I second Bob's last comment. Better to provide a LOW impedance path to
ground outside with gas tube or arc gap low impedance paths to ground
outside, then high impedance (to the AC component of lightning) paths via
drip loops and choke sleeves to the inside as commonly executed in
commercial antenna entrance cable protection installations.
73 ES DX,
Gary -- AB9M
-----Original Message-----
From: Bob McGraw - K4TAX
Sent: Thursday, May 03, 2012 7:51 AM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] TEN-TEC shack photos [flat braid; antenna switch]
The method suggested by Bob McGraw is to have each piece of equipment on the
desk connected to a common point, preferably the station power supply ground
terminal. I use #10 AWG automotive primary wire for this application. Lugs
on each end are crimped and then soldered. One jumper for each piece of
equipment to the common point or ground lug on the station supply.
On lightning protection, this should be outside of the house using devices
such as Alpha Delta systems, Polyphaser or arc gaps and these should be
applied to all feedlines and rotor control cables. Be sure the ground
system for the station or tower is bonded back to the AC mains ground and
this should be done outside of the house.
NEVER invite lightning into the house with the idea of running it to ground.
73
Bob, K4TAX
----- Original Message -----
From: "Gene Story - Earthlink" <gfstory@earthlink.net>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Thursday, May 03, 2012 1:57 AM
Subject: Re: [TenTec] TEN-TEC shack photos [flat braid; antenna switch]
My picture does not show where the braid connects and others might like to
know the rest of the story. I am definitely interested in feedback.
While I want to insure optimum path for a potential lightning hit, I did
have some worries that bonding these switches directly to my station
ground would be more of a hinderance as a ground loop path. Presently
that large flat braid goes to a small bar with two automotive spark plugs
threaded on it. The tip-caps of these spark plugs connect to my station
ground.
The idea is that I have not set myself up with a potential ground loop,
rather I have a high impedance situation with the spark plug gap under
normal circumstances. An abnormally high energy situation may jump the
plug-gaps, in the hopes of shunting what could otherwise be damaging to
equipment through other paths.
I admit not having enough theoretical background to know if what I
assembled is a sound idea. I put this together because the parts were
at-hand/easily fabricated, and this went together in a jiffy. But in the
interests of performing reasonable protection for equipment and operator
inside the station, have I set myself up for more negative than positive
results with the spark gap? And if this is plausible, would it be better
for each switch to have individual (direct or spark-gapped) paths as I
have with each piece on the desktop back which is patterned after Bob
McGraw's recommendations for grounding?
Gene / K7TXO
On Apr 29, 2012, at 10:29 AM, Merschrod wrote:
The shack photos are interesting all right. I liked the flat braid
ground
straps into an antenna switch cabinet.
BUT what is that neat little paddle under OZ1BII's Eagle? I can't make
out the manufacturer's name.
Kris KM2KM
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