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Goofball_star_dot_etal

On 14/12/2009 15:28, wrote:
On Mon, 14 Dec 2009 15:15:48 +0000, goofball_star_dot_etal
wrote:

On 14/12/2009 11:00, wrote:
On Sun, 13 Dec 2009 23:48:25 -0500, Wayne.B
wrote:

On Sun, 13 Dec 2009 15:14:31 -0500, "Flying Pig"
wrote:

I'll try to find someone with a SWR meter here tomorrow morning before we
head out to our anchorage prior to going into the dock where we'll be
leaving Flying Pig, and give it a whirl.

One of the quirks of waterlogged coax is that it can exhibit a perfect
1:1 SWR ratio while transmitting little or no power because the signal
loss is so high that nothing gets reflected back to the SWR meter.

I also have the little cable and the mast-top antenna which proved the cable
at fault in the original explorations; it will be easy for me to get a boat
buddy to listen while I read some story or something on a remote channel and
see if that cured it. That shortie, BTW, is LMR400, so should be fine for
the test. I don't expect it's got much in the way of SWR issues :{))

OK

As to sagging power, with an 880AH bank, I doubt that's a problem,

Agreed but you could have a bad connection which is heating up under
load.

Accurate SWR measurements also require clear dry conditions. An
overcast day will affect the readings.

Probably a Ham's old wives' tale. Your average VSWR meter is not very
accurate, although still quite useful. This leads to all sorts of BS.
The device I use cost more than my boat..

Nope, not an old wives tale at all.

Work out the _magnitude_ of the change in electrical length of the
antenna due to water vapour for yourself.

http://www.kayelaby.npl.co.uk/genera...2_5/2_5_7.html