Stewart Nelson wrote:
If you mean 50 dB above the noise in CW bandwidth or wider, wow!
HBG's power is "only" 20 kW, see
http://www.metas.ch/en/labors/official-time/hgb/tech_d.html ,
so a 200 mW signal would be 50 dB weaker, and likely readable
even with normal CW. Reception would be easy with any sort of QRSS.
Stewart, I should have stated my measurement method when I said "50 db
above the noise". That was from the Argo screen with the receiver in a
400 hz IF BW mode. Pointing to the signal vs a quite spot on the
display. I could clearly hear the pulsed from the 75 kHz signal which I
assume is HBG. It sounds just like 60 kHz WWVB. I have been able to
see the 75 kHz pluses before but this is the first time I could hear the
signal and get Radio Clock to lock up on it. The 73.6 kHz RTTY did stop
which was initially keeping Radio Clock from locking on the time
signal.
Also, is the following about the FSK signals correct?
On about 73.6 kHz is CFH (75 Hz shift and 75 BPS)
and on about 73.3 kHz is Rugby (100 Hz shift and 100 BPS).
Yes the 73.6 kHz signal is 75 Hz shift but I don't know about it rate.
Can I determine this by viewing with Cool Edit? I have a one minuet
.wav file, close to 1 MB, I could send you if you want to analyze it.
I have no problem seeing the 100 Hz shift signal centered on 73.25 kHz
which must be Rugby. That is when the 73.6 blaster isn't running.
Dexter
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