PG County's P25 System

[m4a3t]

I am currently monitoring PG County's new P25 radio system. It appears they are testing the system with Fire/EMS. I picked up two talkgroups and a number of voice channels. It appears to be trunking and is not garbled. Control channel is 774.68125.

[ka3jjz]

and what radio are you using? Interesting bit of news. Are they simulcasting from the 490 side?

73 Mike

[m4a3t]

I'm using a PSR-500 with a Radio Shack 800Mhz antenna. Don't know whether they were simulcasting. I wasn't listening to those frequencies on my other radio. I did pickup two talkgroups: TG2001 and TG2003 and voice channels on 769.00 thru 772.00s. I can't be more exact because for some strange reason the system doesn't show up in Win500's activity log or the Object 'Notes' field even though everything else does but it does show up in the display in the Monitor/Control section of Win500.

[baybum]

Is this the same system that they said no scanner can monitor? Or has something changed?

[m4a3t]

Yes it is and they did say that. I vaguely recall reading here that there are certain modes the system could operate in that would allow it to interface with other area systems. That could be it.

[ocguard]

Originally Posted by m4a3t

Yes it is and they did say that. I vaguely recall reading here that there are certain modes the system could operate in that would allow it to interface with other area systems. That could be it.

From what I recall, the system is dual-mode (TDMA and FDMA). Most fire/EMS talk groups will operate in FDMA mode to allow non-TDMA radios (mutual aid) to interoperate. FDMA talk groups should be monitorable by P25 700mhz capable scanners. TDMA talk groups -- who knows.

[ka8ypy]

Fireboard will have several channels/talk groups that will be dual mode TDMA/FDMA, when an FDMA radio comes up the sytem will revert to FDMA, but when no FDMA radio is on the system it will be TDMA.

Police, Sheriff, and everyone else will be TDMA only at this point.

Dan
KA8YPY

[fd2119]

At the risk of confusing the already muddy waters, I was told (by my department rep, who went to a briefing about the system) that there will be three (or maybe it was codeplugs...) - north, central, and southern. The northern area will be FDMA, and the others, as I recall, will be TDMA.

Remember that this is coming third hand, but the person who told me this is highly reliable, and I trust him to know what he's talking about. I was told this about 2 months ago.

This is not to say that things haven't changed, though!

[m4a3t]

PG's systems is on the air again. It appears that EMS is using it at Redskin's Stadium. I was wondering if monitoring TDMA would possible with just a firmware update to current scanners when or if licensed to manufacturers or would new hardware be required.

[gesucks]

From today ball game, submitted to DB


Frequency Use
774.68125 Control Channel
774.20625 Alternate Control Channel
774.15625 Alternate Control Channel
773.88125 Control Channel
773.63125 Alternate Control Channel
773.23125 Alternate Control Channel
773.13125 Voice
772.90625 Alternate Control Channel
772.88125 Voice
772.48125 Alternate Control Channel
772.09375 Voice
771.78125 Voice
771.73125 Voice
771.18125 Voice
770.61875 Voice
770.25625 Voice
769.28125 WQJU814
769.75625 WQJU812

Talkgroups
2001
2003
2005

Sites Control Channel
101 774.68125
102 773.88125

Channel ID Plan Base Frequency Spacing kHz offset MHz band width kHz
1 851.00625 6.25 -45 6.25
2 762.00625 6.25 30 6.25

Radio ID's
249
2528001
2528004
2528050
2528114
2528124
2528126
2528127
2528129 was denied once on tg 2001
2528130
2528138
2528140

[m4a3t]

Hey thanks GEsucks. This is a treasure trove of information. Will plug these in immediately.

[bradam2001]

How would you program this on the 396 scanner.
I am lost
Thanks for any help

[baybum]

And how would you program the GRE scanner?

Do you have files already saved that you can share?


Mike

[bradam2001]

Is this system a LT, EDACS or P25
Thanks

[ResQguy]

Originally Posted by bradam2001

Is this system a LT, EDACS or P25
Thanks

Note the thread title "PG County's P25 System"

[Dispatcher308]

Folks,

I attended a class in Prince George County this past week and speaking to some Batt. Chiefs and Majors from the Fire Dept. they advised the system is up and running and has tested very well,l I was advised that some are going to have vehicle repeaters in them and everything is ready to go.

However the only downfall to this is that they are not gonna use the new system untill the new comm center has been built.


Just FYI

[ka3jjz]

And that would be expected (approximately) when, Nathan?

This would be a dandy little article for the wiki - particularly any hints/tricks necessary to correctly track this system. Offsets, hi/lo channels, ect. - anything at all would work...73 Mike

[gesucks]

PG Co P25 system
WACN BEE00
System ID 2A8
RFSS 1
Site 1 (101)

[gesucks]

PG Co P25 system

WACN BEE00
System ID 2A8
RFSS 1
Site 1 (101)
774.68125 Control Channel
774.20625 Alt Control Channel
774.15625 Alt Control Channel
773.63125 Alt Control Channel
769.75625 WQJU-812
769.28125 WQJU-814

Site 2 (102)
773.88125 Controla Channel
773.23125 Alt Control Channel
772.90625 Alt Control Channel
772.48125 Alt Control Channel
770.05625 WQJS917

Talkgroups
DEC 2001 HEX 7D1 Used for Redskins game
DEC 2003 HEX 7D3 Used for Redskins game
DEC 2005 HEX 7D5 Used for Redskins game

Channel plan
#0 Base freq 851.00625 Mhz Tx offset -45Mhz Spacing 6.25 kHz Bandwidth 6.25 kHz
#1 Base freq 762.00625 MHz Tx offset 30 MHz Spacing 6.25 kHz Bandwidth 6.25 kHz

[ka3jjz]

The wiki article has been constructed here...

Trunktrackers and the new PG County 700 Mhz System - The RadioReference Wiki

Extensions can now pull the system frequencies; when the talkgroups are entered, I'll install the extensions for those. There is a refresh link at the bottom in tiny print so the article can change when the database does.

There are sections set aside for each of the 6 scanners that can do 700 mhz (digital) trunking, as well as talkgroups. 73 Mike