[Skimmertalk] lightning protection for skimmer

[Drew Vonada-Smith]

Contest Friends,

 
As a reminder to all, use of a lighting arrestor is a good idea for protection.  But an arrestor alone does not offer good protection unless system wide issues are considered.  The arrestor makes sure that the coax center to shield surge voltage is limited.  But it does not insure that the surge common mode rise of both lines with reference to the receiver is limited.  

 
The best way to insure this is have the arrestor, the radio, and all other connected gear use the same single ground connection, including power supply mains plugs.  And, to not attach additional unrelated grounds.  The best place for this single ground if possible is the power system main entry ground.  One usually can't achieve this perfectly.  But get as close to this description as possible.

 
This detail is nearly as important as the arrestor itself.  Don't overlook it.

 
For more explanation, google and read the good works by K9YC, W8JI, the new ARRL ground book, etc.  Or email me.

 
73,
Drew K3PA
 

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Message: 1
Date: Fri, 15 Jun 2018 16:50:12 +0200
From: dd5xx at web.de
To: "Reflector Skimmertalk" <skimmertalk at contesting.com>
Subject: [Skimmertalk] lightning protection for skimmer
Message-ID:
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Hi all,

I'd like to hear what kind of protection measures you guys take for your skimmer. I am preparing two skimmers, both are installed inside the same housing with lots of additional stuff like pre-amps, filters, network switch, mini computer, etc. Each skimmer is fed with an active antenna "mini-whip" which will be installed about 7m above ground level or 5-6m about roof level (which is at 10m height). The value of this box is about $2000 and the stuff is very sensitive. I am afraid even a nearby lightning strike could destroy quite everything inside the box. What measures can I take next to the usual lightning protection I am used for all kind of antennas (grounding rod)? is there anything special you can suggest for this operation and which won't negatively affect received signals ? Something like a discharge protection and if so where should I install it?

looking forward to your comments. Have a nice weekend.

73
Saki, DD5XX


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