• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Is this a good interstage transformer?

m6tt

Member
2007-08-08 12:12 am
I recently picked up a giant and excessively overengineered radio from the second world war. It was a superheterodyne, but it used a choke power supply, and surprisingly, a 60-600-6000R SE output. The output transformer is a Thordarson, it lists a gap for 30ma dc, and an 8,000 ohm primary. Frequency response (as listed on the transformer's pot) is 75-15k, I'm assuming at one to three db. The model number for the transformer is T-46789. The chassis of the radio is stamped 1943.
 

m6tt

Member
2007-08-08 12:12 am
it did come from a military radio, probably made before pearl harbor. I was wondering if it would work well for phase splitting in an instrument amplifier...70hz is below low E, and I imagine it'll play lower notes, albeit quieter. If so, would I hook up the 60 ohm secondaries to the next grid? or the 600s or 6000s? I understand a low impedance drives a high impedance, but I also understand the transfer gets lossy as you increase the difference.
 
So what became of your project and the radio?
I think I may have the same output transformer here if you need to make a pair. I also have some interstage xformers that I have no matches for if you still want to experment with a single channel IT xformer driven amp.
I'm interested in what became of the radio, since the xformer I have is from a military radio I took apart when I was 10 years old and I'd like to find another.

I recently picked up a giant and excessively overengineered radio from the second world war. It was a superheterodyne, but it used a choke power supply, and surprisingly, a 60-600-6000R SE output. The output transformer is a Thordarson, it lists a gap for 30ma dc, and an 8,000 ohm primary. Frequency response (as listed on the transformer's pot) is 75-15k, I'm assuming at one to three db. The model number for the transformer is T-46789. The chassis of the radio is stamped 1943.