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Old February 21st 05, 03:48 PM
 
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Hamsticks have a nasty characteristic. A 75m Hamstick is
self-resonant before it gets to 40m. A 40m Hamstick is
self-resonant (~9 MHz) before it gets to 30m. Self-resonance
is the frequency at which the inductive reactance equals the
stray capacitive reactance and results in heavy losses. I
don't know the self-resonant frequency for a 30m Hamstick
but I'll bet it's lower than 14 MHz. .......


Yea, you never want to use a low band stick, for upper
bands...Those sticks *must* have a decent stinger whip
to do any good. No capacitance, no worky....
But using a upper band stick on lower bands, by adding
more stinger works great. The antenna gets better and
better, as you drop bands, and add stinger length...
IE: a 10m stick tuned to 20m, by adding 2 more ft of
stinger works very well. Better on 20, than 10, if the
stinger on 10m, is a short stub..
Ditto for 20 to 40, etc...
When I ran a 6 ft 20m stick on 40m, using a 5 ft
stinger, that antenna was nearly as good as the
*average* bugcatcher. No joke. It kicked butt...
But that stick had the coil windings at the top, and
not evenly wound over the whole height, so current
distribution was real good. Much like a lumped coil
antenna. Just a thinner coil....MK