At 08:58 PM 11/6/97 -0500, you wrote:
>Now that we've discussed using braid as a ground, what are the opinions of
>using #4 or #6 as the ground? I have also quit using braid but have gone the
>way of using the heavy stranded stuff, not the fine cable that is used in
>auto jumper cables. I've also known poeple to use copper pipe.
>Jim Bruce/NV3V
>brucecom@shore.intercom.net
I am not expert on this subject, but try to follow the pack. One of the
things I don't not like about braid is that it seems to deteriorate after a
few months. An old timer, W0CY (SK), told me that braid was the worst to
use for a ground and that either solid copper wire or copper strap was
preferred. He mentioned that corrosion of the braid would bring the
resistance of the wire up thus causing a higher resistance. Not a good deal
for grounding, of course. He alwasy advised to use either large diameter
copy wire, #12 or more, or copper strap. So, I have used copper roof
flashing that comes in three inch rolls. I have had the rolls cut to one
inch and have that. Also, I have used a roll of copper tubing you can get
from any hardware store.
When I was working in Broadcasting, a station in town burnt to the ground.
All of us got together and got them back on the air. We took the AM
transmitter out of the rubble, hosed it off with water, opened it up to dry
for a day (it was July in Kansas with stiff winds) and then put it back on
the air. We mounted it on a packing pallet, ran 1/2 inch rolled copper
tubing to the tower base (about 150 feet), I got some RG8 out of the garage,
drove in two ground rods through the parking lot and attached the ground
with copper pipe, and put it back on the air. We placed a tent over it for
a week until they could get a trailer in for the station. It survive
several thunderstorms rigged up like that until they could get the station
rebuilt. I know the tower took a direct hit at least twice during that
time. No problems.
So copper flashing and pipe works for me. Works better if you silver solder
the connections, but I have also gotten away with clamps.
IMHO and limited experience....
Lee
k0wa@southwind.net
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