W4RNL gives advice on traped dipole for 160 and 80m and sugests tuning trap
for resonance on 3,4 MHz, well bellow 80m band? I'll assume that 3,75 MHz
figure would be much better for wide USA 80m band. With reasonable Q=200
and 100pF doorknob capacitor we get 88 kOhms of isolation on resonance.
With full legal power we might expect about 2kV at each trap giving less
than 100W loss (or 0.25dB in the present confused S debate) or 94% efficiency.
Losses will be lower at 160m as equivalent coil resistance is about 1 Ohm.
This simple math is done with unrealistic assumption that dipole is high
enough on 80m and exibits 73 Ohms impedance.
73 de Mario, S56A, N1YU.
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