In Reply to: RE: Wait. Weren't you talking about 60Hz hum from filaments? (n/t) posted by Tre' on September 13, 2016 at 09:44:44:
5. Filament supply for the 845. 60Hz if it's AC
That's not correct, at least not in tubes with large filament structures like the 211 and 845. Those tubes also generate considerable harmonic energy at 120 Hz. I first discovered this when I built a circuit attempting to null the 60 Hz in a 211 amp. It worked, but there was still too much 120 Hz energy. I eventually discarded the whole idea. It seemed futile to try to duplicate the entire harmonic signature being created by the filament for purposes of nulling. That was when I moved to DC, and later to ultrasonic heaters.
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Follow Ups
- Filament hum - Triode_Kingdom 10:40:52 09/13/16 (8)
- RE: Filament hum - Tre' 12:45:28 09/13/16 (0)
- RE: Filament hum - vinnie2 12:42:12 09/13/16 (6)
- RE: Filament hum - Triode_Kingdom 19:10:38 09/13/16 (5)
- RE: Filament hum - vinnie2 03:18:40 09/14/16 (4)
- RE: Filament hum - Triode_Kingdom 12:17:24 09/14/16 (3)
- RE: Filament hum - vinnie2 13:05:24 09/14/16 (2)
- RE: Ultrasonic Link - deafbykhorns 10:20:56 09/15/16 (1)
- RE: Ultrasonic Link - vinnie2 12:51:13 09/15/16 (0)