Interesting activity on 123.100

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Interesting activity on 123.100

#1 Post by N1RGR » 18 Jun 2014 19:40

Today I had a aircraft directing a marine vessel called Marine-1 as they were tracking a marine animal. I'm guessing it was a whale as they were calling out when the animal surfaced and which direction it was traveling to the surface ship. Interesting I have that freq listed as a simulated guard freq for the 104th fighter wing.
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#2 Post by Maine45 » 18 Jun 2014 21:30

123.100 is actually designated (worldwide, I think) as a search & rescue channel. In the past the Coast Guard used it quite often. However, I have not heard them on it in a number of years. Civil Air Patrol seems lately to be the most frequent user, sometimes when they are serving as simulated target aircraft for the various ANG fighter wings.

I suppose assisting a tangled whale or whatever they were doing might fall under the SAR designation. Would be interesting to know who you heard. NOAA operates several aircraft that may well be involved with marine animal research or rescue. I guess you'll need to hear a callsign!
Southern Maine

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#3 Post by KB1FJR » 19 Jun 2014 09:20

I think 123.100 is also in the survival handhelds which I think are dual band.

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#4 Post by ScanBoston » 19 Jun 2014 10:08

Part 80 Maritime
e. In the 120-156 MHz band the following frequencies are used as indicated: (1) The frequencies 121.500 MHz and 123.100 MHz using A3E emission are available for scene of action search and rescue operations to ship, coast and aircraft stations. Communications in support of search and rescue operations must employ the frequency 121.500 MHz only when communications on 123.100 MHz or other VHF frequencies is not practicable Ship coast and aircraft stations engaged in such communications on 121.500 MHz must shift to 123.100 MHz as soon as possible. (2) The frequency 156.525 MHz is available for intership, ship and coast general purpose, distress and safety DSC calls. (3) The frequency 156.800 MHz is the international radiotelephone distress urgency safety call and reply frequency for ship public and private coast stations. Stations operating on 156.800 MHz must be able to transmit and receive using G3E emission. (4) The frequency 156.450 MHz channel 9 is available for intership ship and coast station general purpose calling by noncommercial vessels such as recreational boats Distress urgency and safety calls should initially be made on 156.800 MHz channel 16 or equipped with DSC on 156.525 MHz channel 70 51 FR 31213 Sept 2 1986 as amended at 52 FR 35245 Sept 18 1987 54 FR 49995 Dec 4 1989 56 FR 9893 Mar 8 1991 57 FR 19552 May 7 1992.

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#5 Post by marylander » 19 Mar 2015 15:17

I also believe that this freq is used nation-wide by Civil Air Patrol for SAR flights
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#6 Post by NIGHTHAWK01 » 19 Mar 2015 18:24

CAP has no authority to utilize 123.10 within its' internal operations. It can only use that channel and other Multicom VHF air channels for coordination with other organizations.
Chicopee, MA

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