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Larry Larry is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 5,275
Default stainless steel foil instead of copper for grounding Ham radio?

Brian Whatcott wrote in
:

I have silver at 0.0159 microhm meter at 20 degC
copper 0.0168 microhm.meter
gold 0.022 microhm meter

So gold may not be not quite as conductive as the best, but it

STAYS
at that value - no tarnish....

Brian W



I wish you guys would worry much more about "series inductance"
and lots less about how expensive you can make the damned ground
strap.

Look at your ground strap and follow it down to whatever is
supposed to be "ground" on your boat.

1 - Are there any sharp corners or folds back over itself to make
it look really neat, like boaters love their stuff?

This is bad, very bad. Every sharp curve increases the series
inductance, and inductive reactance. If it bends 90 degrees, you
have a 1/4 turn coil in series, raising the ground at the tuner
MUCH more than the total combined resistance of all the metal
chemistry in the circuit, which increases with frequency.

All turns in the ground strap should be as large a diameter as
you can make it and very smooth to reduce series inductance. It
should be routed in as straight a line from the tuner to the
ground as you can make it, for this same reason. This strap is
PART of the antenna. It radiates like mad when you're on the
air, into the bilge wiring, the reason why the LEDs in the DC
panel all light up when you talk. They're detecting the RF
induced into those DC cables in the bilge.

Now, let's put away the periodic tables and go reroute the ground
straps, taking off all the pretty tywraps and making them as
straight as possible, shortening them as much as we can.

Larry W4CSC and other fine old calls since 1957
--
Bruce will be by to inspect your installation, shortly.