[Lowfer] Running ground wave test right now on 74.3213...

[JD]

Here's XRS5 beginning at 1600 and running until just before I returned to 
town.  That was just before Bob started, so if the computer is still 
running, I should now have captures of both.  On my way back now to look.

The significance of this shot is the apparent level difference in Dex's 
signal.  It's not actually a level difference; it's because of noise.

Yesterday I ran "barefoot" as much as possible...no audio clipping.  Today 
I'm doing the opposite.  The racket that drowned everybody out for 5 to 45 
minutes at a time yesterday was already present when I first tuned in this 
morning.  So, I started driving the clipper harder and harder until I could 
see /5 through the noise, and that's where I'll be running today.

As you'll notice, the noise source shut off between the R and the S, and the 
faint "normal QRM" wanderer around 74.3195 suddenly became visible once 
again, too.  I checked on the noise a bit further this time, and found it 
extends from about 71 to about 80 kHz.  It's 30 dB above usual signal+noise 
in my 250 Hz CW bandwidth, so it's a bit of a challenge.

For a while, I was also running an Argo instance in 3 second mode.  I'll 
stitch some of those together and post a link later, for comparison 
purposes.  Without the noise, XRS5 is clear as a bell in QRSS3!  With the 
noise, it's just perceptible at 3 seconds and adequately viewable at QRSS30, 
with the clipper LEDs bright and Argo gain very low.

(Side note: above 80 kHz, the LORAN sidebands were pretty prominent this 
morning.  Wish I had my multicoupler built up from the January LOWDOWN so I 
could run another receiver or two and simultaneously look at VLF and/or some 
NDBs today while checking on 74 kHz.  In the sunny part of the afternoon, 
it'll be warm enough in the building to stay at the bench for a little 
while.  I fully expect there'd be even more improved groundwave as one tunes 
up that direction.)

John 
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