Topband: re:topband switching in extra antenna length.

[Lee K7TJR]

Myself and K7zum have very successfully used a simple trap to wire  load his
shunt fed 55 foot tower with a kt34xa on top for  160 and 75 meters... It
has worked so flawlessly we have forgotten the design details.. What we seem
to remember is that we used two 7.5 kilovolt doorknob capacitors (icant
remember the value but I think they were270pf or 500 pf.)mounted in parallel
inside a piece of 4 inch pvc pipe with a pipe cap on one end. We hung it
with the cap up which keeps the Oregon moisture out of the capacitor
inside... We wound a coil with #12 on the outside to resonate it for 75
meters keeping in mind to keep the diameter to length ratio about 1 to 1 for
a good Q factor and high voltage spacing of the wire... The antenna system
has been in use several years and used for  several contests without any
failure... Even when one of the ops accidently gave it over 2kw from the
Titan amp..  No switches, no relays, no control wires, no problems...  good
luck    Lee   K7tjr