Pete,
Best bet for power line induced lightning surge is to add an in-line
inductor between the power company and the MOVs. I gave details on same
(and may other tips on preventing lightning damage from HF-UHF) in "VHF/UHF
World-Protecting Equipment", Ham Radio Magazine, June 1985. pp. 83-94.
You need an inductor with an inductance of 50-100 Microhenries. This is
easily done by winding 120-170 turns of #18 AWG (or larger) wire on a 1"
diameter dowel. Do not use ferrite! The MOV will then do the cleanup.
73,
Joe, W1JR
At 09:31 PM 3/20/2002 -0600, Pete Goudreau wrote:
>After some research, including towertalk archive searches, it looks
>like the only protection units out there for control and rotator
>cables are shunt types - Polyphaser and I.C.E. come to mind. While
>researching the topic, there also seems to be a goodly number of
>stories of lightning surges getting past exploding MOVs in said
>protectors and blowing up most of the equipment in the shack.
>
>Not being much of a fan of MOVs in the first place, I figured there
>had to be some series type protectors out there somewhere but I'm not
>finding them at all. Design is relatively easy but extremely
>difficult to test correctly.
>
>Anybody have any suggestions as to the safest way to keep the lines
>connected but well suppressed?
>
>Thanks in advance,
>Pete, AD5HD (ex-WB5RKC)
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