I picked up an Admiral 17T12 with good audio and video a couple of years ago. At that time, I pulled the chassis for a quick look and a few pictures, then put it away. I took it out two days ago, but now it has no video at all.
I thought this would be an easy fix even for me with little expertise in electronics.
So I started with the tubes (I got an EMC 213 last year). I found one bad 6AU6 and replaced it with a spare used tube. Then the HV rectifier 1B3 showed shorts in two positions where it shouldn't be shorting. I pulled a 1B3 from a non-working set. This 1B3 was apparently OK two years ago, and it passed the short test, but on the emissions test the needle didn't even budge. I tried the tubes back in the set, but after several minutes there was no glow and no heat from either one.
Is the test failure of both tubes a coincidence, am I making an error in testing, or is the test instrument failing? I had no problem with a couple of dozen other tubes.
I'll be grateful for any advice. I've apparently forgotten how to embed images, but here are some picture links.
- Winky
My EMC 213 set up:
https://picasaweb.google.com/lh/phot...eat=directlink
Testing instructions and 1B3 data:
https://picasaweb.google.com/lh/phot...eat=directlink
Excerpts from Frank's Tube Data:
https://picasaweb.google.com/lh/phot...eat=directlink