HFU HF Underground
Loggings => European Pirates and Private Stations => Topic started by: Jock Wilson on June 19, 2019, 2201 UTC
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I have listed particular 'distress' frequencies below for the attention of 'unlicensed AM MODE operators'. Please avoid the use of these frequencies, especially those in bold type.
Your signals might travel up to thousands of miles when long skip conditions prevail, and you could conceivably be preventing a 'distress' call from being received.
So, give the frequencies below a 'berth' of at least 5 kHZ if you are transmitting with 100 watts or less, and 10 kHZ if you are using kilowatts of output power.
The MF/HF DCS distress and calling frequencies are:
2187.5 kHz, 4207.5 kHz, 6312 kHz,
8414.5 kHz, 12577 kHz 16804.5 kHz
Telephony distress traffic is conducted on:
2181 kHz, 3023 kHz, 4125 kHz, 5680 kHz
6215 kHz, 8219 kHz 12290 kHz and 16420 kHz.
The Telex distress traffic uses:
2174.5 kHz, 4177.5 kHz, 6268 kHz,
8376.5 kHz, 12520 kHz and 16695 kHz.
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Indeed. I would note 6215 kHz as pirates seem to like 6210 kHz and 6220 kHz. Since the voice distress frequency is 6215 kHz USB, putting an AM signal on 6220 kHz will cause interference with USB voice comms on 6215 kHz. An AM signal on 6210 kHz (presuming 10 kHz bandwidth) is probably below the bottom edge of 6215 USB, but just barely (an AM signal centered on 6210 kHz with 10 kHz bandwidth would cover 6205 kHz to 6215 kHz, but since 6215 kHz USB is on the upper side of that, it might be okay).
Still, I would avoid using 6210 kHz just to play it safe. I know that 6212 kHz is a popular marine HF-SSB frequency - the 6 MHz marine band starts at 6200 kHz and goes up to 6525 kHz, with SSB voice channels every 3 kHz so 6203 kHz, 6206 kHz, 6209 kHz, 6212 kHz, 6215 kHz, 6218 kHz, 6221 kHz, etc...so parking a big AM signal on 6210 kHz will cause QRM to anybody on 6209 kHz or 6212 kHz.
Avoid 6210-6220 kHz, 6310-6320 kHz, 6265-6275 kHz. The most important ones are the SSB voice distress frequency of 6215 kHz and the DSC distress frequency of 6312 kHz.
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No marine channel plan !
I just heard French fishermen on 6211 USB,
and I remember finding fishermen on .5 kHz frequencies.
And what about the stanag and Russian digital powerful signals, and all sorts of utilities ?
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There's technically an ITU numbered HF SSB marine channel plan (believe it or not). Most marine SSB radios come with these frequencies pre-programmed in them. Fishing fleets will often use whatever frequency they want, including .5 offset frequencies and out of band frequencies.
The data signals and Russian military signals on the marine frequencies are fine, but I don't think they're transmitting on international distress frequencies either. ;)
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There's technically an ITU numbered HF SSB marine channel plan (believe it or not). Most marine SSB radios come with these frequencies pre-programmed in them. Fishing fleets will often use whatever frequency they want, including .5 offset frequencies and out of band frequencies.
The data signals and Russian military signals on the marine frequencies are fine, but I don't think they're transmitting on international distress frequencies either. ;)
Found a Russian digital station on 6215 a few months ago. Signal type identified by ulx2.
It was on 23 April, search for 6215 and utility on this forum.
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Found a Russian digital station on 6215 a few months ago. Signal type identified by ulx2.
It was on 23 April, search for 6215 and utility on this forum.
I don't doubt that. I'm just agreeing with the original poster that using safety of life/distress/emergency frequencies is a bad idea. Transmissions on those frequencies will be noticed by folks who don't want interference on those frequencies. Why risk transmitting on an emergency frequency when there are lots of other frequencies available?
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Found a Russian digital station on 6215 a few months ago. Signal type identified by ulx2.
It was on 23 April, search for 6215 and utility on this forum.
I don't doubt that. I'm just agreeing with the original poster that using safety of life/distress/emergency frequencies is a bad idea. Transmissions on those frequencies will be noticed by folks who don't want interference on those frequencies. Why risk transmitting on an emergency frequency when there are lots of other frequencies available?
At times at the weekend that band can very congested with pirates in Europe. Fortunately most ops know to keep these frequencies clear.
I only know of 2 cases in recent years of pirates being raided for transmitting on distress frequencies. One in the UK a few months ago and a Dutch op some years back.
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If this was such an issue then why was RTE using 6220 KHz some years ago as was Mystery Radio who were jamming out RTE at the time until RTE moved to 6225, again outside the official broadcast bands. Many international broadcasters are using 6200 - 6400 etc, so isn't this guidance out of date?