Trunk systems have been used by the phone companies for years. Your home
phone is (most likely) connected by wires from your house to the central
office (CO). Not everyone talks at the same time, so there are less
connections between CO's then there are phones that each one serves. When
you dial a number, the CO assigns you a "pair" (they use fiber-optic) to the
next office and completes the call. When a CO is overloaded, you get the
fast busy signal or the "All circuits are busy" message.

When a radio trunk system user transmits, the trunking computer picks an
unused freq and assigns it to that user (or group).
For example, 50 users 10 frequencies. When the 11th user tries to talk, they
get the busy signal.

Each major company (EDACS, Motorola, EF Johnson, etc) has their own design
for a trunk system, so you can't use a Motorola trunk radio in an EDACS
system.
There are also scanner programming quirks to watch for. Motorola you can
load the frequencies in any order, while EDACS requires they are entered in
a certain order. Any quality site or scanner book wiil have the correct
order.

WC


"Bruce Robertson" wrote in message
.. .
Go to your local Radio Shack.
Ask them if you can hear the local public service on the Pro-95.

If they say yes, Buy it, and have them program it.
If they say no, save your money for a Pro-96.
If they they say they don't know, go to another store.
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Uniden owners please insert comprable model numbers,
____________________________________

Most people won't answer your trunked radio question because
it is something you need to read up on your self from the many resources
avaialable on the web and or else where.

Note: Radio Shack has the police call frequency guide (with the entire
nation on CD) on sale for less the $10. It has an excellent introduction
to
trunked radio etc... in the front matter.