View Single Post
  #61  
Old 04-29-2020, 02:36 PM
Magnavox300's Avatar
Magnavox300 Magnavox300 is offline
..better in black & white
 
Join Date: Apr 2012
Posts: 288
Quote:
Originally Posted by JohnCT View Post
OC is right.

If you have a pulse at the fly and no HV, the rectifier tube is the next suspect.

What I would do if I didn't have a HV probe handy is to hold an insulated screwdriver at my fingertips and touch the cap of the HV rectifier tube. In a dark room, you should see the soft blue arcing between the tip of the screwdriver and the cap. Make sure the tool keeps at least two inches of plastic between your fingers and the metal shaft. If that CCFL tube lights, you should get a soft arc from the cap of the HV rectifier tube to the screwdriver.

If you see the arc, move to the anode connection on the picture tube and see if you have it there. If not, the HV rectifier tube or doorknob cap might be bad.

John
Thanks, did what you suggested and yes, I did get a soft good stead arc at the cap of the 1B3... nothing at the CRT anode.
I then tried a bunch of used 1B3 tubes I had laying around, but still nothing...
Then I turned down the brightness halfway, and got a picture!

I was testing all the time with the brightness up, which should have been fine, since it was all the way up when I first got a decent picture.

Problem is, picture is barely visible now, and blooms and goes dark if I turn up the brightness more than halfway...
Reply With Quote