Hi Gang, IMHO,
A 3/8 wave inverted L is much much better than a GAP, but not as good as a
5/16 wave inverted L or shunt fed tower.
The GAP is not top-loaded and therefore has a poor radiation effenciency.
Like another ham stated it works good on 40, and gets by on 80 but is not
good on 160. That is why only a few "super ear" stations and W4s worked ZD7
when G3SXW was there!
We had many discussions on inverted Ls before going to PJ9Z some years ago.
If the horizontal part approaches a 1/4 wave, then the horizontal energy
dilutes the vertical energy for long haul DX. It is easy to feed a .25 or
.31 wavelength inverted L and keep the horizontal radiation to a reasonable
balance below the vertical components. If you have a 3/8 wave inverted L
and like it then don't change. I just wouldn't waste the extra wire to get
to nearly 200 feet overall when 160 feet or less will do the job.
Also don't forget shunt fed towers. They work well and with typical top
loading from yagi antennas, the pull the current up above ground. The
original articles by W4OQ were very good. Gary, K9AY, wrote a good shunt
feed article in "The Low Band Monitor" published by Lance, K0CS.
73 Merry Christmas and Happy 2000 to all
George K8GG
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