Fairfax County P25 system

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mikev

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I notice there's not a lot of info on this system yet... I just picked up a PSR-800 (for both Loudoun County decoding and the record feature)... I'm thinking I may run it next to my Uniden on the current Motorola system and see if I can get any matches between the two. I've already noticed TGs that haven't been identified or added to the DB yet... just in less than 5 minutes of recording.

Is anyone else actively working to get more info on this system?
 

mikev

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I'm thinking Town of Herndon PD Dispatch might be TG 1311.

I've heard two different traffic stops in different parts of the town on this talkgroup. I'll keep a closer eye on it, but it's sounding pretty good.
 

jethunder

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I've matched P25 TG1018 with TG16288 ("Gang 2") on the Public Safety trunk (one radio on the P25 TG and another radio on the Public Safety trunk)...

Also on the P25 system, the list I'm building has:
TG1001 = PD district 8 (Sully) dispatch
TG1053 = PD district 6 (Franconia) dispatch...
TG1059 = PD 2 (Mt. Vernon) or 6 dispatch (the two districts are often patched together)...
TG1083 = PD districts 3 and 5 dispatch
TG1089 = PD districts 1 & 8 dispatch
TG1125 =Inova Fairfax Hospital
TG1233 = Adult Detention Center
TG1235 = "Tac 1"; mention of "transfer a prisoner" so also thought to be Adult Detention Center
TG1237 = think it's also Adult Detention Center
TG1293 =Fairfax City PD
TG1295 =Fairfax City PD
TG1297 = "Tac 1" for unknown jurisdiction
TG1299 = "Tac 2" for unknown jurisdiction
TG1305 = Vienna PD dispatch
TG1311 = Herndon PD dispatch
TG1315 = Herndon PD Tac 2
TG1319 = unknown, but a mention of the corner of "Sterling and Herndon Parkway"
TG1313 = unknown but a mention of "(garbled) and Missouri"

Corrections welcome!
 

c5corvette

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I've matched P25 TG1018 with TG16288 ("Gang 2") on the Public Safety trunk (one radio on the P25 TG and another radio on the Public Safety trunk)...
Using your example above, do the math... if you take 16288/16=1018 (3FA hex).

I am pretty sure there was an earlier post from someone else that said none of the TGIDs are really changing from the old system to the new system.
 

mikev

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I am pretty sure there was an earlier post from someone else that said none of the TGIDs are really changing from the old system to the new system.
I've been out of the loop on these things for a while now (wasn't even aware of the P25 system until a couple weeks ago)...

So is this an eventual migration from Motorola to P25? Is it going to only be used for Police, or will all public safety move to this system? Given the limited number of frequencies in this system (at least as of this time), will TDMA eventually come into effect on it?

And one comment... from my residence in central Loudoun, I have a lot more trouble picking up this system than the Motorola one...
 
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c5corvette

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I've been out of the loop on these things for a while now (wasn't even aware of the P25 system until a couple weeks ago)...

So is this an eventual migration from Motorola to P25? Is it going to only be used for Police, or will all public safety move to this system? Given the limited number of frequencies in this system (at least as of this time), will TDMA eventually come into effect on it?

And one comment... from my residence in central Loudoun, I have a lot more trouble picking up this system than the Motorola one...
From what I understand from another user in these forums, the P25 system will replace the existing public safety system and all users on the existing public safety system will migrate. So far only the schools and the sheriff have officially migrated. There was also a previous post online here that stated they would not implement TDMA.

As for your reception...
a) while it doesn't impact a commercial radio as much, P25 systems seem to be a bit less effective when it comes to reception range on a scanner
b) I think both the old and new systems may be a bit weak lately to scanners since the County is running both systems sharing same sites / antennas (without getting real technical - just think two different transceivers per one antenna) and reception may or may not get better after rebanding if they retune antennas and turn off one system.
 

freqhopping

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Today they were having some problems with interference on the new system. They mentioned having some sort of wideband interference particularly in the Arlington area and the FCC is supposed to be coming out to track it down.
 

mikev

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Brought my PSR-800 with me to work today, since I can't pick this system up at home. I see a new frequency - 855.3875 - and also a bunch of new TGs... Going by the same hex TG IDs as the Motorola system, I've seen...

1233 - ADC Ops
1239 - ADC Logistics
1253 - FCSO Pre-Release Community Labor Force
1257 - FCSO Courts Ops
1261 - FCSO Juvenile/Domestic Court
1263 - FCSO Circuit Court
1267 - FCSO Courts Security
1273 - FCSO General District Court
1295 - Fairfax City PD Dispatch
1305 - Vienna PD Dispatch
1311 - Herndon PD Dispatch

I have it scanning these to record and hopefully verify for certain, but just quickly listening as it goes, these are sounding pretty good. So it looks like others are or will soon be using this system more. As for FCPD, I've only seen FCPD 1/8 active on it today... no other FCPD on it.

And of course, just after I post, I get a new TG that doesn't have a hex ID in the Motorola system... TG# 1519 (hex 5EF). This TG appears to be for radio testing, as I've heard a number of "Testing 1 2" and "Loud and clear" kinds of traffic on it.
 
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mikev

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FCPD 4/7 has joined the party... still no 2/6 or 3/5 seen today...

I'll be verifying my recordings this afternoon when I get home... some of these are looking pretty good though, just from what I've been hearing. I've also run across some additional TGs since my list this morning... FCPD Motorcyle Ops, Vienna Tac1, a few more courts and ADC...

And my Pro96Com has shown one of the alternate control channels also used for voice once, which I suppose isn't necessarily an unusual thing, especially with only four "voice" frequencies on a system like this.
 

mikev

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I see that jethunder found TG 1059 (Hex ID 423) as FCPD 2/6 Dispatch... but in the DB, TG 1404 (Hex ID 57C) is labeled as being FCPD 2/6.

TG 22464 (Hex ID 57C) does not exist on the Motorola system, which leads me to question whether 1404 is really active on the P25 system for this purpose. I haven't seen any activity in either TG 1059 or 1404 today, so I don't have anything to verify either of these myself... but given the correlation of the hex IDs between the systems, I'm more likely to believe that 1059 is the correct TG ID for FCPD 2/6, since that matches with a TG on the Motorola system.

Is the person who submitted 1404 as the TG ID for FCPD 2/6 Dispatch around, by chance?
 

mikev

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After reviewing the recordings from today, I just submitted a bunch of talkgroups... 6 new Sheriff TGs for the ADC and Courts, Police Dispatch TGs for Fairfax City, Vienna, and Herndon, and one new FCPD TG.

I would imagine that they'll appear in the DB sometime this evening or tonight.

Meanwhile, looking through the affiliation log today, I found a number of other TGs... going solely by the TGIDs, they should be three Herndon PD Tac channels (2, 3, 4), Vienna and Fairfax City PD Tac 1 channels, and three FCFD channels (two hospitals and channel 4B Response). I'll be adding these in tonight to see if anything shows up tomorrow.
 

freqhopping

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TG 22464 (Hex ID 57C) does not exist on the Motorola system, which leads me to question whether 1404 is really active on the P25 system for this purpose. I haven't seen any activity in either TG 1059 or 1404 today, so I don't have anything to verify either of these myself... but given the correlation of the hex IDs between the systems, I'm more likely to believe that 1059 is the correct TG ID for FCPD 2/6, since that matches with a TG on the Motorola system.
22464 used to be in the database. Not sure who removed it or when? It's a simulcast of Ch 2/6.


There's nothing cryptic about any of the talkgroups on this new system. No need to listen to them to figure them out. Like c5corvette said, just multiply the TGID by 16 and you will have the TGID for it on the old system. I've already created complete systems for my scanners for when it's completely online.
 

mikev

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Well, if there aren't any issues with it then, I'll just submit TGs to the database as I see them become active in Pro96Com without doing any audio verification. Obviously that makes it a lot easier, but if some changes are made in the migration, they won't be immediately apparent with this assumption.
 

mikev

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Oooo... Lots of radio testing going on today... over 40 radios have affiliated to TG 1519 so far today, which has been used for testing. Also, saw some traffic on TG 1101, which equates to FCFD 4A Dispatch... seen other TGs popping up here and there as well in the affiliation log... so they're definitely getting ready to put more people on this new system.
 

c5corvette

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22464 used to be in the database. Not sure who removed it or when? It's a simulcast of Ch 2/6.


There's nothing cryptic about any of the talkgroups on this new system. No need to listen to them to figure them out. Like c5corvette said, just multiply the TGID by 16 and you will have the TGID for it on the old system. I've already created complete systems for my scanners for when it's completely online.
I was just repeating what one of the county users posted on here before. Its confirmed info. The easiest solution is have the admin copy and paste all the talkgroups from old to new and then if there are any new ones or changes found add them. No need for mikev to do it one at a time.
 

freqhopping

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I was just repeating what one of the county users posted on here before. Its confirmed info. The easiest solution is have the admin copy and paste all the talkgroups from old to new and then if there are any new ones or changes found add them. No need for mikev to do it one at a time.

Yep.

To create my new systems I copied my existing file info into excel, created a formula to divide by 16 and then pasted the resulting TGID + description into the new files.
 

mikev

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I certainly don't mind that, IF they'll just copy the info. That's the question, I suppose. If they will, then I'll stop sending updates, and will just post here with what I'm seeing.

Lots of testing today it seems... A few radios in and out of the testing TG (1519)... just had one radio run through 5 nearly sequential TGs above the testing one (1521, 1523, 1525, 1527, and 1529), and a couple others have been in and out of a couple of them... some alerts and unit-to-unit communication between the radios on these TGs...

Seen a couple more FCFD TGs getting affiliated to... still no traffic from them though.
 
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