[GreenKeys] Strange RTTY Signal on 29.684

[Geoff Fors]

I am a bit behind on replying to some of the messages about this topic.

I'm about 150 miles up the coast from Vandenburg AFB, in Monterey. Unless
the signal is
extremely high power I don't think it would make it up here.  The consensus
among the locals is that the signal is from the north of us, i.e. San
Francisco Bay area, which encompasses a lot of terrain including quite a few
military installations.  I am working on getting reports from up in that
area to see if the signal can be heard there.

I agree that upon further listening this signal is technically not Baudot
RTTY but actually FSK data with a narrow shift.  I will hook up the DES
M-7000 and see if I can
determine the baud rate and shift.

I checked lower frequencies (i.e. divide by 2, 3, etc.) to see if this was a
harmonic, but they are all clear.

In my case, I determined the frequency by the lazy and simple method of just
tuning for zero beat.  For all intents and purposes 29.684 is accurate
enough to say where it is.  The receiver is an R-1051B/URR slaved to a
URQ-10 frequency standard.

Regarding Peter's comment, you are right, there isn't much to copy on HF as
far as commercial RTTY these days, other than something like the French
South Pacific naval station FUF's marker broadcast (which switches to
encrypted when they actually send something.)  I tried to read some Russian
shipping RTTY using third-shift Cyrillic decoding but that ended in
frustration as well.  There's always the new weekend KSM RTTY broadcasts
brought to us by the brave folks at Radiomarine.org.

Geoff
WB6NVH