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42-321 Questions
#16

(10-28-2016, 11:38 PM)Radioroslyn Wrote:  
(10-28-2016, 11:02 PM)Paperboy Wrote:  I ohm'd out the RF transformer (part #11).
The secondary gave 30 ohms but the primary
showed infinity. Is it easy to find this part or do I have to find another 42-321.
Thanks

I would wind 50 or 60 turns of sm magnet on the coil form like 36ga wire. It's untuned so it not super critical. Or you could use a rf choke in place of that winding and use a small mica cap like 50pf from the plate of the rf amp to the input grid of the mixer tube. Or this   https://www.tubesandmore.com/products/an...ube-radios

A new rf choke, would that be in series or parallel with new pico farad???
#17

The choke replaces the open winding, goes from rf amp tube's plate connection to the hv just as the primary did.

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
#18

(10-29-2016, 10:16 AM)Radioroslyn Wrote:  The choke replaces the open winding, goes from rf amp tube's plate connection to the hv just as the primary did.

Since I've never done this before I'll try the antenna coil way, thanks.




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