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I picked up this beauty of an old radio at auction for next to nothing. The cabinet is in great condition, but the electronics are another mess entirely.
Most of it is original 1929 paper wound caps, with a nice chunk of tar to deal with. I said most…and this is where my first stumbling block is! I think someone last worked on this radio in the 50’s/60’s, possibly with another attempt being made later on (with disastrous results that I’ll get to).
Pictured below is what is listed as the “1st R.F. Transformer” in the schematic…though it has been changed, here. I tried to trace all the modifications made, and my altered schematic is below.
Now, from what I can gather, in the original schematic the “RF transformer” should really be labelled as an “antenna transformer”. It is used primarily to boost antenna signal going in to the first stage. From what I can tell, the primary was removed entirely and the secondary was attached across ground and the antenna lead. I figure whoever worked on this unit last found the dreaded green dot disease all over the primary…and wasn’t so concerned about signal strength (stations were a lot stronger by the mid 70’s) so he just removed the primary and the whole idea of an antenna transformer.
My question is…how many turns do I put on the primary? Assuming I can get this thing back to working order, I’d like to have it in a state that it was originally in.
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