What's going on in PG????

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Dewey

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Drove around the Bowie area trying to listen to the apparently few fire talkgroups that are "Active" (Ch 1/TG 1133, Ch 2/TG 1135, etc.).... On the drive TG 1135 (8A2) stopped again - like someone either pulled the plug or the activity went away from some other reason.

Driving northeast a bit from Bowie into Crofton, the system nearly fades away again...

I sure hope they boost the power on this system...
Due to some of the discussions going on in the post PSR-800 thread over on the GRE forum, would it be a problem if you put your PSR-800 into search mode (?OPEN?) the next time you drive near the PG area? Since PGPD is full time TDMA, you may be the first who can answer if the PSR-800 is already capable of following TDMA.

Dewey
 

troymail

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Due to some of the discussions going on in the post PSR-800 thread over on the GRE forum, would it be a problem if you put your PSR-800 into search mode (?OPEN?) the next time you drive near the PG area? Since PGPD is full time TDMA, you may be the first who can answer if the PSR-800 is already capable of following TDMA.

Dewey
Sorry - I thought that was obvious -- it does.
:cool:
 

troymail

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W-O-W. I sure hopes Uniden plays "hurry up"! Since your answer was in open forum, I already added a link in the Uniden forum where I said, "http://forums.radioreference.com/uniden-scanners/205372-looks-like-gre-might-taking-lead.html". I hope you didn't mind.

Dewey
Not a problem..... I just wish I could receive it better from my house - I'm only 15 miles or so north of Bowie--

As I've posted before, I think these systems are getting more and more "tuned" to the point that soon you'll have to live inside the borders to listen unless you have a good rooftop antenna... the new Baltimore City P25 system is showing some similar characteristics....
 

chief34a

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For the guys talking about the sites and which is which, there are 21 sites in the county. 11 in the north loop (north of Rt 4) and 10 in the south loop with plenty of overlap. All the sites have the same freqs and you should be able to hear at least 3 sites from any point in the county but they did design the system to not operate very far outside the county............
 
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troymail

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For the guys talking about the sites and which is which, there are 21 sites in the county. 11 in the north loop (north of Rt 4) and 10 in the south loop with plenty of overlap. All the sites have the same freqs and you should be able to hear at least 3 sites from any point in the county.......
While driving around Bowie today I did see my radio locking into RR's reported Site 101 (mostly) and 102 (occasionally)... I guess the 21 sites are what make the system so fine tuned so as to only be easily received "within" the county....and pretty hard to receive outside.....
 

tolley

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Yes I suspect it is very fined tuned too, I work in Bowie and can see the tower (near the intersection of RT50 and RT3) from where I work. With my Pro 106 I can pick it up loud and clear at work but as soon as I head east on Route 50 the system starts getting more and more faint starting about 5 miles away from the PG County line. Just my observation.
 
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maus92

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PSR-800, TDMA, and PG

I'm not quite clear, Troy, are you saying that your PSR-800 is able to receive and track the PG TDMA signaling? If so, how is the quality of voice transmissions?
 

troymail

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I'm not quite clear, Troy, are you saying that your PSR-800 is able to receive and track the PG TDMA signaling? If so, how is the quality of voice transmissions?
I believe it's pretty good when I'm IN Prince George County -- about the same as other digital voice (FDMA).

The PG system is driving me crazy because it's just coming on line and fairly weak once you leave the County--

I guess what I'm saying here is I believe the PSR800 is working fine on the system and any issues I'm seeing are the PG system itself -- the only way I can confirm that is to try to listen to a 2nd TDMA system (the closest right now is Loudon County but I don't get over there too often).


Note: I have some recordings (yeah PSR800!) but I can't confirm if they are FDMA or TDMA since the usage of the frequencies by the system is somewhat dynamic. I try to capture and post a recording of a police talkgroup which are almost always TDMA (fire Ch1 is almost always FDMA and fire Ch2 bounces back and forth depending on the presence of FDMA only radios).

GRE NOTE: it would be nice to have an indicator on the display (and maybe in the recording too) that says "F" vs. "T".... maybe instead of "DG" display "dg" or something....
 
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HarryWilly

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Does anyone have a database of the pager tones going?

Also,... can someone be more specific about the changes to dispatching? I thought the CAD was pretty quick.

Also.... hopefully companies will start coming up with P25 Phase II compatible scanners soon... I can imagine this is taking the reverse engineering required to a whole different level (well it isn't all that much reverse engineering since it is an "open" standard).
 

rdale

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Also.... hopefully companies will start coming up with P25 Phase II compatible scanners soon...
You might be getting confused by the terminology - but the last few posts in this very thread confirm that it's already happened.
 

DaveIN

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TG 1133 (Fire Dispatch) is coming up in both TDMA and FDMA.....

This confirms that neither Ch1 or Ch 2 are always FMDA --
Troy, looking at the custom table setting in the program (via custom/edit), is the TDMA 2 setting automatically populated for you from the P25 data and nothing else is needed, correct? I'm hoping this is the ideal situation where nothing else is needed for this to work.

It appears this is the case from Franks previous post, but I just wanted to be sure.
 

troymail

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another TG?

Just listened to a HazMat box dispatch... assignment was on Ch 10 / 8A11 (which came up as TG 1069).

Interestingly, most of the initial incident was showing up as FDMA but later in the call, it switched to TDMA....

I suspect someone with an FDMA only radio heard the dispatch and listened (affiliated) with TG 1069 until the incident de-escalated and when that unit left the system and all on the TG were back to being only TDMA units, the system reverted to TDMA.

When the switch occurred, I can't tell the difference from the voice/decode quality - at least not from my location.
 

rkight

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Has anyone been able to monitor the police talkgroups? They are TDMA (as a rule). I am ready to buy a PSR-800, but I need the firm answer that it does in FACT do TDMA. Right now I am not completely clear.........
 

brownlab

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I live in Loudoun and I receive about 90% (my estimation) of the Public Safety TDMA traffic on my Uniden 996XT. My understanding that the reason this is occurring is because there are still a number of FDMA radios used in the field and the TDMA systems will accommodate FDMA units that have permission to broadcast in Loudoun. In other words, you should be able to monitor a TDMA system if any FDMA radios are broadcasting in PG such as MOCO or Fairfax Fire running mutual aid. Same should be true with the police if someone such as the FBI, Marshals, or whoever is broadcaster on the PG TDMA. Granted these are two different countries and PG is much bigger than Loudoun however I am going to Alexandria for a few days and will program in PG and see what I hear. Good Luck, I know it is a drag when you can no longer monitor a system that you have been listening to for years.
 

brownlab

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OK, I am monitoring on a Uniden 996XT from Alexandria and I am getting strong reception from Site 102 and CC 773.8812. I am receiving PGFD Disp and that is what my scanner displays however even though TGs are assigned at dispatch, none are displayed on the scanner during any transmissions. However I have monitored various transmissions between the unit and dispatcher such as "on scene" , "in service", and some situations reports so I feel that I am hearing more than just a simulcast of the PGFD Dispatch Channel. I have only been listening for about an hour and nothing much is going on so we will have to wait and see if any TAC channels come up during any multi-unit dispatch such as a fire or accident. Like the TDMA in Loudoun, you can put the 996XT on "hold" at the Control Channel and see the scanner go to the various Police TGs except you can't hear them. (Kind of makes you nuts). The PRS 800 receiving the PGPD TGs is great news!
 

Dewey

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OK, I am monitoring on a Uniden 996XT from Alexandria and I am getting strong reception from Site 102 and CC 773.8812. I am receiving PGFD Disp and that is what my scanner displays however even though TGs are assigned at dispatch, none are displayed on the scanner during any transmissions. However I have monitored various transmissions between the unit and dispatcher such as "on scene" , "in service", and some situations reports so I feel that I am hearing more than just a simulcast of the PGFD Dispatch Channel. I have only been listening for about an hour and nothing much is going on so we will have to wait and see if any TAC channels come up during any multi-unit dispatch such as a fire or accident. Like the TDMA in Loudoun, you can put the 996XT on "hold" at the Control Channel and see the scanner go to the various Police TGs except you can't hear them. (Kind of makes you nuts). The PRS 800 receiving the PGPD TGs is great news!

No you're not hearing simulcast... PGFD, TG 1133, had been operating FDMA since coming up. While yes you can park on the control channel and see the TGs go flashing by, it's much much better to just run something like Unitrunker or Pro96Com and watch the whole system in operation. It will give you a better understanding for what is happening, and should a piece of equipment operating on the 700 system switch channels, you will immediately see it in the affiliations if you know the RID. This way, you will have begun identifying the TGs, such as, when the dispatcher say "Ops on Channel 7, Talkgroup 8A7".

Dewey
 
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