Community hub
Recent from talks
Knowledge base stats:
Talk channels stats:
Members stats:
Radio silence
In telecommunications, radio silence or emissions control (EMCON) is a status in which all fixed or mobile radio stations in an area are asked to stop transmitting for safety or security reasons.
The term "radio station" may include anything capable of transmitting a radio signal. A single ship, aircraft, or spacecraft, or a group of them, may also maintain radio silence.
The Wilderness Protocol recommends that those stations able to do so should monitor the primary (and secondary, if possible) frequency every three hours starting at 7:00 p.m., local time, for 5 minutes starting at the top of every hour, or even continuously.
The Wilderness Protocol is now included in both the ARRL ARES Field Resources Manual and the ARES Emergency Resources Manual. Per the manual, the protocol is:
The Wilderness protocol (see page 101, August 1995 QST) calls for hams in the wilderness to announce their presence on, and to monitor, the national calling frequencies for five minutes beginning at the top of the hour, every three hours from 7:00 a.m. to 7:00 p.m. while in the back country. A ham in a remote location may be able to relay emergency information through another wilderness ham who has better access to a repeater. National calling frequencies: 52.525, 146.52, 223.50, 446.00, 1294.50 MHz.
Priority transmissions should begin with the LITZ (Long Interval Tone Zero or Long Time Zero) DTMF signal for at least 5 seconds. CQ like calls (to see who is out there) should not take place until after 4 minutes after the hour.
Radio silence can be used in nautical and aeronautical communications to allow faint distress calls to be heard . In the former case, the controlling station can order other stations to stop transmitting with the proword "Seelonce Seelonce Seelonce". (The word uses an approximation of the French pronunciation of the word silence, "See-LAWNCE."). Once the need for radio silence is finished, the controlling station lifts radio silence by the prowords "Seelonce FINI." Disobeying a Seelonce Mayday order constitutes a serious criminal offence in most countries. The aviation equivalent of Seelonce Mayday is the phrase or command "Stop Transmitting - Distress (or Mayday)". "Distress traffic ended" is the phrase used when the emergency is over. Again, disobeying such an order is extremely dangerous and is therefore a criminal offence in most countries.
Up until the procedure was replaced by the Global Maritime Distress and Safety System (August 1, 2013 in the U.S.), maritime radio stations were required to observe radio silence on 500 kHz (radiotelegraph) for the three minutes between 15 and 18 minutes past the top of each hour, and for the three minutes between 45 and 48 minutes past the top of the hour; and were also required to observe radio silence on 2182 kHz (upper-sideband radiotelephony) for the first three minutes of each hour (H+00 to H+03) and for the three minutes following the bottom of the hour (H+30 to H+33).
Hub AI
Radio silence AI simulator
(@Radio silence_simulator)
Radio silence
In telecommunications, radio silence or emissions control (EMCON) is a status in which all fixed or mobile radio stations in an area are asked to stop transmitting for safety or security reasons.
The term "radio station" may include anything capable of transmitting a radio signal. A single ship, aircraft, or spacecraft, or a group of them, may also maintain radio silence.
The Wilderness Protocol recommends that those stations able to do so should monitor the primary (and secondary, if possible) frequency every three hours starting at 7:00 p.m., local time, for 5 minutes starting at the top of every hour, or even continuously.
The Wilderness Protocol is now included in both the ARRL ARES Field Resources Manual and the ARES Emergency Resources Manual. Per the manual, the protocol is:
The Wilderness protocol (see page 101, August 1995 QST) calls for hams in the wilderness to announce their presence on, and to monitor, the national calling frequencies for five minutes beginning at the top of the hour, every three hours from 7:00 a.m. to 7:00 p.m. while in the back country. A ham in a remote location may be able to relay emergency information through another wilderness ham who has better access to a repeater. National calling frequencies: 52.525, 146.52, 223.50, 446.00, 1294.50 MHz.
Priority transmissions should begin with the LITZ (Long Interval Tone Zero or Long Time Zero) DTMF signal for at least 5 seconds. CQ like calls (to see who is out there) should not take place until after 4 minutes after the hour.
Radio silence can be used in nautical and aeronautical communications to allow faint distress calls to be heard . In the former case, the controlling station can order other stations to stop transmitting with the proword "Seelonce Seelonce Seelonce". (The word uses an approximation of the French pronunciation of the word silence, "See-LAWNCE."). Once the need for radio silence is finished, the controlling station lifts radio silence by the prowords "Seelonce FINI." Disobeying a Seelonce Mayday order constitutes a serious criminal offence in most countries. The aviation equivalent of Seelonce Mayday is the phrase or command "Stop Transmitting - Distress (or Mayday)". "Distress traffic ended" is the phrase used when the emergency is over. Again, disobeying such an order is extremely dangerous and is therefore a criminal offence in most countries.
Up until the procedure was replaced by the Global Maritime Distress and Safety System (August 1, 2013 in the U.S.), maritime radio stations were required to observe radio silence on 500 kHz (radiotelegraph) for the three minutes between 15 and 18 minutes past the top of each hour, and for the three minutes between 45 and 48 minutes past the top of the hour; and were also required to observe radio silence on 2182 kHz (upper-sideband radiotelephony) for the first three minutes of each hour (H+00 to H+03) and for the three minutes following the bottom of the hour (H+30 to H+33).