4.811 mHz noise?
 

Janitor Boy Jr wrote:

On Wed, 12 Dec 2007 15:11:54 -0500, JoanD'arcRoast tossed this out for all
to see:

In article UJP7j.3236$1p.2018@trndny01, Janitor Boy Jr
wrote:

On Wed, 12 Dec 2007 01:51:21 -0500, JoanD'arcRoast tossed this out for
all to see:

In article kVi7j.1525$CJ.405@trndny02, Janitor Boy Jr
wrote:

On Mon, 10 Dec 2007 12:43:46 -0500, JoanD'arcRoast tossed this out
for all to see:

Anyone else receiving this? In AM, sounds like a low breathy note
on a flute. In sideband, sounds like a sweeping chirp - once per
second. I'm suspicious, because I can hear it about S3 during the
day, so I'm thinking local. (Perhaps my gas or electric company's
remote read digital meters?)


got the same thing here.
S9+
NE Wisconsin

Thanks. That rules out local.


Back to topic: There's another noisy note from 4.877-4.902. Over S5 at
19:48Z

Weak one from 4.916-4.936. S1 @ 19:58Z

Big one from 4.963-4.995. S5+ @ 20:00Z

WWV is S1 on 5mHz this time of day.

4.734-4.766. S3 @ 20:04Z

Two of them overlap 4.530 S6 @20:06Z

The first one mentioned at 4.810 is an overlap of two, as well. S6 @
20:06Z


I hear it continuously from 4734 right up to 4998~4999 where the splatter
from wwv knocks it out. I hear nothing at all above 5000 though. most of
it is just the one side - "weep". right at 4810 I hear both sides -"weep,
weep". real strong, with near full quieting. it's always there, but the
signal strength changes.

weird.

Kenwood R5000 to a PAR EF-SWL flat out north away from the house.

It's CODAR.

4.811 mHz noise?
 

Janitor Boy Jr wrote:
snip

strange. at 4800, I hear the single "weep" then what sounds like an echo.
4806 through 4810 I hear both "weep, weep" solid. I'll record a few
samples.


A little web research of archives finds mentions of "sweepers" on 4800 +/-
25 kHz of high signal strength in the past five years being an annoyance
across the U.S. and even in New Zealand; consensus amongst respondents
is that they are hf radars for ocean current studies, probably higher
power implementations as opposed to the low power Codar brand systems
documented by the manufacturer at its website. An argument against
OTH radar was that the signals didn't change diurnally or based on
propagation conditions.

Folks with directional antennas could help triangulate these signals; a
little RDF in locations with very strong signals may also be useful.

Michael

4.811 mHz noise?
 

Janitor Boy Jr wrote:
snip


here's a few short clips of what I hear tonight.

http://callgeorge.info/sounds/


Seems to be the same signals as heard from the North Carolina
receiver; I really doubt that 80W codar stations could be
responsible (www.codaros.com) and wonder what sort of
project could justify the power used in these signals.

Regards,

Michael

4.811 mHz noise?
 

In article , msg
wrote:

Janitor Boy Jr wrote:
snip


here's a few short clips of what I hear tonight.

http://callgeorge.info/sounds/

Yes, that's the sounds. I'm glad you were able to post the 4th sample
with the "overlapping" sweeps.



Seems to be the same signals as heard from the North Carolina
receiver; I really doubt that 80W codar stations could be
responsible (www.codaros.com) and wonder what sort of
project could justify the power used in these signals.

....and the apparent bandwidth. What technical application would require
a spectrum sweep like that.


Regards,

Michael

Found another one tonight from 4.522-4.550mHz S5 @ 03:45Z

(actually right at 4.541.60 in usb 6kHz filter, sounds like either an
overlap, or an faint echo? Unlike the 4th recording above, one sweep
goes down frequency; the faint one goes up.)

-j

4.811 mHz noise?
 

Janitor Boy Jr wrote:

On Wed, 12 Dec 2007 19:04:39 -0600, msg tossed this out for all to see:


Janitor Boy Jr wrote:
snip

strange. at 4800, I hear the single "weep" then what sounds like an
echo. 4806 through 4810 I hear both "weep, weep" solid. I'll record a
few samples.


snip

Finally got it here in No. MN at 0310 UTC on 4800 kHz +/- several 100 kHz
at least. 80M amateur band is also open and much quieter than in recent
days.

Michael

4.811 mHz noise?
 

Janitor Boy Jr wrote:

On Wed, 12 Dec 2007 22:23:22 -0600, msg tossed this out for all to see:

snip
snip

Finally got it here in No. MN at 0310 UTC on 4800 kHz +/- several 100 kHz
at least. 80M amateur band is also open and much quieter than in recent
days.



got it pounding in here tonight

http://callgeorge.info/sounds


Not so much here yet tonight, but huge again in NC (online rcvr there).
Unless it was some artifact in the digitizing and transmission over IP,
I heard several instances of "woodpecker" pulses (10 to 15 at about 7pps)
during my listening to the NC receiver last night. That is suggestive
of OTH radar...

I wonder if taking this to some of the Yahoo military and SIGINT sw
groups would get us anywhere.

Michael

4.811 mHz noise?
 

Janitor Boy Jr wrote:

snip


got it pounding in here tonight

http://callgeorge.info/sounds


The sound file 'http://callgeorge.info/sounds/4810AM_12-13-2007_0000UTC.mp3'
sounds a lot like DRM to me (or some similar digital mode with a noise-like
or encrypted spectrum). I'll try decoding it as DRM for a chuckle...

Michael

4.811 mHz noise?
 

msg wrote:

Janitor Boy Jr wrote:

snip


got it pounding in here tonight

http://callgeorge.info/sounds


The sound file
'http://callgeorge.info/sounds/4810AM_12-13-2007_0000UTC.mp3'
sounds a lot like DRM to me (or some similar digital mode with a noise-like
or encrypted spectrum). I'll try decoding it as DRM for a chuckle...


What receiver mode and filter bandwidth did you use to record the
above clip? If it is still there, can you record it at the widest filter
available in AM mode?

Michael

4.811 mHz noise?
 

msg wrote:

I wonder if taking this to some of the Yahoo military and SIGINT sw
groups would get us anywhere.

Or better yet, taking it to the FCC (either directly or via the ARRL)...