Metro-25/MTA MRRS P25 System

[CqDx]

Seems like the Nassau/Suffolk County simulcast cell RFSS number and Site ID changed. I drove the whole length of LIE on Saturday and was able to pick up the system with a trunk mount cell phone like antenna on and off for about 45 minutes. The signal is not strong so I doubt every site within the simulcast cell is lit up.

No voice traffic or radio affiliations were captured.

 

[GTR8000]

Seems like the Nassau/Suffolk County simulcast cell RFSS number and Site ID changed. I drove the whole length of LIE on Saturday and was able to pick up the system with a trunk mount cell phone like antenna on and off for about 45 minutes. The signal is not strong so I doubt every site within the simulcast cell is lit up.

No voice traffic or radio affiliations were captured.

Are the control channels the same?

 

[CqDx]

Same five channels Harris site

 

[dave3825]

Picked up the cc here in East Islip. It was weak but decent enough to watch for any activity. Now I can't find an active cc.

 

[dave3825]

WHat exactly does this mean?

2019/06/12 14:46:39 Freq=774.281250 NAC=015 Blocking network ID change from 91FE826E to BEE0039A

Left this running today and found it in the event log.

Also not sure where the transmitter is. In East Islip, using an lna, I can get a cc. Drove to Stony Brook, Babylon, East Farmingdale and into Levittown and got no signal on my 436 at any of those locations.

 

[Thunderknight]

39A is NJ’s 700 system. As these are State license channels, your radio probably caught some signal coming from NJ. Or the system is telling radios to ignore that sysID. (I’m not sure if that’s a software message or coming from CC data stream.)

 

[GTR8000]

WHat exactly does this mean?

2019/06/12 14:46:39 Freq=774.281250 NAC=015 Blocking network ID change from 91FE826E to BEE0039A

Left this running today and found it in the event log.

Also not sure where the transmitter is. In East Islip, using an lna, I can get a cc. Drove to Stony Brook, Babylon, East Farmingdale and into Levittown and got no signal on my 436 at any of those locations.

It means that at some point, your receiver started picking up one of the NJICS sites. The WACN/SysID is the clue. Most likely the Neptune site, which uses 774.28125 as its primary control channel.

I want to reiterate that this MTA system is using a lot of low profile sites at rail stations and along the railway. These are not big booming sites in most cases, and are going to be tough to get a strong signal on unless a site happens to be nearby. Also, I hate to sound like a broken record, but the system is still in the early buildout stages, and thus will be in flux until all sites are operational and the final configuration is settled upon.

Edit: Credit to @Thunderknight for mentioning the NJICS just prior to my post

 

[CqDx]

Recently there are good band conditions and you might be picking up NJICS and the Pro96com (or whatever decoder) might be confusing the messages coming site.

NJICS Site 16 in Neptune is a straight shot over the ocean from Long Island, and they both uses 774.28125 as the control channel. Not really an issue for Motorola/Harris radios since it compares the control channel with System ID and WACN as well.

 

[dave3825]

After I posted I looked thru the event log some more and saw many group calls. And after the NJICS reply, those tgs seem to match system 39a. That's not a bad reach, E Islip to Jersey, with an amped indoor antenna...

So the message I asked about most likely is coming from DSDPlus it looks like..

Lol, my dsdplus.p25data file is a mess...

  Network: 91FE8.26E

  Bandplan #0:   Base=769.        Offset=+30     Spacing=6.25  BW=12.5
  Bandplan #1:   Base=762.00625   Offset=+30     Spacing=6.25  BW=12.5
  Bandplan #2:   Base=851.0125    Offset=-45     Spacing=12.5  BW=12.5  Slots=2
  Bandplan #3:   Base=762.00625   Offset=+30     Spacing=12.5  BW=12.5  Slots=2
  Bandplan #4:   Base=851.00625   Offset=-45     Spacing=12.5  BW=12.5  Slots=2
  Bandplan #8:   Base=769.        Offset=+30     Spacing=6.25  BW=12.5  Slots=2


    Site: 21.1   NAC=015

    Neighbor: 91FE8.39A-1.3
    Neighbor: 91FE8.39A-1.14
    Neighbor: 91FE8.39A-1.23
    Neighbor: 91FE8.39A-1.34
    Neighbor: 91FE8.39A-1.39

    Channel 1-1306:   770.16875             VOICE  DATA
    Channel 3-1306:   770.16875-1           VOICE
    Channel 3-1307:   770.16875-2           VOICE
    Channel 0-193:    770.20625    CC  SCC
    Channel 1-1346:   770.41875        SCC  VOICE  DATA
    Channel 3-1346:   770.41875-1           VOICE
    Channel 3-1347:   770.41875-2           VOICE
    Channel 0-311:    770.94375    CC  SCC
    Channel 0-727:    773.54375    CC  SCC
    Channel 0-771:    773.81875        SCC
    Channel 1-1924:   774.03125        SCC         DATA
    Channel 3-1924:   774.03125-1           VOICE
    Channel 0-845:    774.28125    CC  SCC
    Channel 1-1964:   774.28125    CC


--------------------------------------------------------------------------------------------------

  Network: 91FE8.39A


    Site: 1.3

    Channel 1-1430:                CC


    Site: 1.14

    Channel 1-1966:                CC


    Site: 1.16   NAC=015


    Site: 1.23

    Channel 1-1190:                CC


    Site: 1.34

    Channel 1-1810:                CC


    Site: 1.39

    Channel 1-2004:                CC


--------------------------------------------------------------------------------------------------

 

[GTR8000]

Lol, my dsdplus.p25data file is a mess...

Yikes, it sure is. Very little contained in that file is legit, a ton of cross-contamination with the NJICS. This is what the file should look like:

Network: 91FE8.26E

  Bandplan #0:   Base=769.        Offset=+30     Spacing=6.25  BW=12.5
  Bandplan #8:   Base=769.        Offset=+30     Spacing=6.25  BW=12.5  Slots=2


    Site: 21.1   NAC=015

    Channel 0-193:    770.20625    CC  SCC
    Channel 0-311:    770.94375    CC  SCC
    Channel 0-727:    773.54375    CC  SCC
    Channel 0-771:    773.81875        SCC
    Channel 0-845:    774.28125    CC  SCC

 

[GTR8000]

Update on the system as of a few days ago:

Metropolitan Regional Radio System (MRRS)

25 12.5 kHz 700 MHz channel pairs in use (5 channels each in 5 simulcast zones)

64 above ground sites in the system. 54 currently on the air. 61 of 64 constructed. All 64 expected online by October 2019.

 

[APEXNext]

Seems like the Nassau/Suffolk County simulcast cell RFSS number and Site ID changed. I drove the whole length of LIE on Saturday and was able to pick up the system with a trunk mount cell phone like antenna on and off for about 45 minutes. The signal is not strong so I doubt every site within the simulcast cell is lit up.

No voice traffic or radio affiliations were captured.

What program are you using here...

 

[GTR8000]

What program are you using here...

That's Pro96Com, which requires a compatible scanner in order to decode P25 control channels.

 

[hakwye8518]

active control channel 770.94375 rfss id 21 site: 1. wacn 91fe8 sys id 26e rssi-97dbm picking this up in sayville with an sds200

 

[62Truck]

Quote,
Update on the system as of a few days ago:

Metropolitan Regional Radio System (MRRS)

25 12.5 kHz 700 MHz channel pairs in use (5 channels each in 5 simulcast zones)

64 above ground sites in the system. 54 currently on the air. 61 of 64 constructed. All 64 expected online by October 2019.

Looks like they will have their system fully functional before Orange County.

 

[dave3825]

picking this up in sayville with an sds200

Can't figure out where the xmitter is. Was in Oakdale / Sayville just now and 436 got nothing. I do get it In East Islip with sdr and an lna. I am seeing that my sdr is more sensitive than my 436 as the 436 wont pick up any cc using the same lna and ant as my sdr...

 

[hakwye8518]

@dave3825 i was getting full signal strength in west islip montauk highway by robert moses causeway.

 

[hakwye8518]

thinking there's a transmitter at the babylon yard. not sure how to go about getting an exact location and confirmation

 

[GTR8000]

thinking there's a transmitter at the babylon yard. not sure how to go about getting an exact location and confirmation

Park somewhere nearby, remove antenna from scanner. If the control channel is still very strong, then you're in the "hot zone". Look for three antennas on a monopole or tower in the area like the ones the arrows are pointing to in this photo.

 

[hakwye8518]

Via google street view. Next time I’m in the area I’ll remove the antenna on my scanner.