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RE: tubes 6082 Raytheon

Posted by cpotl on May 13, 2020 at 13:18:39:
Nice looking amps! I also built the Dickie-Macovski OTL a few years ago, and it's been working nicely since. I followed the original power supply design, so there really is no transformer anywhere in the amplifier. I do have a slight hum, because of the necessity, given the power arrangements, of half-wave rectification. I've never got around to trying to deal with that but I assume I could moderate it with extra smoothing capacitors. I use AC for the heaters, and I don't think that is a significant source of hum. (I put the input tubes at the bottom end of the 120V heater chain and the 6082 output tubes at the "live" end.)

To answer djn the 6082 is not a drop-in replacement for a 6AS7 because it has a 26V heater. I think a 6080, differing only in having a 6.3V heater, is essentially equivalent to a 6AS7, though.