On Wed, 14 Mar 2007 20:29:09 -0700, "Ron Baker, Pluralitas!"
wrote in
:


"Larry Dighera" wrote in message
.. .

Tx Location: Unknown
Station: Unknown
Program:
S4 noise level with two-second S8 transmissions, followed by one
second of no carrier. Modulation method unknown, but there seems
to be a marginally audible low frequency beat in the carrier.
Occasionally the pattern is punctuated with very short pulses of
other pulse-type modulation. Probably some sort of telemetry?
Language: None
Time: 0134U
Frequency: 6,360.0 kHZ
Mode: USB (seems to work best?)
Signal: S8
Readability: ?
SINPO: 35444

Rx Location: Southern California west coast, USA
Equipment: Drake R8B
Antenna: Datong Model IB5 active rotatable dipole
Azimuth: ~160* - ~340* True

It's a maritime ute. Modulation is SITOR.


Ah. Many thanks. I was completely unfamiliar with SITOR. There is a
simple explanation of that mode he

http://en.wikipedia.org/wiki/SITOR
SITOR is used commonly on shortwave bands, where it is used to
transmit maritime-related information such as weather forecasts
and storm warnings. In the United States, it is regularly used by
the United States Coast Guard.

There is also a link to an audio file, so the modulation mode can be
identified.

SITOR has an aurally easy to identify idling pattern.
Synchronization bursts are transmitted every second or so and last
for slightly more than one second. Every few sync bursts, a Morse
identifier of three letters is transmitted (for example NMO in
Honolulu).

However, the wiki audio sample, while similar to that heard on 6360
kHz, seems different. Perhaps that is due to my choice of detector,
but I don't recall hearing any Morse code.

I'll upload both the wiki SITOR audio sample file and the sample of
what I received to alt.binaries.sounds.radio.misc, so you can judge
for yourself.

Globe Wireless, KEJ, Hawaii?
Globe Wireless, KPH, San Francisco?

There is information for those types of stations he

NATIONAL WEATHER SERVICE MARINE PRODUCTS VIA U.S. COAST GUARD HF
SITOR: http://www.weather.gov/om/marine/hfsitor.htm

However, the sound of the sample signal offered he

Click here to listen to what a typical SITOR signal sounds like on
the air: http://www.weather.gov/om/marine/hfsitor.wav

seems to differ from that heard on 6360.0 kHz.

Compare the files I posted in alt.binaries.sounds.radio.misc, and see
what you think.