Montgomery County P25 system update

maus92

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The county has stated that their new 700 MHz system will start testing during the summer of 2020. I would monitor 769.30625 for control channel activity.
 

HM1529

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The system is on the air. It has been for a while now. If you do CC monitoring, you can see radios affiliating sometimes as public safety personnel fiddle with radios that have both the old and new system programmed. It just isn't officially "active" as of yet. They ran in to unanticipated delays in completing some of the tower sites and the whole project was on hold.

 

maus92

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Interesting they are still using a two site design. The freq I mentioned was full on with some sort of data, but not a control channel per se. Perhaps it was a test.Montgomery Co PA cch.PNG
 

HM1529

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I have not run anything on the CC's for a while. I can take a look and see if anything has changed. I just pulled it up on my G5 the other day and the pager monitored Site 4 with the 851.8875 CC. No traffic, of course, but it saw the "East" system.
 

maus92

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Makes sense. 851.8875 is no longer on the East Smartzone site, (nor is 854.9675.) I have not had the chance to look at licensing.
 

HM1529

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Site 4 is showing as:

851.8875 cc
852.2625 alt
852.3750 alt
853.7625 alt

Neighbor: Site 3

Site 3 is showing as:

851.7750 cc
852.1375 alt
852.6500 alt
853.4500 alt

Neighbor: Site 4

I am getting a strong signal on both 769.30625 and 770.30625. It is a pulsing white noise sound on both. It sounds sort of like a CC data stream, but it is not.
 
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GTR8000

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The freq I mentioned was full on with some sort of data, but not a control channel per se. Perhaps it was a test.
I am getting a strong signal on both 769.30625 and 770.30625. It is a pulsing white noise sound on both. It sounds sort of like a CC data stream, but it is not.
It's a test pattern for talk-out bit error rate testing, very typical with Motorola ASTRO 25 systems during the coverage acceptance testing phase.

PS - Minor correction for the East cell: 769.30626 should be 769.30625
 

HM1529

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It's a test pattern for talk-out bit error rate testing, very typical with Motorola ASTRO 25 systems during the coverage acceptance testing phase.

PS - Minor correction for the East cell: 769.30626 should be 769.30625
Huh. That typo must have been there for a while. Tonight, I only deleted an extra alt cc frequency that was listed. Any way, I just went in and fixed that.
 

HM1529

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It's a test pattern for talk-out bit error rate testing, very typical with Motorola ASTRO 25 systems during the coverage acceptance testing phase.

PS - Minor correction for the East cell: 769.30626 should be 769.30625

So, is it a data stream that Moto techs monitor in the field with a special piece of equipment?

Coverage acceptance testing is not something I've done.
 

maus92

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I've seen a presentation by a Motorola project manager that described the process. It basically uses a laptop with loaded with proprietary testing software, a "golden" mobile radio that has been precisely calibrated, a mag mount antenna, and a GPS antenna. A team drives through the system footprint to test every grid square to verify the BER that was specified in the contract. The software senses when it is a new grid square, initiates a test sequence, and records the result.
 
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wa8pyr

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I've seen a presentation by a Motorola project manager that described the process. It basically uses a laptop with loaded with proprietary testing software, a "golden" mobile radio that has been precisely calibrated, a mag mount antenna, and a GPS antenna. A team drives through the system footprint to test every grid square to verify the BER that was specified in the contact. The software senses when it is a new grid square, initiates a test sequence, and records the result.
Very slick package, very expensive so there aren't many of them; it has a specific name which escapes me at the moment (for some reason "Voyager" springs to mind but I don't think that's it). They get into the system and put a selected frequency into test mode (which takes it out of the trunking rotation) and program the mobile test platform for the same frequency.

When we installed our new P25 system, Motorola brought the package out and we drove around the county doing our BER testing. That was a long day sitting on my butt in the passenger seat of a Ford Expedition.
 

radio3353

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Per the September 30, 2020 issue of Montco's Public Safety News, cut over to the new system is now scheduled for December, 2020. Getting close at last (maybe)!
 

GTR8000

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cavmedic

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Being the system is in testing phases and there is traffic , it could clean up the forums if all the threads were merged to one. Keeps it easier to find, but just my opinion...
 

Ryanwr944

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A friend of mine is saying all Montgomery county will be encrypted including fire we will no longer be able to hear Montgomery county
 

radio3353

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A friend of mine is saying all Montgomery county will be encrypted including fire we will no longer be able to hear Montgomery county
Other than your mystical friend, do you have anything more concrete to back up that statement? Or is this just an attempt at fake news? Just askin' ;)
 

kh11

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A friend of mine is saying all Montgomery county will be encrypted including fire we will no longer be able to hear Montgomery county
I have heard nothing to that effect, and you can be fairly sure that there would have been quite a lot of discussion (within the fire companies if not here) long before now if that were going to be the case.
 
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