[ADXA] noise chasing

[Dennis Schaefer]

Randy, W5ZJ, has given me some good advice about Pennant antennas and even
sent me some ferrite binocular cores for matching transformers.  I'm in the
process of figuring out how to orient the trial Pennant.  I thought my
noise sources were mainly from N to E but weather kept me from getting out
and doing much snooping.

I rotated the yagis and then went out today with an FT-817 (handheld HF
rig) and a 20M antenna.  I walked all around listening on 20 with good
sensitivity and 80 with poor sensitivity because of the 20M antenna.  I
verified what I was seeing on my yagis - the main noise source is to the
South.  There is a house back there, about 700 feet away.   The poles and
transformers to the N and E are quiet.  I didn't walk right up to the
houses they are associated with, but those seem quiet also.

The noise to the S has that raspy, pulsing noise I usually associate with
power line noise or some kind of arc.  I know the noise is strong on HF and
6M but I'm limited on checking on 80 and 160.  I could attach something to
the FT-817 that would be better on 80 but I think the source to the South
is a broadband noise signal.

The other hot spot is my electric meter, but I only detect noise when the
817's antenna is within a few inches.

I also have a TinySA spectrum analyzer, which is a truly remarkable
instrument for the size and price, but it doesn't seem to be sensitive
enough for outside checking.  I can hold it up to a computer or router or
wall wart and see the spurious emissions clearly but this is with the
little antenna just inches away.  I haven't begun to analyze things
associated with my house yet, but I will get to that.  I have a lot of
FT-240-31's and I'm sure some will be needed.

My inclination now is to put the Pennant with its null to the South.  It
should cover EU and AS that way and I could get an idea how it works.  I
may try to make it reversible but I want to keep it simple for now.

73,
Dennis/RZ
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