I have a poser for the group: I just obtained a fairly rare PP-32AR AC
power supply for the Hallicrafters ARR-5 and ARR-7 receivers. As an
airborne unit, its designed for 115VAC, 400-1000 HZ operation. I have
worked with modern 400Hz power supplies and appreciate the nuances of
same. I also have and use some rather "broadband" power transformers
that will run from 50 to 1000Hz power. The PP-32 was designed and
fielded in 1943 and would have employed technology of the era,
obviously. The transformer in this supply, given ratings, is arguably
the same size one would expect for a 60Hz unit; its fairly massive,
especially when compared to the compact units you'd expect in a modern
airborne supply. My question is, then, does anyone agree and suggest
that this unit might well work on 60Hz AC? As an aside, when I popped
the cover off, I noticed a chunk of ac lamp-cord soldered to the inside
of the Cannon input power receptacle as if some had run it (perhaps?) on
household current. Could these early 400Hz transformers have actually
originally been appropriate for 60Hz? I know (think?) that some folks
ran their APR-4 airborne receivers on 60Hz and they are of the same
generation of equipment. Finally, I note that there are no markings on
the transformer other than the pin designations. Also, there is a 80v
input tap on the primary for whatever reason; the book does not mention
it. I plan to try the 100w light bulb trick to see what might happen
but if anyone has any insights, I certainly like to hear them.
Tnx de Jeep/K3HVG