Multiple CC's on local Edcacs system

[ve3nsv]

Recently our local 5 site simulcast Edacs system has sprouted a new Control Channel on one of the existing voice channels. The CC doesn't seem to carry any traffic and just manages to hang up all the scanner listeners until that channel is locked out.

Anybody know why the system would have multiple CC's? Is this a sign of bad things to come? It doesn't seem to be affecting the users radios at all.

[Thayne]

Sometimes it is a way to make rebanding or reprograamming less of a hassle.

[ElroyJetson]

Could it be a separate control channel for data services? MDTs, maybe.


Elroy

[greenthumb]

Are you able to run etrunker or Unitrunker on that control channel to see if it's using an out of the ordinary site number? This would tell you if it's possibly what Thayne is speaking about above, although I don't think Canada is rebanding 800 MHz.

It could also be a system related problem that the technicians haven't seen.

[mitaux8030]

This (two control channels in a frequency set) is also used as a method to seamlessly transition from SCAT to a multichannel site, obviously not applicable in your case.

[Prospect62]

Dear God the system is becoming self aware. Run for your life!!!

lol.

[Jay911]

Years ago there was an EDACS system here.. turns out that a handful of the frequencies that people thought were part of the main site/system were actually a smaller, secondary site/system used for backup purposes if the main one went down.

[kf4sek]

We have the same thing happening on one of our sites here in Brevard County, Florida. Two control channels, with different site IDs, at the same time. The frequencies are actually located at the same site and, it is the only site in the county doing this. No surrounding county is running the same frequency that the second control channel is on. What is weird, the second control channel says it is on channel 02 but, the system has no channel 02 in the actual LCN. The actual channel of the second control channel is channel 12, as far as site LCN goes. I have had to delete channel 12 from my scanners in order for them to trunk-track properly. Another weird thing, a couple of weeks ago, the second control channel was on LCN channel 11, saying it was on channel 01. I would think two control channels, of the same type (EDACS 96kbps), on the same system would cause user radios to act up, especially when the site selects a different control channel frequency, as multi-channel EDACS sites do.

[greenthumb]

Whatever is being done in the Brevard County, Florida case is clearly intentional because the failure I am thinking of which could cause that would retain the same site number across both control channels. Reprogramming of the site equipment is required for channels to be new LCNs and have a new site number. They're doing something, but what exactly that is....who knows.

The user radios won't interact with that control channel since they are looking for a specific site number to go along with their pre-programmed control channel list. Once that site number is changed, the radios ignore that control channel even if the radio scans it while looking for a valid CC.

[HarrisRF]

To test simulcast system timing we often patch the CC data to channels in test.

[Unitrunker]

Originally Posted by ve3nsv

Anybody know why the system would have multiple CC's?

The EDACS protocol can support a secondary control channel. I've never actually seen this happen but the control messages to manage this exist. This makes no sense for a small five channel system.

Are you sure it's a control channel? ProVoice and some data formats sound very similar.

[greenthumb]

Do you mean secondary as in an alternate if the control channel fails, or something else?

[Unitrunker]

Originally Posted by greenthumb

Do you mean secondary as in an alternate if the control channel fails, or something else?

Something else (but I don't think that's the case here).