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Old 01-23-2012, 03:59 PM
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Electronic M Electronic M is offline
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Join Date: Jan 2011
Location: Pewaukee/Delafield Wi
Posts: 15,473
The DC at the grid is around -44 to -49 on my DMM (it varies between different power ups/warmup times) sam's calls for -60DC at the grid pin of the HOT. I don't have a functioning VTVM, and don't have time to take on fixing my busted one.
I recall that all caps and resistors between the HOT grid, and the osc. tested good on a DMM and an eye type cap checker.

I replaced the screen resistor a while back, and if I run the set with the plate lead removed the screen resistor will lightly smoke(it gets hot otherwise). The plate lead of the damper is at B+ regardless of the screen voltage.

The screen shoots up to B+ when the HOT is removed from the set.

It is a pain to measure the cathode current in my set, and my VOM has a bypassed blown fuse (I know it is bad for the meeter, and is temporary until I can grab a new one somewhere) so measureing the cathode is likely to smoke it if it is supplying all that current to the screen. I did insert my meeter in series with the HOT plate lead and got somewhere around 50mA (This is from memory, but I'm sure it was MUCH lower than the cathode current spec).

This set was given a complete lytic, white tubular ceramic, and plastic molded recap. I also replaced all maroon/orange drop types between from the osc. onwards through the the rest of the horizontal/HV stage. Also most of the maroon drops on the video board. All of this recapping predates the HV issue by months. I left all the original disc ceramics and all that I tested were good. There are some drops left in the horiz AFC stage though.

"there are two caps from the plate of the HOT, scope there see if one is getting weak."
I don't understand this statement can you please clarify. Also I believe it is verboten to measure the plate lead of the HOT?

Here is an old picture of the osc schematic for you all to digest.
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