Very frustrating problem with one 536HP

[AA6IO]

I don't know where to go with this problem, so I posting on a new thread. I have two 536HPs with exactly the same profiles and favorite lists. Both seem to working the same on all conventional and trunk sites except on noteable exception.
On my Los Angeles Trunking Favorite List, I have the LA ICIS P25 system as system 2 (identical on both units), am monitoring the Pasadena Site. All settings, frequencies for control sites, everthing is identical.
However, on one 536HP get 4 bars and DAT indicator, and picking up TGs On the other, getting no bars, indicator shows DAT very intermittent, and picking up no TGs. Same antenna with MCA204M coupler.
Everyother trunk system on this Favorite list 2 (I have 10 of them) is working identically the same between both scanners. It is only this one trunk site that is behaving differently. Yesterday, everything was fine, exactly the same. Today, I noticed had no hits on logging on the one scanner in question for LA ICIS P25.
I even copied the system in question into Sentinel, loaded it into other scanner, and works fine.
I have been trying to figure out what the heck is going on for the last couple of hours. Have absolutely no idea. Location control is off on both, all service types are on for both. Have no idea. Please help.
Wonder if anyone has some thoughts.

Steve AA6IO

 

[JamesO]

Sounds like a basic antenna/cable/connector issue??

Not sure what you are using for an antenna, I would swap the antennas/feed coax and see what happens.

The other possible issue is global attenuation has been enabled on the problem scanner?

 

[AA6IO]

JamesO
Thanks for your reply. However, after several hours I found what the problem was. I had squelch setting on both scanners at about 5 to 6 for this system. Can actually go all the way to squelch level 15 or more and they normally come in fine.
On other scanners, once I have set the squelch for a trunk system, I never really had to set it again.
It all of a sudden dawned on me to try and adjust the squelch down a bit on the problem scanner with this particular P25 system. Went to 5, 4, 3, 2, 1 and still the same. Then went to squelch 0, and all of a sudden the problem scanner locked on the control channel and everything all right. Then could turn the squelch up to 5, 10, and even 15 with no problem
This was not a coax or attenuator issue. Never thought to reduce squelch to 0 to restart lock on control channel. As long as system was programmed in and running, even if with other systems, no problems. But when I pressed FL key 2 Sys Key 2 (2.2) and turned off this trunk system, then turned back on, had to reduce squelch all the way down to zero for scanner to relock on CC. Then I tried this with my second 536HP, and indeed the exact same thing.
Never had this issue before with other scanners (396XT, 996XT, GRE/RS) It sounds like a minor thing, once you know about it, but I was knocking my head for hours to figure out what was going on. Maybe this is common knowledge for some scanner enthusiasts, but it is the first time I can recall having to set squelch on a trunk system all the way down to zero for a scanner to relock on the CC. The CC is strong, RSSI over 400 on ARC536 and on ARC XT PRO with 996XT. It is a loud system/CC.
Perhaps this may be an issue for some others who are getting intermittent performance on a specific trunk system with CC locking issues. Try kick starting the CC lock by dropping the squelch to zero. Then you can put the squelch back up.
JamesO, thanks again for your reply to my initial question.
Regards

Steve AA6IO