The 205CA is on a 34 foot boom. W2PV has shown that with this length boom
on 20m, usually you can get good gain OR good F/B but not both at the same
time. The older 205BA had good gain, approx. 6.9 dBd but only 15 dB F/B.
The newer 205CA has aprox. 6.5 dBd with 30 dB F/B. The 204BA has approx.
6 dBd and 27 dB F/B on a 26 foot boom. I do have a model of the 205CA
which acheives >7 dBd with approx 20 dB F/B but the impedance is around
15-20 ohms, and the bandwidth is limited. If anyone is interested, I can
provide this. I do not think that you can gain much by using 4 elements on
a 34 foot boom. I have tried this, and you end up with the same tradeoffs.
73 Roger WB0DGF (Hy-Gain)
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