At 01:32 PM 1/26/04 -0600, Didier Juges wrote:
If both dipoles will be used in the CW portion, I would tune the 40m dipole
first. Considering that the 80m dipole should have greater impedance at 7
MHz than the 40m dipole at 3.5 MHz, the 40m dipole will have greater
parasitic effect on the 80m operation, so you should probably adjust it
first. Now, if you want to tune the dipoles up in the band (such as the SSB
portion), or one CW and the other SSB, it makes probably less difference.
For many years, my main antenna system was three inverted vee dipoles off
the same feedpoint, hung in a tree behind our townhouse. Separate dipoles
for 10, 20 and 40 meters, the latter with W9INN coils to extend them to
cover a segment of 80. As long as the dipoles were arranged so that they
were not too close to each other (rotated 20 degrees or so from one
another, as viewed from above), I saw very little effect from changing the
length of one on the tuning of the others. Changing the included angles of
the individual dipole pairs seemed to have a much larger effect on their
resonance and feedpoint impedance than anything that was done to the other
ones.
73, Pete N4ZR
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