Emergency and call channel

In the radio service, the emergency and call channel is the radio frequency on which radio stations first contact each other in order to then agree on a different frequency - the working channel - for further traffic processing ( call channel ). This frequency is usually also used for emergency traffic ( emergency channel , emergency frequency ).

Marine radio

In marine radio , the frequency ranges of the emergency and call channels are as follows:

Emergency and call channels according to marine radio frequency bands

Area		Frequency range	Emergency / call frequency	DSC - frequency	Remarks
Medium wave (MW)		415-526.5 kHz	500 kHz		Touch radio, obsolete in Europe
Limit wave (GW)		1605 - 3800 kHz	2182 kHz	2187.5 kHz
Short wave (KW)	HF 04	4000 - 4438 kHz	4125 kHz	4207.5 kHz
	HF 06	6200 - 6525 kHz	6215 kHz	6312.0 kHz
	HF 08	8100 - 8815 kHz	8291 kHz	8414.5 kHz
	HF 12	12230-13200 kHz	12290 kHz	12577.0 kHz
	HF 16	16360-17410 kHz	16420 kHz	16804.5 kHz
Ultra short wave (VHF)		156-162 MHz	156.8 MHz (channel 16)	156.525 MHz (channel 70)

Aeronautical radio

In aviation radio , the frequency 121.5 MHz is internationally reserved for civil emergency traffic, in the military sector the 243.0 MHz is used. In rare cases, these are also used as a call frequency: If a civilian aircraft is approached by a military one and requested to make contact, the following radio communication is processed via one of the emergency frequencies. However, there is no general call frequency in aeronautical radio: Ground stations are called using the frequency published in the aviation manual, the frequency 122.8 MHz is available for on-board communication.

BOS radio

The general emergency call channel for an emergency call in the analogue German BOS radio is channel 444 two-way communication / sub-band (76.155 / 85.955 MHz). Depending on the local control center, activation takes place by means of ringer 1 or 2.

If you do not know the local canal (for example, when traveling in a convoy or during interregional operations, e.g. during flood operations), an emergency call can be made via this canal. As a rule, he then runs into a police station that reports directly to the Ministry of the Interior.

In the German BOS digital radio, there is an emergency call button on every terminal which, when pressed, transmits the alarm and the location (GPS data) to the responsible operations center or control center.

The BOS digital radio also has the function of calling for help, which, when actuated, communicates to the nearest operations center or control center (location-based routing).

Rega Funk

The Swiss Rega operates its own VHF radio network nationwide . The 161.300 MHz frequency is used nationwide as an emergency call channel, which is monitored by Rega's control center in Zurich. The ZVEI-1 selective call procedure is used to alarm, whereby the call sequence 21414 is used for alarming. The call sequence 21301 can be used to check whether a connection is possible. The 161.300 MHz frequency can be used by anyone in Switzerland without an OFCOM license . Corresponding VHF handheld radios with 2.5 watt output power are freely available in Switzerland without a radio license. A helicopter can be instructed using this frequency, as Rega's helicopters can also communicate using this frequency. Rega also listens on the 159.200 MHz frequency, which is also used to alert helicopters. This frequency is only available to mountain rescue services and mountain hut emergency call stations. The call sequence 21414 is also used on this frequency to alert the headquarters in Zurich. The frequency is used to alert Rega helicopters, especially in southern Germany.

Individual evidence

1. ↑ FREQUENCY PLAN according to § 54 TKG on the division of the frequency range from 0 kHz to 3000 GHz to the frequency usages as well as the specifications for these frequency usages. (pdf) Federal Network Agency , October 2019, accessed on January 27, 2020 . 
2. ↑ Recommendation ITU-R M.541-10 Operational procedures for the use of digital selective calling equipment in the maritime mobile service. (pdf) Annex 6 Frequencies used for digital selective calling. ITU-R , October 2015, accessed January 28, 2020 . 
3. ↑ ^{a b} International Civil Aviation Organization : Aeronautical Telecommunications (Annex 10 to the Convention on International Civil Aviation) - Volume V: Aeronautical Radio Frequency Spectrum Utilization , Second Edition, July 2001, available online (PDF) , accessed on June 11, 2017
4. ↑ AOPA Letter 4/2005, p. 25, available online (PDF) , accessed on October 19, 2011
5. ↑ www.funkcom.ch radio network REGA
6. ↑ www.rega.ch Information sheet on emergency radio