Quote:
Originally Posted by Electronic M
The 6ME6 is listed as a valid replacement in the sub books, but I'd be tempted to try the correct 6JE6 specified.
Early in my TV repair days I ended up selling a RCA 9T246 because I couldn't get rid of bad horizontal non-linearity.... Somehow I never noticed that the original 6BG6 had been replaced with a 6DQ6 or similar later H output, and apparently according to the next owner that was basically all that was wrong with it.
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I have NOS 6JE6 tubes of different versions (A, B, C), as well as the 6LQ6, and 6MJ6. Each subsequent tube model has a higher cathode current rating. I will try to adjust the efficiency coil first and then drop down to the next lower tube revision only if it doesn’t fix the non-linearity. Even the 6LQ6 is obviously less robust than the 6MJ6, which has not only a black plate for better heat emmisivity, it has two plate to top anode cap connections that are much thicker (more current , more heat), the top anode cap is also black, and the tube is taller (more heat tolerance again). The cathodes themselves must be bulkier to have a higher current rating, and so all of these differences possibly do change the tube characteristics enough to cause resonance issues required for the output stage to have the linearity the chassis designers intended.
