Meck Co control channel change?

[jplyler]

It appears the control channel for the main Meck co system has changed. This morning they are using 857.9875.

jon

 

[jplyler]

now it's back on the "normal" freq: 858.4875.

 

[INDY72]

Its normal for Motorola TRS to switch CC's sometimes, and it used to be very common for there to be daily rotation of the usual 4 four cc's. Not to many do it that way anymore, but its still nothing to worry about.

 

[jplyler]

no worries, I just didn't know if that was something they were going to start doing or if it had to do with some type of system test.

Thanks

jon

 

[jeffmulter]

I've seen the CMPD system switch off to 857.9875 on numerous occasions. The RadioReference database also lists 858.2375 and 858.7375 as alternate control channels.

If you setup a scanner for control-channel-only scanning on a Motorola trunked system, the alternates should also be programmed for the system.

Unless a trunked system has a scheduled rotation of control channels, the most-common reason why the control channel switches to an alternate frequency is interference from other systems on the control channel frequency.

When the system controller determines there is interference to the data from the radios on the system, the initial control channel is temporarily placed out-of-service, and the control data is moved to an alternate frequency.

Such events usually (but not always) occur during the overnight hours when the radio signal may be enhanced by atmospheric cooling and inversions.

The overnight can also be an excellent time to monitor for the control channel data of trunked systems you wouldn't normally hear during the daytime.