At 01:13 PM 5/2/98 -0400, Joe Reisert wrote:
>Todd,
>
>Yes, that is a good idea but it's not new. In fact, it is used extensively
>in commercial circles and every major commercial producer of Lightning
>Arrestors now offers them, even PolyPhaser that used to poo-poo them.
>
>The only real drawback to this technique is that it is essentially narrow
>band so you would need a separate arrestor for each band. That is practical
>for the VHF and UHF bands (where monoband antennas are the rule) and even
>for some dualband VHF/UHF omnis (like 146 and 440 MHz where the quarter
>wave short on 2 meters is 3/4 waves at 440) but not too practical for the
>triband HF beams etc.
I recall that some multiband verticals used to have a multi-turn coil to
ground at the base of the antenna, as a static drain. I always assumed the
inductance had to be accounted for in the matching scheme used. Don't the
hairpin matches used on some antennas (TH-7, C4, etc.) also provide a DC
short to ground? My Heathkit antenna switch has 1.5 megohm resistors to
ground from each antenna feedline center conductor, and the circuit
description says they're to "help bleed off any static." Sounds like there
are lots of ways to achieve this, yet my high tribander still fries
something fierce in some (not all) rainstorms.
73, Pete Smith N4ZR
n4zr@contesting.com
"That's WEST Virginia. Thanks and 73"
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