Another multi site p25 Question

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IAmSixNine

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Its possible. Technically your probably not loosing the control channel, rather your getting several and your scanner cant decode them properly so it may appear as signal loss when its actually just not able to decode it properly.
 

tvengr

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Losing the control channel is a classic sign of simulcast issues. You can have a very strong signal, but the scanner is unable to decode it. Above the system quick keys, you should see the control channel frequency when talkgroups are not being received. If it displays NFM, you have lost the control channel. Assuming that the scanner receives properly at times, if you lose the control channel, it is due either to a weak signal or simulcast problems. If you see NFM, the control channel is not detected. With simulcast systems, you have the same control channel data arriving at different times from multiple towers in the site. The scanner is then unable to decode the information. Only the Uniden SDS100/SDS200 scanners and Unication G4 and G5 pagers were designed to deal with simulcast.
 

cg

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Every location with every system is different. Just because a system is simulcast doesn't automatically mean that you will have issues. I have a several simulcast systems I can pickup. Only one I have simulcast issues with because I can receive several of the sites from my location. I have problems with another because of interference. It is a 700/800 MHz system, the 700MHz frequencies are affected but the 800 MHz channels are not. That is not simulcast problems but is broad interference on the 700MHz band that is visible on a SDR spectrum waterfall. I suspect a local Verizon tower or even an issue with the 700 MHz equipment at the transmitter site.
Try moving to a different location in you house, using the scanners attenuator, etc.

chris
 
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Could losing the control channel be a symptom of a multi site simulcast system
Just because a system is simulcast doesn't automatically mean that you will have issues. I have a several simulcast systems I can pickup.
I live in the same state as cg (Not nearby) and own the 325P2.

I don't have any issues at all with simulcast. Some people just like to push the more expensive scanners.
 

GTR8000

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I don't have any issues at all with simulcast. Some people just like to push the more expensive scanners.
While others continually push the false narrative that simulcast distortion is not an actual issue for many people in many locations (especially when mobile), and continue to insist that just because their scanner works fine in their situation, so should everyone else's and that specifically engineered hardware is a waste of money. :rolleyes:
 

ofd8001

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While others continually push the false narrative that simulcast distortion is not an actual issue for many people in many locations (especially when mobile), and continue to insist that just because their scanner works fine in their situation, so should everyone else's and that specifically engineered hardware is a waste of money. :rolleyes:

Them folks don't realize how lucky they are by not having simulcast decode issues. Just because some folks hit the Powerball doesn't mean everyone will hit the Powerball.

Losing the control channel is a classic sign of simulcast issues.

I disagree, respectfully. If you have simulcast issues, you will not lose the control channel, rather, just like all the voice channels, you are getting too much from too many sites.

You might be confusing the normal processing (or as Upman used to say "normal housekeeping") of trunked systems. This happens in both simulcast and non-simulcast trunked systems and is when the scanner is done with listening to the control channel and moving on to something else. I suspect if you were to change the Hold time for the system and thus allowing the scanner to dwell on a site longer, you will see what I mean.
 

cg

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No doubt it is a significant issue for a lot of people. However, when someone already has a scanner that will work on that type of system, they are perhaps better advised to first try to overcome the issue with the existing equipment than spending a lot of money on a new radio.

chris
 
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