Command Frequencies

[dkcheatum]

Do I only need to use the Command Frequencies or do I also need to program the sub-frequencies. Thanks

 

[RaleighGuy]

By command frequencies do you mean control channels on a trunked system? By sub frequencies do you mean voice channels? Also, if you do mean that, the answer is different depending on your scanner, so please share that with us. It also helps to know which system you are asking about.

 

[dkcheatum]

It's a trunked P25 system, and I using a Uniden BCD396 scanner. The sheet I downloaded from RR shows System Frequencies with a "C" after two of them for Command and the rest with an "A", which is alternate control channels. I didn't label this correctly in my original question. Do I need to program the Alternate Control Channels? Thanks

 

[Whiskey3JMC]

Do I need to program the Alternate Control Channels? Thanks

Yes. Control channels rotate on P25 systems. Program them all

 

[DJ11DLN]

Yes, regular and alternate control channels. You don't need to program the other site frequencies, just the talkgroups. The scanner will automatically tune to the active frequency for the talkgroups you have programmed via info from the control channel datastream.

 

[natedawg1604]

Yes. Control channels rotate on P25 systems. Program them all

At least in my state, the (many) Motorola systems we have do not rotate control channels, only the Harris systems do this.

 

[ofd8001]

At least in my state, the (many) Motorola systems we have do not rotate control channels, only the Harris systems do this.

Same here - the primary control channel is always used unless something goes wrong with it and an alternate is used. I can count on one hand how often this has happened. Fortunately I had the alternates programmed.

 

[DJ11DLN]

Same here - the primary control channel is always used unless something goes wrong with it and an alternate is used. I can count on one hand how often this has happened. Fortunately I had the alternates programmed.

Same here, I have the alts too but almost never see them in use. Just there to keep the site running in case the circuits running the primary go ker-plunk. Also a Moto system (Safe-T).

 

[CanesFan95]

I thought the letter 'c' simply meant control channel. And remember, the info on RR is only as good as what people submit.

 

[ecps92]

Altho they may not rotate, the radios are generally programmed [atleast most "M"] with atleast one Alternate CC, in-case of a failure or interference to the primary CC

At least in my state, the (many) Motorola systems we have do not rotate control channels, only the Harris systems do this.