On 28 Apr 2014 at 18:25, Don Moman VE6JY wrote:
> Just in the last few minutes I have logged into remote Perseus receivers
> near Vancouver and Seattle and the spectrum in and around 4286khz is
> normal with no indication of any wide band noise.
I may have miscommunicated: I and others in this area, are hearing very
high levels of "white noise" in the ham bands, and we have all determined
that it began about a year ago.
Two days ago, I tuned up from 3576 Khz TO 4286 KHz. As I tuned up, the
"white noise" level slowly kept rising until I hit 4286 KHz where the signal
peaked at 25db over S-9. Continuing to tune up from 4286 KHz, the "white
noise" level fell slowly until it is "only" S-8 on 20 meters.
>From this I concluded that the source of what I, and others, are hearing as
"white noise" IN THE HAM BANDS, is that STANAG signal on 4286 KHz....at
least here in Moscow, Idaho.
> The sound of Stanag 4285 has a harsh repetitive sound that I sure would not
> call
> white noise.
I agree. It is not white noise on 4286. It is the very harsh repetitive noise
you
describe. On USB, on 4285.5 Khz one can hear what I would call
"interleaving" of something. Data perhaps.
It is ONLY in the HAM BANDS that I and others are hearing "white noise",
NOT on 4286 Khz.
At this point, I believe it is really terrible distortion of the STANAG signal
causing really terrible side-band interference.
As I mentioned earlier, if it IS this STANAG signal, it is probably due to a
misadjusted transmitter or antenna system.
> I don't know what you and others are hearing (I am curious too)
I can send you recordings of it. I have both narrow-band versions (less than
1KB file size) and wide-band versions (at least 5 MB files sizes). If you would
like to hear it. I have recorded what I am hearing on the ham bands,
specifically 3576 Khz, and on 4286 Khz, both in AM mode at 6 KHz
bandwidth and in USB.
The "motor" sound associated with STANAG is quite apparent on the 3576
Khz AM recording.
All recordings are about 30 seconds long.
> I don't think this is related but will mention it in case someone has
> noticed this too....
>
> Much of this winter/spring I have observed a fast pulsating sounding
> sweeping signal (somewhat like the Chinese OTHR on 40m) on the lower end of
> 80m
> in our evenings. It can be on for several minutes and then off for what I
> would
> call irregular times - no on/off pattern that is obvious to me. It starts
> below
> 80m and comes up to maybe 3750, the edges aren't well defined and it isn't
> that
> strong here. Using the 80m 4 sq the signal peaks to my SW. It has been heard
> by others in southern Alberta and Northern BC (many hundreds of km distant) at
> the same times so it certainly isn't too local.
I am hearing something like that too on or about those same frequencies.
Sometimes it is so loud as to drown on all but local signals.
> On rare days I have also noted it on 160m in the 1900 khz area.
I have not been on 160 for a while and have not checked for it there.
Ken W7EKB
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