Jim Lux said:
, the SteppIR looks like a dipole with a 10-20 pF
> capacitor
> across the feedpoint? In the usual scheme of things, I assume that you
> just make the elements a bit different length to tune out the C.
>
> Then, if you're attempting to go down to 3.5 MHz, the loading L interacts
> with the C, which superficially, you could tune out (make the L a bit
> bigger), but then, because the Q is high, you're going to have big
> currents
> and voltages in the LC combination?
I wanted to modify a 2 element SteppIR Yagi (the regular one)
for 30 meters (as a dipole). Since I would be running only 100 watts, the
voltage was "only" a coupla thousand volts. The scheme might
have been workable (not easy but workable) if it weren't for
the 25 pF of shunt capacitance. With a couple of thousand
volts across this "capacitor", the "dielectric" would probably
be toast.
I elected to put up a 30 meter vertical instead.
Rick N6RK
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