Tube Amps / Music Electronics
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|1/12/2004 9:12 AM|
|saros141||How robust is hammond iron?|
I'm planning out a project and I have a Hammond 270AX to use as a power transformer - it's one of the earlier ones from the 60's, with the metal badge, NOS.
When I add up my filament voltages, I get 2.5 Amps, and the filament secondary rating of the 270AX is exactly that, 2.5A (according to their site that is, I'm assuming if the specs have changed they would have assigned a different model number). This doesn't take into account the pilot light, which I expect would draw an additional 150 to 300 mA.
Can this PT handle its maximum filament current (or even a hair beyond) for several hours of continuous use?
I have a nice potted Triad filament transformer I can use if necessary (it's almost as big as the PT). I could run the filaments of the output and preamp tubes off it, while the filament secondary of the PT would be left for the rectifier and pilot light (everything is 6.3V). Then I wouldn't have to use the virtual center-tap with the pair of 100 ohm resistors on the PT's 6.3V secondary - I can just run the Triad's center tap to the cathode of the output tube (it's a single-ended topology). If this method is potentially quieter maybe I'll do that.
So, to those with good experience with Hammond iron - what would you do?
|Wild Bill I'd just use the Hammond!|