I acquired this amplifier in the Fall of 2004. When I first saw the pix I suspected that it was a Hallicrafters HT-33 that had been re-packaged. It turned out that it was. The RF deck had been saved intact, but almost all the power supply components were not original Hallicrafters. The owner had made a very nice cabinet for the RF deck, assembled almost totally with "pop-rivets." The power supply was on a galvanized sheet metal chassis that was a bit light for the weight of the HV transformer and other components, again assembled with pop-rivets. A very nicely formed and welded cover had been made of heavy gage perforated stainless steel. It may have been an HT-33A, and upgraded to an HT-33B.
Pix "as found"
pix after cleanup and rework of the power supply.
The 4 10kohm 50watt dropping resistors for the screen voltage had been located under the chassis, with a fan, but the excessive heat in the enclosed space had driven 2 of the resistors to failure. New ones were purchased, and they were placed above the chassis, with the fan on a new bracket. The rectifiers were a string of 11 silicon diodes per leg, with equalizing resistors and capacitors, as was common some 15-20 years ago. New 2 HV diode modules were purchased from K2AW's "Silicon Alley", and a bracket was fastened to the transformer with 6-32 hardware into tapped holes in the cast iron end bell.
It is now, in Jan. 2005, operating well on the air, presently driven by a Hammarlund HX-500 transmitter.
to see the HX-500
Much later, I decided that the knobs should have more descriptive labeling, and added some decals. I have been using it with a KWM-2A, often as net control on the Vintage Sideband Net, on 20 meters.
I swapped this amp off in 2009
Radio to go to HOME
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And remember: "They don't make tubes nowadays like they used to..."
This page last updated on 05/25/2009.