6 Meter Kit

6 Meter Kit adds 6 meter coverage to the HF6V.

The vertical wire from clamp (A) together with the adjacent section of the antenna form a short-circuited quarter-wave transmission line which cancels current flow. At the lower (open) end of this quarter-wave section a very high impedance is created that effectively divorces the upper part of the antenna on six meters, leaving only the lower section to radiate as a 3/4 wave monopole. Why 3/4 wave rather than 1/4 wave? Because the vertical plane pattern of the former breaks into two lobes, one at zero degrees and the other at 40 degrees, thus affording both low-angle and skywave propagation. Further, the radiation resistance of a 3/4 wave radiator is almost twice that of a 1/4 wave radiator, so for a given earth loss resistance the taller antenna should be more efficient, particularly when operated at ground level.

Adjustment for resonance or lowest SWR at a particular frequency may be made by adjusting the length of the wire or in the placement of the upper clamp along the antenna. In general, the wire may be lengthened to lower resonance or shortened a slight amount to raise it. Alternatively, the upper clamp (and the entire 6 meter assembly) may be placed higher on the antenna to lower resonance or slightly lower to raise resonance.

If the antenna is to be mounted more than a foot or so above the earth, several resonant radials may be required for low SWR operation on 6 meters.

Model# A-6.
Catalog# 277-12.