Topband: spark gap construction ideas for 160m tower

[Tim Duffy]

My quarter wavelength vertical tower (driven element in my vertical
parasitic array - see last 3 editions of the ON4UN low band DXing book) has
a shorted quarter wavelength of coax connected to the feedpoint. That keeps
the vertical at ground potential for lightning, etc. This is one method
cellular operators use for lightning protection. Easy and very
straightforward.

73
Tim K3LR

-----Original Message-----
From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of
donroden at hiwaay.net
Sent: Monday, October 7, 2019 9:49 PM
To: topband at contesting.com
Subject: Re: Topband: spark gap construction ideas for 160m tower

If you gap a pair of spheres .... graphite, brass, or stainless  
steel... typically the thickness of a credit card for a 1/4 wave  
broadcast tower at 1KW carrier / 4KW peak; unless you shield the gap,  
water WILL bridge the gap either side-by-side or stacked vertically.    
Rain drops are typically pure distilled water,  but if the water runs  
down a galvanized tower, all bets are off.    Make a rain shield out  
of a plastic Coke or Pepsi bottle  and replace a couple of times a  
year as you inspect all of your connections.

Don ( still doing Broadcast AMs after all these years ) W4DNR



Quoting Jim Thomson <jim.thom at telus.net>:

>> ##  Place  a plastic  cover  above  any  outdoor spark  gap.   Any
> bugs  will  be  fried.
>
> Jim   VE7RF

_________________
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector