Help needed on Admiral 21D1 chassis tv

[bandersen]

I restored an Admiral set recently that also had good HV when I measured it at the CRT anode, but had a dim picture. Eventually, I tracked the problem down to a 470K resistor in series with the HV lead that had gone bad. I got erratic values when I tried to measure it. It probably had carbon tracks burned through it. Once replaced, I had a nice bright picture.

That resistor is mounted on the 1B3 rectifier tube base as I recall.
Good luck.

[kvflyer]

Originally Posted by bandersen

I restored an Admiral set recently that also had good HV when I measured it at the CRT anode, but had a dim picture. Eventually, I tracked the problem down to a 470K resistor in series with the HV lead that had gone bad. I got erratic values when I tried to measure it. It probably had carbon tracks burned through it. Once replaced, I had a nice bright picture.

That resistor is mounted on the 1B3 rectifier tube base as I recall.
Good luck.

Could be a good call Bob. When I did my 26R12, I just went ahead and replaced that resistor because I didn't like the way things looked under the socket. I may have avoided a problem by doing that! Resistors are cheap...

[Bill Cahill]

This appears to NOT be the problem with mine..
First, I was getting a steady 12KV on picture tube.

Next, last night, things got alot worse.
At first, after replacing the 6AC7 video amp, which had tested good, I got a rock steady, dark, but, watchable picture. I was monitoring B+.
Suddenly, voltage took a nose dive, and, picture got darker. Then my sync went nuts, and, it developed agc problems. Vert. rolled insanely, and, picture turned completely un wachable. Along with this sound developed a very loud buzz on all channels.
Picture was a twisty, turny mess, and, had also shrunk down to a 4" square in the middle of the screen.
At that point, I could barely see anything at all.
Sound buzz was so loud it drowned out the other sound..
My power supply was slowly going down at this point.
All said, and, done, apparently, something is pulling too much current, and, appears to be either overloading the main power supply, or, the boost.
Not sure what's going on here....
Had to get off to go to church at that time. I will probably try to start checking individual voltages today.
I think I'll start with screen of horizontal output, and, then work over to other circuits.
Something is obviously pulling way too much current.
Bill Cahill