[Lowfer] MP, XKO and possibly VO1NA into 7-land

[Clint Turner]

I'm getting MP, XKO and a (possible) VO1NA into the Salt Lake area this 
evening - see attached, this having been grabbed on 30 December, 2013 at 
0512Z.  By 0540 MP had taken a fairly deep fade and all sight of VO1NA 
had pretty much been lost.

There has been some QSB as can be seen from the attached.  The signal 
from (possible) VO1NA never seems to quite manage to stay out of the 
noise for very long, but XKO has occasionally been strong enough to be 
audible in the speaker.

In looking up/down from the watering hole within the FFT range, I don't 
see anyone else that look, but in an earlier capture I noted that there 
seems to have been a signal around 776.8-777.0 and then at approximately 
0115z it jumped to approximately 778.0, abruptly disappearing at about 
0245:  Unfortunately, I had the scroll rate on Spectrum Lab running too 
slow and could not decipher the keying. Anyone guess as to who that 
might have been?

* * *

For the receiver, I'm using and RFSpace SDR-14 coupled to my my 26 year+ 
old LF-400B E-field whip via my synchronous noise blanker - which also 
provides power.  Fortunately, the blanker wasn't needed tonight.  It's 
surprisingly hard to get the SDR-14 to stay put for some reason:  It 
doesn't really drift that much, but when people apologize for their 
grabbers being 0.2 Hz off, it can sometimes be miles away!

* * *

In the past night or two I've been trying to get some captures, but I 
noticed that things didn't sound "right":  I could hear the normal VLF 
OK... sort of... but WWVB didn't register as any more than 10-over on my 
old TR-7.  Today I braved the ice on my metal roof (it wasn't really 
that bad) and pulled the LF-400B and found that 2 of the 3 10mH lowpass 
inductors on its front end hand gone bad:  One was open, and the other 
had 3-5 times the normal DC resistance. Inspecting them, it looks as 
though the potted epoxy portion of the coil has shrunk slightly and is 
starting to break away from the case and likely this has done something 
bad to the windings within!

I didn't have any of the same kind of type of 10mH chokes on hand (they 
are now on my "Mouser-Key" list...) but I did have some of the same 
manufacturer of 27mH so I put those in there:  It's now pretty deaf by 
the time I get to 500 kHz (but still sort of usable...) but it hears as 
well as it ever did in the VLF and the lower LF range. It's been up in 
the air almost continuously since 1986 or so, so I don't feel too bad 
about having to replace a part now and then!

A foot or so below the E-field whip - which is mounted on a 5' metal 
pole attached to a vent pipe - the RG-58 coax is wound 2-3 layers deep 
around a large AM-BCB ferrite:  The BNC on the LF-400B itself is 
grounded to the metal roof (using the same grounding point as my MedFER 
beacon - which is off at the moment) and this helps keep much of the AC 
mains QRM out of the system.  Just inside the shack the shield of the 
coax is grounded to a buried (and abandoned) CATV run and the ham 
shack's ground field just outside the basement window. About 40' of the 
RG-58 is coiled and the end of that coil is wrapped around a salvaged TV 
flyback core to provide several mH of common-mode choking.  The result 
of this is that only the most obnoxious things in the house (light 
dimmer in the shack, etc.) appear on the receiver.

I'll steer this thing over to 187 and see if I can see anything from 
JAM... Who knows.

73,

Clint
KA7OEI

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