At 08:12 AM 3/2/00 -0700, measures wrote:
>The reason to use Type-N or Type-C fittings at HF is to keep water out
>of coax. When used outdoors, PL-259s allow water to enter coax. .
>During a rainstorm, a friend of mine found a small puddle of water under
>his amplifier. Water was entering the braid of the coax via a PL-259
>that was outdoors, and then running down the braid to the amplifier's
>coax fitting.
To be sure. I have had several of those mysterious puddles appear on my
floor as well. It's always a real surprise when you finally realize where
all the water is coming from.
N connectors are expensive, hard to install correctly, and in general a
pain in the southernmost regions. I do use them, but only outside where I
need to keep the WX outside the coax and on frequencies where the high
return loss characteristics are important.
The best solution is no connectors at all. For HF use there is little
reason to do so. Short pigtails with spade lugs can be weatherproofed
easily and the connection is capable of John Lyles power levels. SWR is not
a problem when this approach is used with care. My old two meter, 16 yagi
EME array had only one (N) connector in the entire phasing harness, that
was needed to connect to the change-over relay. Inside the relay box I had
a couple BNC'S!!! My 40 meter 4-square has only a UHF connector on the end
of 200 feet of coax and that only to get into the coax selector switch. The
EME array was about 1.2 to 1 across the low end and the 40 meter 4 square
is about 1.15 to 1 across the entire band.
No power problems, no SWR problems, no WX problems, and the spade lugs only
cost about 10 cents at Checker auto! What more could a guy ask for?
73,
Larry - W7IUV
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