Hi Paul:

The Loudenboomer was acquired by Hallicrafters, so the HT-45 and the
Loudenboomer should be very close to the same.

I do not have the manual, but the power supply should be conventional.
Probably about 2,500 volts for the plate supply. The filament supply
generally is on the amplifier chassis - to eliminate voltage drop on the
high current filament cables. Only other thing would be the bias, and that
is often supplied by diodes in the cathode - or zero bias.

In short, you can copy almost any high voltage power su0ply for a similar
tube final. There are a few high voltage transformers with high current
that are only 120 volts. High power guys avoid them like the plague and you
can get them often for hauling them away. It will suck power out of a 120
volt receptacle like a 1500 watt heater, and if lights do not dim when that
happens, you should be ok.

The Loudenboomer was a pretty amp - although i recall it does not have tuned
input. You may want to build insert a tuned input if you are using a solid
state driver.

73, Colin K7FM