What is a "Mutual Aid Radio Channel" Anyhows?

What is a "Mutual Aid Radio Channel" anyhows?

40 or 50 years ago, it was a big deal if a radio had 2, 4, 8, or 16

channels. Nowadays it is common to have 500 channels in a radio.

40 or 50 years ago, it was a big deal if a repeater was used. Nowadays

it is fairly common to have multiple repeaters linked together

(synchronized simulcast).

Mobile (portable) extenders MO3 (vehicle mounted repeaters) are being

used by more and more agencies.

Nowadays - multiple radio channels have been set aside at VHF, UHF,

and 700/800 for interops / mutual aid.

Lets ask a simple question - in light of the previous statements: What

is a modern mutual aid radio channel?

1. A channel that allows coast to coast communications - unit to unit.

In other units, a radio user in Maine can talk directly to a unit in

California.

2. A channel that allows coast to coast communications. This is the

2nd sense of that phrase. Here we mean a radio channel that will be

found in all public safety radios in the USA. If a Maine radio ends up

in California, the Maine radio can talk to any California radios.

3. A channel that allows direct communications to and from the Supreme

Leader from anywhere in the USA.

4. A channel that can be used when the everyday local radio channels

are overloaded or out of service.

A general rule of thumb might be - modern radios have all the normal

everyday radio channels used locally and within adjacent communities.

Some radios might have all of the radio channels used in all adjacent

counties also. Whenever the radio moves out of its home area (maybe 1

or 2 countys), then the radio must switch to nationwide mutual aid

channels - because the radio does not have the capability to operate

on the local channels. (For example, if a San Francisco radio goes to

San Diego or Sacramento or Portland Oregon, the radio cannot function

because it is not programmed to operate on the local talkgroups.) - (A

Boston Police UHF radio cannot operate on New York City Police,

Chicago Police, or Long Beach Police UHF channels - because they are

entirely different channels with entirely different CTCSS.)