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chirps or sweepers around 4800 kHz reprised

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msg

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Dec 25, 2007, 9:21:35 PM12/25/07
to
Has anyone made any progress investigating the persistent chirp
or sweep signal heard around 4800 kHz and elsewhere? It is
about S2 to S3 here in No. MN tonight and S9+/-20db in NC/USA
as heard on an internet receiver there.

Michael

Mike

unread,
Dec 25, 2007, 10:13:20 PM12/25/07
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It's CODAR. Radar applications used to measure coastal currents. See
the following URL:

http://www.thecoolroom.org/instruments/instrument_codar.htm

Merry Christmas,

Mike

msg

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Dec 25, 2007, 10:33:00 PM12/25/07
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Mike,

Thanks for your reply.


> It's CODAR. Radar applications used to measure coastal currents. See
> the following URL:
>
> http://www.thecoolroom.org/instruments/instrument_codar.htm
>

In a previous thread, the CODAR speculation was discussed, but due
to the extremely powerful signals, heard across the U.S., it was
felt that this was a less than well-disclosed emission. CODAR
is according to various sites describing existing systems, low
power. Quoting from the site you referenced above:

" Each remote site contains two antennas and a small 6'x 8' shed.
One antenna (left) transmits a radio wave out across the ocean
surface. The power of this transmitted signal is only 40 watts."

Any amateur doing QRP would envy the punch of this signal at only 40w
if this is truly the source ;-)

Other listeners to the signal around 4800kHz have claimed to hear
various associated signals, mode changes, and other strange
activity. One speculation is a test of OTH radar and a possible
association with Naval exercises (foreign services).

Ergo, has anyone learned anything more definitive about this?

Regards,

Michael


Telamon

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Dec 25, 2007, 10:41:19 PM12/25/07
to
In article <13n3ebj...@corp.supernews.com>,
msg <msg@_cybertheque.org_> wrote:

These sweeps are a form of low resolution radar used to measure wave
heights, ocean currents (sea surface conditions) and are used on several
HF frequency bands although I have not heard of that low a band used.

Maybe you are getting an image.

Just do a Google search on CODAR. You will get a lot of hits.

--
Telamon
Ventura, California

Message has been deleted

Barnard Peters

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Dec 26, 2007, 2:21:36 AM12/26/07
to
On Tue, 25 Dec 2007 21:33:00 -0600, msg wrote:

> Mike,
>
> Thanks for your reply.
>> It's CODAR. Radar applications used to measure coastal currents. See the
>> following URL:
>>
>> http://www.thecoolroom.org/instruments/instrument_codar.htm
>>
> In a previous thread, the CODAR speculation was discussed, but due to the
> extremely powerful signals, heard across the U.S., it was felt that this
> was a less than well-disclosed emission. CODAR is according to various
> sites describing existing systems, low power. Quoting from the site you
> referenced above:
>
> " Each remote site contains two antennas and a small 6'x 8' shed.
> One antenna (left) transmits a radio wave out across the ocean surface.
> The power of this transmitted signal is only 40 watts."
>
> Any amateur doing QRP would envy the punch of this signal at only 40w if
> this is truly the source ;-)

I've had the initial researchers who developed CODAR confirm this signal
years ago. They could not believe the propagation as I was over 1000miles
from the test site. Unfortunately, now that it's in full commercial
deployment, there seems to be hundreds of sites on several bands. Highest
I've heard has been 19Mhz.

I've tried to file a complaint with the FCC but unfortunately there are
no legal avenues as it has been approved by the FCC. Perhaps the ITU can
take complaints as this signal seems to block international broadcast?

It would not be so bad if these things would ID at the top of the hour so
at least propagation could be tracked.

JoanD'arcRoast

unread,
Dec 26, 2007, 2:16:20 PM12/26/07
to
In article <pan.2007.12.26.07.21.35.415592@blueplanet>, Barnard Peters
<o...@two.com> wrote:

Absolutely *stunning* signals for 40 watts :-)

Do I smell governmental dissemblance?

-j

Telamon

unread,
Dec 26, 2007, 3:21:28 PM12/26/07
to
In article <pan.2007.12.26.07.21.35.415592@blueplanet>,
Barnard Peters <o...@two.com> wrote:

I don't understand how they get away with broadcasting in the SWBC
bands. Someone on the west coast has been ruining the top of the 25
meter band and the low end of the 22 meter band for years now. I guess
it's time to start complaining.

--
Telamon
Ventura, California

Telamon

unread,
Dec 26, 2007, 3:23:27 PM12/26/07
to
In article <261220071416205625%JoanD'arcR...@biteme.org>,

I think most of this activity is University research.

--
Telamon
Ventura, California

msg

unread,
Dec 27, 2007, 12:11:03 PM12/27/07
to
Barnard Peters wrote:

> On Tue, 25 Dec 2007 21:33:00 -0600, msg wrote:

<snip>

>> The power of this transmitted signal is only 40 watts."
>>
>>Any amateur doing QRP would envy the punch of this signal at only 40w if
>>this is truly the source ;-)
>
>
> I've had the initial researchers who developed CODAR confirm this signal
> years ago. They could not believe the propagation as I was over 1000miles
> from the test site. Unfortunately, now that it's in full commercial
> deployment, there seems to be hundreds of sites on several bands. Highest
> I've heard has been 19Mhz.
>
> I've tried to file a complaint with the FCC but unfortunately there are
> no legal avenues as it has been approved by the FCC. Perhaps the ITU can
> take complaints as this signal seems to block international broadcast?
>
> It would not be so bad if these things would ID at the top of the hour so
> at least propagation could be tracked.

Indeed, most every other non-covert automated radiator on LF/HF/VHF is
required to ID so why not these? It appears that the commercial systems
employ software control of the RF sections (probably not SDR however) so
it would probably not require hardware retrofits to add ID. How about an
online petition with verifiable signatures sent to members of congress
involved in oversight?

Regards,

Michael

RHF

unread,
Dec 27, 2007, 6:31:48 PM12/27/07
to
On Dec 25, 6:21 pm, msg <msg@_cybertheque.org_> wrote:
> Has anyone made any progress investigating the persistent chirp
> or sweep signal heard around4800kHz and elsewhere? It is

> about S2 to S3 here in No. MN tonight and S9+/-20db in NC/USA
> as heard on an internet receiver there.
>
> Michael

? CoDar Like Sounds on 4800 kHz ?

I have it here centered around 4800 kHz [4775 kHz ~ 4825 kHz]
with Signal Levels of S7 peaking at S9.

So How Does All That CODAR Stuff Work ?
http://www.thecoolroom.org/instruments/instrument_codar.htm
http://www.cds.caltech.edu/~shawn/LCS-tutorial/oceancurrents.html
* Sounds Heard on 4800 kHz

4800 CODAR "Swisher" a CODAR Transmitter from somewhere
along the Southern California Coast.
http://mt-shortwave.blogspot.com/2006/11/blog-logs-mexico-dxpedition.html
-source- Shortwave Central Blog {Monitoring Times}

RHF's Alternate Theory - Then again they could be using
it to CoDar Sweep the Lakes {Lochs} for 'Nessies'
http://en.wikipedia.org/wiki/Loch_Ness_Monster
* New Melones Lake & Dam
http://en.wikipedia.org/wiki/New_Melones_Dam
* Lake Don Pedro & Dam
http://en.wikipedia.org/wiki/Lake_Don_Pedro

~ RHF
RHF's Radio Shack in Twain Harte, California -USA-
http://en.wikipedia.org/wiki/Twain_Harte%2C_CA
Shortwave Radio / Receiver and SWL Antenna Info
SHACK INFO => http://tinyurl.com/2skmxm
.

Barnard Peters

unread,
Dec 28, 2007, 12:43:51 AM12/28/07
to
On Wed, 26 Dec 2007 14:16:20 -0500, JoanD'arcRoast wrote:

> In article <pan.2007.12.26.07.21.35.415592@blueplanet>, Barnard Peters
> <o...@two.com> wrote:
>
>> On Tue, 25 Dec 2007 21:33:00 -0600, msg wrote:
>>
>> > Mike,
>> >
>> > Thanks for your reply.

<snip>


>> It would not be so bad if these things would ID at the top of the hour
>> so at least propagation could be tracked.
>
> Absolutely *stunning* signals for 40 watts :-)
>
> Do I smell governmental dissemblance?

Personally, I think the republicans are trying to block any form of
communications they can't control. Thats why we have codar, BPL and the
military demanding wide band HF access. Commies! ;-)))

(ducking)

Mark Zenier

unread,
Dec 27, 2007, 1:47:27 PM12/27/07
to
In article <telamon_spamshield-9...@newsclstr03.news.prodigy.net>,

On a Google search a few years back for 'Over the Horizon Radar",
I found pages on a Raytheon web site for a system they were selling.
It was developed and used in Canada for coastline surveillance. Claimed
to be able to detect a Jet ski from [mumble] miles away. Transportable
in a couple of vans, and ran (as I remember) 10 kW. It was higher in
frequency, though, I think it ran 18-30 MHz.

Mark Zenier mze...@eskimo.com
Googleproofaddress(account:mzenier provider:eskimo domain:com)

RHF

unread,
Dec 30, 2007, 6:28:03 AM12/30/07
to
> (ducking)- Hide quoted text -
>
> - Show quoted text -

Nah - It's Gobermet Mind Control !

It's Time to put-on the AFDBs
http://zapatopi.net/afdb/

They're Coming To Take Me Away Ha-Ha !
http://www.youtube.com/watch?v=XbJ1zEgR7g8

there now i feel better ~ RHF
.

RHF

unread,
Dec 30, 2007, 6:38:35 AM12/30/07
to
On Dec 27, 3:31 pm, RHF <rhf-newsgro...@pacbell.net> wrote:
> On Dec 25, 6:21 pm, msg <msg@_cybertheque.org_> wrote:
>
> > Has anyone made any progress investigating the persistent chirp
> > or sweep signal heard around4800kHz and elsewhere? It is
> > about S2 to S3 here in No. MN tonight and S9+/-20db in NC/USA
> > as heard on an internet receiver there.
>
> > Michael
>
> ? CoDar Like Sounds on 4800 kHz ?
>
> I have it here centered around 4800 kHz [4775 kHz ~ 4825 kHz]
> with Signal Levels of S7 peaking at S9.
>
> So How Does All That CODAR Stuff Work ?
> http://www.thecoolroom.org/instruments/instrument_codar.htm
> http://www.cds.caltech.edu/~shawn/LCS-tutorial/oceancurrents.html
> * Sounds Heard on 4800 kHz
>
> 4800 CODAR "Swisher" a CODAR Transmitter from somewhere
> along the Southern California Coast.
> http://mt-shortwave.blogspot.com/2006/11/blog-logs-mexico-dxpedition....

> -source- Shortwave Central Blog {Monitoring Times}
>
> RHF's Alternate Theory - Then again they could be using
> it to CoDar Sweep the Lakes {Lochs} for 'Nessies'
> http://en.wikipedia.org/wiki/Loch_Ness_Monster
> * New Melones Lake & Dam
> http://en.wikipedia.org/wiki/New_Melones_Dam
> * Lake Don Pedro & Dam
> http://en.wikipedia.org/wiki/Lake_Don_Pedro
>
> ~ RHF
> RHF's Radio Shack in Twain Harte, California -USA-
> http://en.wikipedia.org/wiki/Twain_Harte%2C_CA
> Shortwave Radio / Receiver and SWL Antenna Info
> SHACK INFO =>http://tinyurl.com/2skmxm
>  .

Now Hearing the Same Sweeping "CoDar" Like Sounds on :
4800 kHz; 4430 kHz 4660 kHz and 5205 kHz. @ 11:30 UTC
- - - Strongest near 4800 kHz

Earlier today @ 1:30 UTC - I heard it on 4545 kHz; 4565 kHz;
4400 kHz; 4430 kHz; 4800 kHz and 5190 kHz
- - - Strongest near 4430 kHz

~ RHF
.

Flyguy

unread,
Jan 5, 2008, 3:22:26 AM1/5/08
to

The federal government (FCC) knows that SWL's have no clout on this
subject. That's why they chose some of the international HF broadcast
bands for the CODAR project. It's considered to be a national safety
issue and will therefore continue to disrupt our shortwave listening for
the sake of monitoring storms at sea. IOW- There is nothing we can do
about it. I tried too.
BTW- The 60-m tropical band was the first to be used for the CODAR
service. Now it extends to several other higher bands.

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