"David" wrote in
:


The noise level does not change when I turn the beam 360 deg.

You did give S meter readings, but with respect, they are meaningless in
the context you have given. Radios are not iniversally well calibrated,
and most hams could not tell us what radio setting (eg PREAMP ON/OFF) put
the radio in the calibrated mode.

Remember that a directive antenna does not reduce noise that is non-
directional, for all that it reduces noise picked up off the main lobe,
it increases noise picked up on the main lobe.

Ok, we hear that the noise is not strongly directional. You didn't care
to share how you worked that out. If you had an extremely high noise
level, it would quite likely be local, that is the way of things. It it
appears to not be directional, it is probably very close (ie under the
antenna). It could be in your own home, it could be some kind of fault
with the installation.

If it is within your own home, resolution is somewhat simplified. To
clear away your own home as a source, turn EVERYTHING off and run a
receiver on battery. No prizes for missing something, turn things off at
the main switchboard.

Does the noise vary by hour, day? Is it the same level when all the TVs
and Inverter Air Conditioners should be off.

If the noise is excessive, and it is real local, you have the choice of
dealing with the source, and/or reducing your pickup (eg minimising the
effects of feedline common mode current... good coax, effective
connectors, an effecive balun, system grounding).

Owen