[600MRG] WD2XSH/20

[Rudy Severns]

Mike (/12) and I tried for a QSO last night and it was really close but no 
cigar.  I could hear his beacon clearly earlier in the evening but I waited 
to long to call him and his signal faded into the noise.  Not clear if the 
noise came up or his signal went down or some of both but we're going to 
give it a shot again this evening.  We'll be on or near 475 kHz and I 
suspect sometime between 0300 and 0400Z his signal will peak if tonight is 
anything like last night.  Of course it may be completely different!   BTW I 
was copying Neil's QRSS3 signal (WG2XSV) loud and clear even though he's 
only emitting mW's!

I'm making progress on my local noise.  The really bad source is probably a 
switching power supply in some kind of electronic equipment although the 
switching frequency seems a bit high.  What I see with Spectran and ARGO is 
a carrier with a wide range of sidebands spaced at exactly 60 Hz.  Clearly 
something is being modulated with raw 60 Hz AC rich in harmonics which gives 
me the raw rasping buzz that wipes out everybody's signal on occasion.  The 
carrier drifts slowly across the band during the day going from about 474 
kHz early on to 478 kHz later in the day.  The signal comes and goes but 
it's there this morning, a Sunday.  The wood products plant doesn't seem to 
be working today so they may not be the source.  While this is a nasty noise 
source it is also a single source which means I have a fighting chance to 
null it out with some rx scheme.  Now I have to fabricate a loop and go find 
out just where this buzz originates.  I've played the game of turning off 
everything in my place (killed the master breaker and went battery powered!) 
but no indication of any effect.  Anyway I'm going to be busy for the next 
couple of weeks fixing working on this so I will only occasionally run WSPR 
or my beacon.  When I have a chance I'll listen for you guys and report but 
in the main I'm going to be pretty quiet until I get this fixed.

One additional comment.  A couple of days ago I mentioned my amplifier, when 
on but not transmitting, was injecting noise into the main antenna which 
then was picked up by the rx antenna.  I wondered why I hadn't noticed this 
before.  It turns out that the local noise completely drowns out the 
amplifier noise except when the local villain is either off or at least has 
drifted well up the band.  The amplifier noise I can fix easily with a relay 
that grounds the transmit antenna while receiving.  The noise is not due to 
fan brushes arcing but is the kind of noise you when a transistor is biased 
on for linear operation.  My amplifier has 55 dB of gain so any small noise 
can be greatly amplified.

73, Rudy