I as well at the bottom of the tower mounted to red insulators. 16" Buss bar
and 9 polys mounted to it. Then coax into shack. I never unhook anything.
As mentioned, the buss bar should be connected to the house ground, and I also
have a ground ring around each tower with 9 rods all shot to the ring and not
clamped. Keep it all on the same potential.
73 Dave n4zkf
-----Original Message-----
From: TowerTalk <towertalk-bounces@contesting.com> On Behalf Of Jim Brown
Sent: Monday, December 15, 2025 4:49 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] lightning arrester suggestions
On 12/15/2025 10:13 AM, jim.thom jim.thom@telus.net wrote:
> The ICE, now Morgan arrestors work superb. They use a static drain
> resistor, then a DC blocking cap, then the shunt inductor, then the GDT.
I like this circuit.
I still have a fairly large copper panel full of Polyphasers that K6XX built
for me in his shop when I moved here 20 years ago, but they're not repairable
and a PITA to replace -- it takes two people to do it, one on each side of the
wall.
I had to do it often enough that I added a panel in a large Hoffman box using
arrestors using this circuit that Array Solutions was selling.
They are repairable, and W6GJB made me some mounting brackets to make that
easy to do.
Arrestors can be blown by too much voltage across them. Like when I transmit
into the wrong antenna. Or a lightning event.
It's important to remember that arrestors fulfill two distinct functions.
First, to short the center to the shield, second to bond the shield to the
facility ground system. Because voltage is induced inside the coax by current
on the shield, arrestors must be installed in close proximity to the receiver
to protect the receiver and the station. An arrestor at the antenna cannot
fulfill that function.
AND they can't protect much of anything unless they, and the entire premises,
are properly bonded.
BTW -- in my professional life in pro audio, we had to deal with the safety
certification requirement for any installed systems that were to be inspected,
and it came to light that almost none of the equipment we need to use for high
quality systems were certified. At that time (about
25-35 years ago), there were three recognized testing and certification
agencies -- UL, CSA (the Canadian agency), and ETL (Electrical Testing
Laboratory). UL, based in the US, was VERY expensive, which was why smaller
companies didn't spend the money to get certification, and those that did went
to CSA.
The pro audio industry got together and pushed UL to reduce the costs
associated with their testing, and some went to ETL. It took about five years,
but eventually nearly all of the gear we needed to specify carried one of those
listings.
73, Jim K9YC
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