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Scott
Thanks for the information.
Also been running a 2 second 'refresh' spectrum
analyzer display showing the two carriers. Watching for the past couple weeks I
haven't noticed a one or the other carrier situation. The two are always
within a couple dB of each other. Will keep an eye open for that, though.
Easy enough to add another channel...
Sounds like the signal is MUCH stronger at
your location.
GL with ZL.
Jay
---- Original Message -----
Sent: Wednesday, October 05, 2005 10:34
AM
Subject: Re: LF: Re: 135.92 warning
Hey Jay
Care should be taken when measuring the strenght
of that CA station... From
time to time it stops modulation for seemingly
random periods of time and may
idle on either carrier freq, which one?
seems random to me... I include three
plots on my Spec Lab plot to detect
this. Two are measuring the peak in a
narrow BW around each
carrier. The third is measuring the average signal
strenght of the
50Hz BW signal (maybe abit more I can't remember as the plotter
is at
home...) I also look at a spot about 100Hz above and below for the noise
floor measurement of anything less and the noise floor varies with its
signal
strenght... This seems like a good setup for monitoring from
here...
I find the signal is at our noise floor during the day (s0-s1)
and peaks at
night at over +30db over S9 on my rig.
I've noted
correlations between flares and its signal strenght as well...
Back to
trying to work that pesky ZL...
73 Scott
Quoting Jay
Rusgrove <[email protected]>:
>
John & the group
>
> Interesting you should mention this.
I've been plotting NPG the past couple
> weeks ala W3EEE DCF39 style
graph. The signal is quite strong typically
> showing up at 0100Z and
fading out an hour or so after local sunrise. The
> signal is strong
enough that the frequencies between .925 and .975 become
> filled with
'white' on an Argo screen. In order to get to a truly clean noise
>
floor for the noise channel measurement it was necessary to move at least
25
> kHz outside the carriers.
>
> An early sample
before timing issues were sorted out is here:
> http://www.advancedreceiver.com/capture/NPG1.jpg
>
> Had been planning to make this into a 'permanent' upload for
propagation
> study in the next week or so...if there is any interest.
>
> A contact at DOD verified it as Dixon CA running 40
kW.
>
> Jay
>
>
>
----- Original Message -----
> From: John Andrews
> To: [email protected]
> Sent: Wednesday, October 05, 2005 9:32
AM
> Subject: LF: 135.92 warning
>
>
> The area around 135.922 kHz has been used for Europe to
North America
> transmission for several years. In May of
2005, a military TTY station in
> California started using
that part of the band. Following a tip from
> Laurence last
night, I noticed that the signal is quite loud in the
>
eastern
> U.S., and was clearly audible an hour after
sunrise this morning.
>
> They are using 50 Hz shift,
with carriers on 135.925 and 135.975 kHz. I
> don't know
what the keying rate is, but the signal is appropriately wide.
>
> Any of you planning transmissions to North America should
consider moving
> above 136 kHz if this operation continues.
Since the east coast is subject
> to interference from CFH
on 137.00 kHz (+/- a few hundred Hz), there may
> be
>
an upper bound. Mercifully, the CFH operation is intermittent, and
they
> have
> been quiet since mid-summer. With a
number of U.S. and Canadian beacon
> stations running 24/7
in the 137.777 kHz range, it would also be advisable
> to
stay below 137.5 kHz.
>
> John Andrews,
W1TAG/WD2XES
>
>
>
>
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