on many tubes I'm sure.
If I could only get the set to draw the current I was getting before replacing those screen resistors on the HOT I'd run the set as is but with it drawing this amount I know its the horizontal output drawing that extra current. Resistance check on that 6bg6 screen is 12K and about 278 volts with the drive set about halfway.
This set just keeps having problems and its getting very frustrating.
Wish me luck..
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Matt Davala
Last edited by Davala; 10-22-2020 at 01:44 PM.
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