In Reply to: What is Trunking??? posted by Robby on November 22, 2000 at 19:43:33:
Trunken:
a city buys, say 20 frequencies for all their 200 departments, instead of 200 frequencies. This saves $. Now they need special radios and controlers. every radio has it's own ID and belongs to it's own department. Every radio/department has a priority.
Now, when a police officers keys up he transmits his ID/department. The master control computer 'connects' this officer w/ others in his department on one of the 20 frequencies. then at the same time 2 sewer workers key up and talk on another one of these 20 frequencies... and so on. Because every radio/department has a differnet priority.. conversations can jump around from second to second on anyone of the 20 frequencies as deamed by the control computer. Some low priority conversations may even be cut off mid conversation and be bumped off the bandwidth cuz more important people need to use the frequencies.
The pros of this system is that a city needs to purchase few freqs from the FCC.
the cons of this system is that a city worker may need to wait to get a free channel.
a set of trunk frequnecies can be identified by having one frequency always scream w/ data (known as the data channel) which tells all radios whats available, whats not, who's on the line, talken to who.. blah blah.
The End.