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[TowerTalk] static drainage

To: <towertalk@contesting.com>
Subject: [TowerTalk] static drainage
From: shr@medinaec.com (W0UN--John Brosnahan)
Date: Mon Jan 27 09:24:56 2003
Pete--

I really don't like high-value, small-wattage resistors for static
drain.  If you get a nearby lightning strike it is possible to
blow the resistor and never know it--then you no longer have
static protection.

If you are using monobanders then use shorted 1/4 wave
coaxial stubs.  They provide the DC shunt you want as well
as reduce your second harmonic by about 30 dB (as well
as high-order even harmonics).  If you need a broadband
static drain then use the ICE lightning suppressors.  They have
a DC drain from a toroidal RF choke that is better than a
small resistor--plus they have a DC block that may be useful
(or may not--depending on your needs for DC down the coax).

I think WX0B at Array Solutions carries the ICE units and I
think ICE has a patent on their static drain method--FWIW.

73--John   W0UN


>My question is -- is it worthwhile to install 1.5 megohm resistors inside 
>the relay boxes across each antenna jack, as is done in the Heathkit 
>switch, presumably to drain static electricity?
>
>73, Pete N4ZR


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