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Shortwave Converter
#1

Has anyone had any experience with an early thirties shortwave converter? I have a Deforest Crosley model 201B that has two tubes, a 27 and a 24A. It is almost identical to the Stewart Warner 301. What I am wondering is what is the output signal supposed to be or how would one determine it. It says nothing on the schematic.

Gregb


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.pdf Deforest 855B.pdf Size: 212.56 KB  Downloads: 204
#2

I've got the sw unit but never have used  it. I would just listen for it's output on the bcb. Don't remember if the convertor's dial is calibrated in frequency or 1-100. If it's calibrated in frequency use a generator set at the convertor's dial frequency to determine the best sensitivity by tuning the bc dial. This insures that the rf and osc are tracking properly.
Or
Bcb dial frequency= convertor's dial frequency - it's local osc frequency. So if you set the convertor dial at 2.5mc and use a well calibrated SW receiver and find the osc output at 3.5mc your bc dial setting is going to be 1mc.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#3

Usually these 2 tube units have a detector (27) and an oscillator (24) for output.

While not exactly the same, I restored one of these and tested it in a rare Northland console last month:

http://www.russoldradios.com/blog/archives/11-2016

My conclusion was that this was an interesting accessory that was not very practical for everyday use and that had been demonstrated by an early repair in which they had fixed the radio and simply unhooked the SW adaptor. But they are fun to play with.

"I just might turn into smoke, but I feel fine"
http://www.russoldradios.com/
#4

Well I have been messing around with this thing for a while now and I do seem to get some reception if the radio is tuned to 1mc and then the converter seems to work though rather poorly. I put some signals into it from my signal generator and its fairly close but does not seem to be very sensitive. I think we will call this an interesting novelty.

Gregb




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