Posts: 50
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Joined: Dec 2014
City: Wyoming, PA
Hello all, I have an open secondary winding on my oscillator coil, item #16 in the parts list with a secondary resistance value of 3.4 ohms. I counted 16 turns of original transformer or magnet wire, which is about the size of a human hair. The smallest transformer wire I have is 33 AWG. When I restring the secondary coil with 16 turns as original, I am measuring 1.2 ohms. So, what is more important here, the resistance value (which I think they used as a measuring reference) or the inductive reactance which is how this coil is actually used? I know the number of turns affects the inductance, but I get the wrong value when checked with a vom. Thoughts?? Thanks!!
Posts: 7,212
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City: Roslyn Pa
Inductance trumps the resistance. The resistance is going to be different as your wire size is larger. If you don't have enough turns it won't oscillate at the low end of the band. Coil is used to couple feedback from the cathode to the grid and is not in a resonant circuit.
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
Posts: 50
Threads: 14
Joined: Dec 2014
City: Wyoming, PA
So should I go with my rewound coil with 16 turns measuring 1.2 ohms?? Thanks
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City: Jackson, NJ
Forget ohms. Go for the turns. Also if you don't have the proper wire (often gauge 42) I recommend you buy a spool, with 30-s radios comes handy more often than I'd like to see it.
If the coil is not a part of the resonant tank the turns is the only thing that matter.
If it were, than everything would matter, turns, length of winding, thickness etc.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 50
Threads: 14
Joined: Dec 2014
City: Wyoming, PA
Thanks for the help gents!!!
