On the QRP-L mailing list, a ham asks:
I know this should be a simple answer, but I’m having a hard time finding it. I am interested in building a EFHW coupler similar to the one on AA5TB’s site. He uses #22 AWG magnet wire.
I’m interested in using something less stout which I have on hand (e.g., #27 AWG magnet wire). Is there a calculator to determine how this would affect the number of turns on the transformer, or am I incorrect in thinking that it would make a difference?
Diz, W8DIZ, replied:
No calculator that I know of.
- Smaller wires have less current capacity before heating – bad thing.
- Smaller wires have less capacitance between windings (if same # of turns) – good thing.
- Wire size (for all practical purposes) does not determine inductance.