Search results
Results From The WOW.Com Content Network
Selective calling features fit into two major categories—individual calling and group calling. Individual calls generally have longer time-constants: it takes more air-time to call an individual radio unit than to call a large group of radios. Selective calling is akin to the use of a lock on a door. A radio with carrier squelch is unlocked ...
In international aviation, SELCAL or SelCal is a selective-calling radio system that can alert an aircraft's crew that a ground radio station wishes to communicate with the aircraft. SELCAL uses a ground-based encoder and radio transmitter to broadcast an audio signal that is picked up by a decoder and radio receiver on an aircraft. The use of ...
Selcall (selective calling) is a type of squelch protocol used in radio communications systems, in which transmissions include a brief burst of sequential audio tones. . Receivers that are set to respond to the transmitted tone sequence will open their squelch, while others will remain
Digital selective calling (DSC) is a standard for transmitting predefined digital messages via the medium-frequency (MF), high-frequency (HF) and very-high-frequency (VHF) maritime radio systems. It is a core part of the Global Maritime Distress Safety System (GMDSS).
Call trace (Malicious caller identification) *60 1160 Call blocking *61 1161 Priority call *62 1162 Selective call waiting *63 1163 Selective call forwarding *65 1165 Calling number delivery activation *66 1166 Continuous redial *67 1167 Calling number delivery blocking 1831 #31# [4] [5] 141 #31# [6] *68 1168 Activate call forwarding on busy ...
Tone squelch, or another form of selective calling, is sometimes used to solve interference problems. Where more than one user is on the same channel (co-channel users), selective calling addresses a subset of all receivers. Instead of turning on the receiver audio for any signal, the audio turns on only in the presence of the correct selective ...
One common type of CCIR selcall used in VHF and UHF FM two-way radio communications, is a 5-tone selective calling system mainly found in some European countries and used by the Swedish Police and the Turkish Police. The tone duration of a 5 tone CCIR selcall is 100 milliseconds (± 10 ms) and the tones are transmitted sequentially.
A more commonly used system is called selective calling or Selcall. This also uses audio tones, but these are not restricted to sub-audio tones and are sent as a short burst in sequence. This also uses audio tones, but these are not restricted to sub-audio tones and are sent as a short burst in sequence.