Dear Laurence, LF Group,
The 468kHz frequency does seem to be slated for Chinese Navtex broadcasts -
apparently 424kHz is being used for Japanese language Navtex too. This seems
to coincide with a general shift to using 490kHz for Navtex weather
forecasts instead of "local language" as it was originally supposed to be.
I beleive the international agreements relating to Navtex say that "no more
than 1kW" should be used for Navtex broadcasts, and then only under
exceptional circumstances, in order to minimise mutual QRM. but if you look
at manufacturer's TX offerings, you will struggle to find one less than 1kW.
Fun for DXers, I suppose, but not so clever when you actually need the info!
Several years ago when a 500kHz allocation was first mooted, I spent some
time listening to 500kHz, and most nights used to hear Italian coast
stations - IAR was one I think. They would appear on 500k and tell you to
QSY to some nearby frequency. When you did so they would broadcast a long
list of ships' callsigns, I presume who they had traffic for. But I never
did hear any 2-way operating, and got the impression the whole thing was
computer generated. I haven't heard these coast stations since about 2003,
or maybe before.
Cheers, Jim Moritz
73 de M0BMU
----- Original Message -----
From: "Laurence BY3A-KL1X China" <[email protected]>
To: <[email protected]>
Sent: Saturday, September 19, 2009 9:40 AM
Subject: LF: 500 still in use?
Im asked whether 500kcs or kHz etc is still in use here and yes it is -
heres a TTT TTT Nav warning on 500.00 Khz at Hr +18 from XSV Tianjin radio
about 15 miles from me just a few mins ago.
I dont hear Ship to Ship or Ship to Shore on MF, or should I say I havent
yet and none of my ships or platforms are equipped here, but the Chinese
announced back in 2007 that 486 Khz (assigned) is to be used for a "National
language channel" - Im not sure if this relates to safety traffic/navtex or
gen bsct - or whatever, but Tianjin is just increasing its output power on
that freq to 5Kw, and dont I know it.
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