[Lowfer] Re: Progress comes to the boondocks (finale, I hope)

[Lyle Koehler]

>Wondering how much C was needed to tune that one-turn loop?

RJELOOP1 said that I would need about 0.039 uF. I don't remember the exact
prediction, but that was in fact what the loop actually wanted. The coupling
transformer is an FT-50-77 core with two turns on the primary (loop side);
20 turns on the secondary. Theoretically it takes even more than a 100:1
impedance ratio, but that would be for an ideal loop in space, with a
lossless capacitor. The impedance at resonance looking into the coax side of
the transformer was actually pretty close to 50 ohms, according to my
homebrew analyzer.

It's hard to fine tune a 0.039 uF capacitor, especially when you're sitting
out there with a portable soldering iron and the loop swinging in the
breeze, trying different capacitor combinations. Someday when it warms up
again I'll try resonating the coax side rather than the loop side. That
should require only 390 pF. My gut feel says that there will be more core
losses that way; I haven't tried to analyze the situation.

Lyle, K0LR