I was not hearing any traffic at all on my scanner for the last couple of hours. I deleted all my frequencies and re-added them I am hearing things now, however, the frequency 852.25000 is nothing but static. Does anyone know what frequency this one is? Thanks!
It's complicated.
Calvert uses a Motorola radio system that does waht is called "trunking". They have a batch of frequencies, one of which is used as the "control channel". When a radio that is part of the system is keyed -- the push to talk button -- the radio generates a series of tones that identify what "talk group" the radio is set for -- police, fire, solid waste, etc. etc. The controller responds with a frequency assignment. The radio then switches to that frequency and transmits the talk group ID tones and then the voice transmission begins. It all happens in a split second. The result is that two transmissions, even on the same talk group ID, may end up being transmitted on different frequencies.
Some scanners know how to decode the control channel, mainly Uniden scanners. These are the "trunk tracker" radios. They will switch to the correct frequency automatically so you can follow a conversation more easily.
For the average person, a "talk group ID" is essentially the same thing as a "channel". The reason the system is designed this way is so there can be many, many "channels" that use only a few PC software and data from reference web sites such a RadioReference.com
I hope I got all this right, because I just use my scanner control and programming software and let it do all the work. Manually programming a modern scanner by pushing teensy little buttons would be... painfull.
To answer your specific question, the frequency with the "static" is probably the control channel frequency. The trunk tracker radios detect this automatically.
- dgates80
