P25 control channel on 150.995

[nunyax]

A couple of days ago I started hearing digital data on 150.995. I entered it into my PRO-106 tonight and it recognized it as P25 trunking with full-scale signal strength on the stock antenna. After creating a TSYS, it's showing no system ID but does show a NAC of 561.

I am suspecting it may be for Barrow County since the signal is so strong (I'm in Monroe.) Barrow has 3 FCC applications pending for microwave links but no other applications/licenses for a trunked system.

Also, 156.240 is full-scale signal strength with data but it's not being recognized as a control channel by the scanner. Does anyone have any info for this new system?

 

[b7spectra]

It could be being used as an MDT channel.

 

[CSHIFTLT]

yes barrow is going p25 vhf, but unaware of which freq's....

 

[nunyax]

The control channel changed this morning. 150.995 is silent but am now monitoring it on 156.165. 156.240 is also silent today.

 

[nunyax]

The control channel changed this morning. 150.995 is silent but am now monitoring it on 156.165.

That didn't last long. Control channel now switched to 151.0775.

 

[cabletech]

nunyax, doing a FCC ULS license check, I do not see any of the freq's that you have listed as belonging to anyone in either Monore Co. or Walton Co.

What I do see is that all these freq's are licensed thru out the state as public works freq's which means that they could be used for data transfer as well as voice.

I also do not see any VHF trunking systems listed for GA. so highly unlikly that these are control channels on a trunking system.

 

[nunyax]

nunyax, doing a FCC ULS license check, I do not see any of the freq's that you have listed as belonging to anyone in either Monore Co. or Walton Co.

What I do see is that all these freq's are licensed thru out the state as public works freq's which means that they could be used for data transfer as well as voice.

I also do not see any VHF trunking systems listed for GA. so highly unlikly that these are control channels on a trunking system.

Then my scanner must be defective. And I would have never thought to check the ULS. I just depended on that little birdie to tell me they had the pending MW applications.

 

[nunyax]

Info from Unitrunker:

System ID 056C
150.995, 151.0775, 151.175, 156.165
TG activity:
TG 100 = 28 hits 12/26
TG 26 = 32 hits 12/24

 

[MTS2000des]

Info from Unitrunker:

System ID 056C
150.995, 151.0775, 151.175, 156.165
TG activity:
TG 100 = 28 hits 12/26
TG 26 = 32 hits 12/24

According to the ULS, only 6 licenses are issued for 151.0775:
Trenton, GA (Dade county), Lincoln county, Jones county, Coffee county, Pickens co Jail and Moultrie PD. None of these are anywhere near you except Pickens county.

150.995 is in use by many south Ga and rural North GA agencies, and Clayton county- note Clayton county has recently changed their license to reflect 11K2F3E for narrowband analog but not digital voice.

 

[nunyax]

As stated earlier, I believe it's located in Barrow County. I am aware of what's found in the ULS license database. A ULS application search does show 3 pending applications for microwave licenses for Barrow and Barrow is moving to a new multi-site system, details of which I don't know. Whoever it is would have to explain why they are transmitting before being licensed.

 

[N8IAA]

Joe, does Unitrunker show whether or not it is decoding P-25 Phase I/II, Mototrbo, or, NXDN? I know that they have been pushing the last two for the counties running VHF/UHF.
Larry

 

[N8IAA]

Extremely strong signal near the Mall of GA. Couldn't get the 106 to decode the signal. It also didn't sound like P-25 when in the analzye mode.
Larry

 

[nunyax]

Joe, does Unitrunker show whether or not it is decoding P-25 Phase I/II, Mototrbo, or, NXDN? I know that they have been pushing the last two for the counties running VHF/UHF.
Larry

Yep, UniTrunker shows TYPE as APCO P25, ID as BEE00-56C, MODULATION as C4FM. Much more activity today as totals now are 213 users for 47 groups. Possibly it's Phase II as both my 396T and 106 track the talkgroups but don't decode much if any voice unless these are just a lot of key ups with no talking. Another oddity is that my 396T shows the 056C system ID but the 106 shows no system ID, just the 561 NAC.

I'm running Audacity to record from the 396T. This afternoon it only recorded a total of 56 seconds of sound, mostly just chirps but a couple of instances I could hear distorted voice. Only 2 of the talkgroups are showing encrypted calls (1 and 175.)

Almost all the group hits occurred on 156.240.

 

[Jay911]

Another oddity is that my 396T shows the 056C system ID but the 106 shows no system ID, just the 561 NAC.

This is strong evidence that the system uses "multi-block" data to communicate certain trunking characteristics. Note this thread:

http://forums.radioreference.com/gre-scanners/244048-psr-500-600-vhf-p25.html

As DonS says at the end of the thread, if your system uses the "extended" (multi-block) method of identifying the SID and WACN, etc., your GRE-built scanner will not display that data.

The benefit of the "extended" network ID packet vs. the "standard" (single block) one appears to be that it allows for the specification of a unique TX frequency - necessary for VHF and UHF trunking systems where there isn't necessarily a guaranteed offset value like there is in the 700/800 band(s).

 

[GTR8000]

Possibly it's Phase II as both my 396T and 106 track the talkgroups but don't decode much if any voice unless these are just a lot of key ups with no talking.

On the Info tab of the Site window, what does it say for Channel Access? P1 = Phase I, X2 = X2-TDMA, P2 = Phase II

 

[nunyax]

It does say "Channel Access: P1." And I can confirm the voice traffic. At this moment Barrow County Central is conducting radio checks with fire and EMS apparatus and personnel on TGID 25. I switched to the attic antenna and am hearing them fine. The signal had been full scale on the rubber duck but the error rate must have been too high to decode before. Now decoding great!

 

[nunyax]

Barrow County Central instructed all SO units on 155.130 analog to switch over to LE Dispatch 1 on the new system at 10:17.

Lots of encrypted activity on TGID 1.

 

[rapidcharger]

It's barrow alright.
They just went quiet.

They don't appear to have a license though.

I'd say that the only thing left to listen to is Clayton county but if they're on that .995 frequency, reception is going to be wiped out up here.

 

[Buttabean]

Barrow Countys New Radio System

I see that Barrow county was updated today to show it on a P25 Digital Radio System now with a control channel of 150.99500MHz so i guess what u were hearing was actually their new system. I guess i can delete barrow cty outta my scanner now cuz its gonna be a dead band from now on. Another one bites the dust!

Barrow County Public Safety System Trunking System, Winder, Georgia - Scanner Frequencies

A couple of days ago I started hearing digital data on 150.995. I entered it into my PRO-106 tonight and it recognized it as P25 trunking with full-scale signal strength on the stock antenna. After creating a TSYS, it's showing no system ID but does show a NAC of 561.

I am suspecting it may be for Barrow County since the signal is so strong (I'm in Monroe.) Barrow has 3 FCC applications pending for microwave links but no other applications/licenses for a trunked system.

Also, 156.240 is full-scale signal strength with data but it's not being recognized as a control channel by the scanner. Does anyone have any info for this new system?

 

[Buttabean]

Clayton County Is Switching To P25 Digital Trunking System

Im in clayton & they will be on P25 probably before the end of 2013. Its in the works now. Analog scanners will only be good for stateband monitoring, ham radio monitoring, railroads, wal-mart, taxi cabs, retail stores, and for SHTF situations. When i bought my PSR-310 i was thinking it wouldnt need upgrading for a few years but i was wrong...again!

It's barrow alright.
They just went quiet.

They don't appear to have a license though.

I'd say that the only thing left to listen to is Clayton county but if they're on that .995 frequency, reception is going to be wiped out up here.