10-21-2014, 04:18 PM
I was a little confused about the English dial myself, but do know about the red dots. I am guessing that if I want to read the meter in mutual conductance, I set it to one of the dots within the range of what the chart calls for? And, that I use the "replace-?-good" reading I set to the number listed? Another question I had is about the Gm number; is this the minimum value for pass-fail?
I assume this tester has been idle for years, maybe decades. I havent really decided if any of the controls are dirty or if it is the way it operates. I made a few quick checks, but dont have the 1k per volt meter handy, so I used my Fluke 77. Plate B+ is really high, just under 200v, screen voltage is right on at about 131v. Reduced screen also on target at about 57v. Bias was a little off at -41v. Grid signal also right on at 2.5v ac. I know this may be off some due to not using the proper meter for some of the tests, but gives me an idea of whats there. Line control did seem a little flaky - seems to run high, but it will adjust with a tube in a socket for testing (6V6GT).
I pulled the cabinet to visually check over, and found the 83 tube replaced with silicon diodes (they did use a tube base), 5Y3 was in place. This could explain the abnormally high plate voltage and the flaky line adjustment. Still has an old E-cap across the meter. I saw where the english control had "been into", but it does seem to work fairly decent. This is as far as I have gotten. I also appreciate the link to get an updated tube chart. I noticed the lack of some newer tubes such as 6BQ5, 7591A.
Thanks for the replies so far.
I assume this tester has been idle for years, maybe decades. I havent really decided if any of the controls are dirty or if it is the way it operates. I made a few quick checks, but dont have the 1k per volt meter handy, so I used my Fluke 77. Plate B+ is really high, just under 200v, screen voltage is right on at about 131v. Reduced screen also on target at about 57v. Bias was a little off at -41v. Grid signal also right on at 2.5v ac. I know this may be off some due to not using the proper meter for some of the tests, but gives me an idea of whats there. Line control did seem a little flaky - seems to run high, but it will adjust with a tube in a socket for testing (6V6GT).
I pulled the cabinet to visually check over, and found the 83 tube replaced with silicon diodes (they did use a tube base), 5Y3 was in place. This could explain the abnormally high plate voltage and the flaky line adjustment. Still has an old E-cap across the meter. I saw where the english control had "been into", but it does seem to work fairly decent. This is as far as I have gotten. I also appreciate the link to get an updated tube chart. I noticed the lack of some newer tubes such as 6BQ5, 7591A.
Thanks for the replies so far.
If I could find the place called "Somewhere", I could find "Anything"
Tim
Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44