[Lowfer] WSPR at 630m

[JD]

Just uploaded tonight's spots several minutes ago.  Only four stations 
heard/seen between 2300 and 0400 UTC.  In descending order of signal 
strength, they were XXM, XIQ, XSH/15 and XJM.  Although XSH/15 is only about 
60 miles farther away than XXM and considerably closer than XIQ, and running 
only 4 dB less power, it consistently reported worse SNRr than either, 
sometimes by 15 or 20 dB below XXM.

Wish I'd had a way to run a second receiver and computer tonight, in order 
to do a proper comparison with the one I was testing...a CommRadio CR1a. 
(Also wish the temperature hadn't gotten below freezing so quickly so I 
could have tried for more stations overnight.)  AFAIK it's the first true 
standalone software defined radio for consumer general coverage reception. 
Less flexible than PC dependent radios (no continuously variable IF 
bandwidths, for instance), and lacking some of the goodies of my 
all-hardware radios (like IF shifting, selectable noise blankers, etc) it 
nonetheless looked to be a decent performing and highly portable alternative 
for HF reception when my other radios are tied up doing LF stuff.

So far, that's turning out to be the case.  The past couple of days, I've 
had HiFER results at least as good as my R-5000s give me.  It has been 
significantly more stable with temperature fluctuations thus far, too.  It 
also draws far less power from my marine battery...only about a tenth of 
what my usual radios do.  And, the nice selection of software IF filters 
that came installed in the softare are every bit as steep sided and 
artifact-free as you would want from an SDR

Although the CR1a nominally tunes down to 150 kHz, the maker does not spec 
it for reception below the broadcast band, and for good reason.  At 185.300 
I don't expect ever to see anything but my own signal.  Multitudes of spurs 
fill that whole part of the spectrum, and no amount of preselection helps. 
You don't actually _hear_ anything but the usual faint PLC whine on 185.1 at 
this QTH, but Argo fills up with slightly shaky lines spaced anywhere from 1 
to 1.5 Hz across the whole band.  Nobody makes it through.  Those spurs are 
still visible at 630m, but much less strong, enabling it to be a credible 
performer in that band.  More observations soon, appearing in additional 
detail in an upcoming LOWDOWN.

Antenna was the usual 40 ft mast located 150 feet from a 7.2 kV rural 
electric line that induces 14 VAC at the antenna terminals, buffered with my 
complementary feedback pair buffer amp.

John