Unidentified system C62

[kb5udf]

Hi gang, I'm picking up a strong CC, on 856.7375, which I realize has been previously used on the LFT 800 type II system, but no longer is being used per unitrunker (I scan it regularly). However, It look like this frequency is not an FDMA P25 control channel, and is quite strong to me here in Lafayette, but I can't figure out what system this is suppposed to be on. DSDplus seems to be decode the control channel, but not SDRtrunk.

Anybody know what this sys is.?

ERR17 NET_STS_BCST WACN ID=BEE00 SysID=C62 LRA=0 CC=856.7375 SC=60
Sync:+P25p1 TSDU ERR9 Opcode=5 MFID=90 05 90 C0 3F BF 00 00 00 00 00
ERR14 IDEN_UP_TDMA ID=2 Base=851.0125 Offset=-45 Spacing=12.5 BW=12.5 Slots=2
ERR14 MOT_BSI_GRANT Null BSI ch=856.7375

 

[slayer816]

Did you get any P25Data off of it from DSD?

Could be a Parish/City services system. There is a possibility that it's too strong and/or you may have interference.

 

[ruraloperationsgroup]

The Lafayette parish system is still in use, primarily as a backup to the LWIN. My understanding is that it is coming off line soon.

 

[kb5udf]

The Lafayette Parish 800 system is used daily for city services. It is also a backup for LWIN. I don't know about plans to replace or cancel it (but I'll check in with some of my contacts). Here is some DSD plus data I logged:

Network: BEE00.C62

Bandplan #0: Base=851.00625 Offset=-45 Spacing=6.25 BW=12.5
Bandplan #2: Base=851.0125 Offset=-45 Spacing=12.5 BW=12.5 Slots=2


Site: 1.1

Channel 0-537: 854.3625 VOICE
Channel 0-917: 856.7375 CC
Channel 0-953: 856.9625 SCC
Channel 0-985: 857.1625 VOICE
Channel 0-1113: 857.9625 SCC
Channel 0-1273: 858.9625 SCC

I see in my log group calls on TG 3477 and one affiliation on 3661. Overall, VERY little activity so far, this suggests a system in test mode?

 

[dave3825]

What Nac is being shown?

 

[kb5udf]

None. The other p25 systems in my log file show the NAC after the Site, but this one does not. It may be that my DSDplus version is WAY out of date (fastlane from about 2 years ago or more) as I haven't updated it.

 

[GTR8000]

To be clear, the System ID is C62, not 62C as in the thread title. Looks to be a pretty standard 800 MHz ASTRO 25 Phase II system. I suspect the NAC would be C61 for Site 1.1

 

[kb5udf]

Thanks GTR. MODS if you would please correct the thread title.

 

[dave3825]

Normally you need to click report and describe the issue.

 

[KevinC]

Normally you need to click report and describe the issue.

Fortunately I'm not normal.

 

[mtindor]

The Lafayette Parish 800 system is used daily for city services. It is also a backup for LWIN. I don't know about plans to replace or cancel it (but I'll check in with some of my contacts). Here is some DSD plus data I logged:

Network: BEE00.C62

Bandplan #0: Base=851.00625 Offset=-45 Spacing=6.25 BW=12.5
Bandplan #2: Base=851.0125 Offset=-45 Spacing=12.5 BW=12.5 Slots=2


Site: 1.1

Channel 0-537: 854.3625 VOICE
Channel 0-917: 856.7375 CC
Channel 0-953: 856.9625 SCC
Channel 0-985: 857.1625 VOICE
Channel 0-1113: 857.9625 SCC
Channel 0-1273: 858.9625 SCC

I see in my log group calls on TG 3477 and one affiliation on 3661. Overall, VERY little activity so far, this suggests a system in test mode?

All of those freqs are on the Lafayette license. So it sounds like they stood that new system up to replace the old Type II. What do I know though -- I'm in Ohio.

At any rate, that is a Motorola system so it would be an FDMA control channel. If you are having trouble monitoring it and you are within Lafayette, you probably need to lower your gain way down (as someone else suggested). SDRTrunk should have no problem copying it, and DSDPlus should copy it without error, assuming a decent signal (but not too strong) and no interference. The license suggests it is single-site, so it would be C4FM. But, if it is a simulcast you'd have to set SDRTrunk to LSM (or at least should). The difficulty in copying is more likely a signal issue or an issue with your dongle PPM being off.

 

[kb5udf]

Ok, re-configured my setup a bit and used one of my new dongles (airspy) as I think my 10 year old original airspy is dying. Voila!
Decoding like a champ in sdrtrunk now. I've got to get some real work done, but I'll report back when I am able to hear some voice traffic.

Activity Summary - Decoder25 Phase 1 Normal (C4FM)

Network
WACN:BEE00[781824] SYSTEM:C62[3170] NAC:C61[3169] LRA:00[0]

Current Site
SYSTEM:C62[3170] NAC:C61[3169] RFSS:01[1] SITE:01[1] LRA:00[0] STATUS:ACTIVE RFSS NETWORK CONNECTION
PRI CONTROL CHANNEL:0-917 DOWNLINK:856737500 UPLINK:811737500
SEC CONTROL CHANNEL:0-1113 DOWNLINK:857962500 UPLINK:812962500
SEC CONTROL CHANNEL:0-1273 DOWNLINK:858962500 UPLINK:813962500
SEC CONTROL CHANNEL:0-953 DOWNLINK:856962500 UPLINK:811962500
STATION ID/LICENSE:

Neighbor Sites
UNKNOWN
Frequency Bands
BAND:0 FDMA BASE:851006250 BANDWIDTH:12500 SPACING:6250 TRANSMIT OFFSET:-45000000
BAND:1 FDMA BASE:762006250 BANDWIDTH:12500 SPACING:6250 TRANSMIT OFFSET:30000000
BAND:2 TDMA BASE:851012500 BANDWIDTH:12500 SPACING:12500 TRANSMIT OFFSET:-45000000 TIMESLOTS:2
BAND:3 TDMA BASE:762006250 BANDWIDTH:12500 SPACING:12500 TRANSMIT OFFSET:30000000 TIMESLOTS:2

 

[dave3825]

So now that the dongle is working, is the smart zone system still running?

 

[kb5udf]

Yes. They are running tests with talkgroups on the analog Type II system, patched to the new P25 system. They are testing encryption and in the clear, but given then that our overlords here are so controlling of information they even encrypt animal control, I would be shocked if the system winds up having any public safety in the clear once it is being used.