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Old August 24th 03, 04:43 PM
David Robbins
 
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"Ken Bessler" wrote in message
...

"David Robbins" wrote in message
...

"Adam T. Cately" wrote in message
...
SNIP

I haven't read the rest of the thread, but here's something

glaringly
obvious...

Grounding will be easy when I get around to it - I have
baseboard hot water radiators that I can ground to.

NEVER ground to hot water pipes - ALWAYS use the cold water pipe,
as it goes directly to the earth outside the building. The hot water
pipes are routed through the hot water heater(s) and are NOT a direct
path to ground.


first a couple of truisms:
NEVER say NEVER.
NEVER believe anyone who asserts an ALWAYS.
In the end an easy job is rarely as easy as you first thought.

That being said, NEVER rely on pipes of any kind for safety (either AC

or
lightning) grounding of equipment, ALWAYS run your own wire to the

proper
ground rod or electrical service connection as required by electrical

codes.

RF "grounds" are another problem. The problem here is to remember that

any
conductor more than a small fraction of a wavelength will have currents
induced in it and thus have a different voltage at one end than the

other
when exposed to an HF RF field. The real aim here is two fold: First,

to
provide a low resistance path for 'ground' currents back to the antenna

end
of the feedline so the currents in the feedline can be properly

balanced.
Second, to keep all equipment and personel in the antenna field near the
same potential to prevent injury and reduce interference.



Ha! Great point!

I'm planning on buying a Radio Shack outlet tester (22-141, pg 238 of
the last catalog) - if it shows my outlets are configired properly, I plan
on
running a heavy insulated ground wire from the outlet to the pipe (8").

Does this sound right to you? As far as RF goes, I can touch *any*
component of the system and not see any DC current, SWR or other
changes at all when transmitting so I guess I've got a pretty good RF
ground already.

Then there is the performance issue - the solar numbers haven't been
very good for some time but yesterday I worked stations coast to
coast on 20 & 40 with 5 watts and got some impressive signal reports.
So, whatever I'm doing, it seems to be working OK.

72's all De Ken KG0WX/QRP


tying the radiator to the electric service neutral probably won't hurt. if
the radiator is plumbed with metal pipe and is up to code they are probably
tied together somewhere else also. and its always a good idea to be sure
your outlets are wired properly, especially in older homes.

if you can touch stuff and not see any changes that probably means that you
have a low enough resistance connection back the the feedline point at the
antenna. that is where lots of people mess up, they ground the shack end of
the coax, but then connect just the center conductor to a random wire or
something like that outside. this arrangement forces the return current to
flow through ground, the shack equipment, back out the outside of the coax
and then back inside the coax to complete the circuit. this causes all
sorts of problems like the infamous rf burns from the key or mic,
interference to nearby tv, stereo, and computer equipment, etc. even
balanced lines and antennas are susceptable to this. if the antenna isn't
really balanced (say one leg is near the house the other is in the clear)
the unbalance in the return path can cause current to flow back through
wiring in the house to get back to the feedline.

with the poor solar conditions right now you are probably doing just fine,
just be sure you have a good safety ground and enjoy.