Hi Ray and all,
> real culprits.pay extra attention to ground loops.wall
warts are a prime
> cause of ground loops cut all the cables off the warts and
use only the cable
> and use a good quality 10 amp power supply for all the
ancillary station
> equipment. multiple antennas and feed lines should all be
kept galvanically
Actually the opposite is true. "Ground loops" occur because
various pieces of gear use common supplies. The more you
rely on one common supply,
> separated from one another till the cables are connected
at your main station
> bulkhead what i mean by separated is don't use the ground
for a 160m lnv l as a
> tower ground
I wouldn't know why anyone would want to isolate a tower
ground from a GOOD low impedance RF ground.
There are cases with "crappy grounds", such as counterpoise
or systems with a few radials (either elevated or gound
mounted), where bonding the RF ground to other grounds can
reduce efficiency and cause significant RF currents to flow
in other poor grounds or over cables to equipment, but the
real cure there is to improve the poor grounds. If a person
can't or won't use a good RF ground on Marconi-style
antennas or is using antennas with improper feedpoint
designs (such as end-fed wires, Windoms, dipoles without
baluns, feedlines improperly dressed near the antenna, etc),
then they might be forced to isolate the antenna RF shield
or ground connections from the rest of the system.
BC stations commonly ground everything together. Ham
stations should do the same, especially at building entrance
points. As a matter of fact, it is national code to bond
grounds on antenna cables to power line entrance grounds. It
certainly does not induce noise unless something somewhere
else in the system has a problem.
We can do almost anything we want inside the station at the
operating desk as long as the cables entering that point are
treated properly. The number one problem indicated when
noise levels atre affected by equipment wiring and routing
isn't ground loops. The problem is seriously bad RF cabeling
or bad antenna design.
73 Tom
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