I am having an issue with my scanner always searching for a control channel. Or, Finding Control Channel. I have it programmed the way it is supposed to be, the area I am scanning is in Charlotte NC. It will work great, and then all of a sudden it just drops out. I have no clue in how to fix it or what to even check to fix it. The control channels were put in first, all the scanner frequencies are input and the channels are in there and labeled. The sites are correct. The groups are correct.
BCD325P2/BCD996P2: Control Channels
- Thread starter Jking1103
- Start date
"Finding Control Channel" means you are holding on a talkgroup for a trunked system and the scanner is unable to receive a control channel for the system. This can happen for several reasons.
You have moved out of range for the site
There is something that is blocking/desensitizing the scanner so an incoming signal is not received. Could also be an antenna issue.
The system is using an alternate frequency for the control channel which you do not have programmed.
There could be other things owing to what model scanner you are using.
My first steps would be:
Confirm all frequencies for the closest site are programmed, not just those identified as control channels.
Check antenna connections
Do a weather scan just to confirm the scanner is receiving.
You have moved out of range for the site
There is something that is blocking/desensitizing the scanner so an incoming signal is not received. Could also be an antenna issue.
The system is using an alternate frequency for the control channel which you do not have programmed.
There could be other things owing to what model scanner you are using.
My first steps would be:
Confirm all frequencies for the closest site are programmed, not just those identified as control channels.
Check antenna connections
Do a weather scan just to confirm the scanner is receiving.
If you are seeing signal bars but getting the message, you may be dealing with simulcast distortion in some places.
tvengr
Well Known Member
I agree that you are probably suffering from simulcast distortion. That is a common cause of an intermittent control channel. The Mecklenburg County site on the Charlotte UASI trunked system is simulcast.
| RFSS | Site | Name | County | Freqs | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1 (1) | 001 (1) | Mecklenburg Simulcast | Mecklenburg | 851.2375 | 851.700 | 851.8125 | 852.0875 | 852.2375 | 852.375 | 852.8125 |
| 852.9125c | 853.100 | 853.2625c | 853.350c | 853.8125c | 855.4875 | 855.7375 | ||||
| 855.9875 | 856.2375 | 856.4875 | 856.7375 | 856.9875 | 857.2375 | 857.4875 | ||||
| 857.7625 | 858.9875 | 859.2375 | 859.4875 | 859.9875 | 860.2375 | 860.4875 | ||||
| 860.7625 | 860.9875 |
Please see a good discussion on this at Finding Control Channel
For the newer folks here, Upman is the late Paul Opitz, who was the Uniden product manager.
For the newer folks here, Upman is the late Paul Opitz, who was the Uniden product manager.
tvengr
Well Known Member
Which scanner do you have? The Uniden SDS100 handheld and SDS200 base/mobile are the only scanners specifically designed to receive simulcast sites. Any other scanner may or may not work depending upon your location in relation to the towers.
If the issue is Finding Control Channel, it isn’t simulcast distortion. You gotta be locked in on a channel before distortion can happen.
tvengr
Well Known Member
Not true! The scanner may not be able to detect a control channel at all due to simulcast distortion. If the scanner is unable to decode the control channel due to the out of phase signals, it will not recognize the frequency as a control channel and give the Finding Control Channel message. Simulcast distortion affects control channels also.
Just saying what the Uniden Product Manager said.
Post in thread 'Finding Control Channel'
Finding Control Channel
Post in thread 'Finding Control Channel'
Finding Control Channel
tvengr
Well Known Member
Finding Control Channel = the scanner is unable to detect a control channel on any of the frequencies programmed for that system. This is either because you are out of range of the system or you don't have the correct frequencies programmed.
What Paul said is true but failed to mention that simulcast distortion could prevent detecting a control channel. The thread is from 2016 when P25 simulcast systems weren't as prolific as they are today. The SDS scanners were not introduced until 2019 and were designed specifically to mitigate the effects of simulcast distortion.
What Paul said is true but failed to mention that simulcast distortion could prevent detecting a control channel. The thread is from 2016 when P25 simulcast systems weren't as prolific as they are today. The SDS scanners were not introduced until 2019 and were designed specifically to mitigate the effects of simulcast distortion.
Probably the best thing the OP could do is take the scanner near a site, perhaps 1/4 mile away and see what happens.
Still see finding control channel: programming issue.
Not seeing finding control channel: I learned something new.
Still see finding control channel: programming issue.
Not seeing finding control channel: I learned something new.
tvengr
Well Known Member
I
I agree. My BCD396XT usually shows NFM on my local simulcast system and occasionally the control channel frequency pops up and then goes away again. I cannot get a good lock on the control channel and the audio is all garbled. The Uniden SDS100/200 scanners and the Unication G4/G5 pagers are the only radios that will work at my home location. As long as I have been programming scanners, I still continue to learn something new.
I use a BC325P2 portable scanner. I just purchased another antenna but when I use it I am all over the city being mobile usually. Even sitting still in places it will do it. I have an external antenna but honestly, the cheap included in the box antenna worked better.
Can you try a weather scan to see if the scanner receives?
Are you able to take the scanner close to a site?
Any chance a radio may have been transmitting close to the scanner, or perhaps a static electricity spark happened when touching/connecting the antenna? (That can fry a protecting diode, which unfortunately I have done).
wtp
Member
squelch on 2 ?
for the weather check...
when scanning, hit the hold button, type in 162.4, hit the hold button.
if that one is quiet, try hold, 162.475, hold.
for the weather check...
when scanning, hit the hold button, type in 162.4, hit the hold button.
if that one is quiet, try hold, 162.475, hold.
tvengr
Well Known Member
That is a typical symptom of simulcast distortion. A better antenna increases the number of towers and out of phase signals you receive and degrades control channel decoding. A worse antenna decreases the number of towers and out of phase signals you receive and improves control channel decoding. Try turning on the attenuator. Remove the antenna and replace it with a paperclip. Your scanner will probably work better. When dealing with simulcast distortion, less signal is more.
I've been monitoring the Charlotte-Mecklenburg UASI system for many years. I can tell you from experience, the Uniden SDS scanners are the only scanners that work for me on that system. I bought an SDS 200 about 5 years ago and was amazed at how much I had been missing.
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