>From: martin38945@juno.com
>By the way, those folded dipoles were fairly easy to tame with a
>matchbox so one cut for 80 would work pretty well on all bands.
Hi Martin, when twinlead is used for the antenna, the currents
in the adjacent wires need to be in phase or else dielectric
losses will occur. Unfortunately this condition only exists
for frequencies that are an odd multiple of each other, like
3.33 MHz and 10 MHz and 30 MHz, or 7.1 MHz and 21.3 Mhz. A
folded dipole on double it's design frequency is a worst case
dielectric loss and tries to act like a shorted transmission
line. The SWR is sky high and losses are tremendous. Using an
antenna like this for QRO will surely blow something up. In
short, a folded dipole should not be used on even harmonics.
73, Cecil, W6RCA, OOTC
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