RadioReference on Facebook   RadioReference on Twitter   RadioReference Blog
 

Go Back   The RadioReference.com Forums > U.S. Regional Radio Discussion Forums > Maryland Radio Discussion Forum

Maryland Radio Discussion Forum Forum for discussing Radio Information in the State of Maryland.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1 (permalink)  
Old 01-31-2013, 7:40 PM
Member
   
Join Date: Dec 2008
Location: BCo, OC MD / Dutchess NY
Posts: 381
Default UMBC MOTOTRBO

UMBC just switched to a MOTOTRBO system today:
ULS License - Industrial/Business Pool, Trunked License - WQQE411 - MARYLAND, STATE OF - UNIVERSITY OF MD BALTIMORE COUNTY - Frequencies Summary
WQQE411

I was going to submit this just now, but even with DMRDecode and DSD running to sort this thing out, I'm having trouble understanding what exactly it is. Given the number of freqs in the license, I was leaning towards thinking it was a Capacity Plus before it came online. Now that it has, I'm not so sure.

452.0 is currently the only active repeated vox channel, with voice traffic for UMBCPD exclusively on that freq, Color Code 1, Time Slot 1, Group Address 6.

The Group address makes me think it's a trunked TRBO system of some variety (since that appears to be the TRBO version of a talkgroup), but I have a very scant understanding of these, even having read just about everything on here about them. I'm not seeing the CSBK or FLCO traffic indicative of Capacity Plus systems. When vox traffic comes online, all I get is a voice header giving the Color code, service options, group address, and source address. So.. standalone repeater? If anybody on here has TRBO experiece and can shed some light on this, that would be fantastic. Further info as requested.
__________________
APX7000 UHF1/700/800, PSR800, KG-UVD1P
XPR 7550, M7100, P7100IP user
OC / UMBC
Reply With Quote
Sponsored links
        
  #2 (permalink)  
Old 01-31-2013, 10:04 PM
dtscho's Avatar
Member
  RadioReference Database Admininstrator
Database Admin
 
Join Date: Aug 2001
Location: Fredericksburg, VA
Posts: 1,249
Default

You could post the text file that is generated in DMRDecode. If it's a Capacity Plus trunked system, there will be references to Capacity Plus in the log file. And seeing a group is normal on both TRBO standalone repeaters as well as Capacity Plus systems.

The license does indicate the system is supposed to be trunked, but it sounds like they may be using it as individual repeaters.

Dave
Reply With Quote
  #3 (permalink)  
Old 01-31-2013, 10:08 PM
dtscho's Avatar
Member
  RadioReference Database Admininstrator
Database Admin
 
Join Date: Aug 2001
Location: Fredericksburg, VA
Posts: 1,249
Default

Looking over the license some more, it may be a Connect Plus system, since the license lists two sites. Do you hear a continuous "control channel" sound on any of the frequencies?

Dave
Reply With Quote
  #4 (permalink)  
Old 01-31-2013, 11:41 PM
Member
   
Join Date: Dec 2008
Location: BCo, OC MD / Dutchess NY
Posts: 381
Default

Negative, but what I've heard says that TRBO trunking doesn't depend on a CC. I get status bursts on 452.0 about every 2 minutes, but that's it.

Here's a snippit including vox transmission from DMRDecode:

Code:
Slot Type : Colour Code 1 Terminator with LC
Group Voice Channel User LC
Service Options : Non-emergency/No priority
Group Address : 6 Source Address : 31
12:37:14 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:14 AM Short LC : Act_Updt - Group voice activity on BS time slot 1 Hashed Addr 18 : No activity on BS time slot 2
12:37:14 AM DMR Data Frame
Slot Type : Colour Code 1 Terminator with LC
Group Voice Channel User LC
Service Options : Non-emergency/No priority
Group Address : 6 Source Address : 31
12:37:18 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:18 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : First fragment of LC 
12:37:18 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:18 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Continuation fragment of LC
12:37:18 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:18 AM Short LC : Act_Updt - Group voice activity on BS time slot 1 Hashed Addr 18 : No activity on BS time slot 2
12:37:18 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Last fragment of LC
12:37:18 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:18 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Single fragment LC 
12:37:18 AM Embedded Single Block LC : 00011100011011010010110010011110
12:37:18 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:18 AM Short LC : Act_Updt - Group voice activity on BS time slot 1 Hashed Addr 18 : No activity on BS time slot 2
12:37:18 AM DMR Voice Frame
12:37:19 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:19 AM Short LC : Act_Updt - Group voice activity on BS time slot 1 Hashed Addr 18 : No activity on BS time slot 2
12:37:19 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Continuation fragment of LC
12:37:19 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:19 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Continuation fragment of LC
12:37:19 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:19 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Last fragment of LC
12:37:19 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Single fragment LC 
12:37:19 AM Embedded Single Block LC : 00011100011011010010110010011110
12:37:19 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:19 AM DMR Voice Frame
12:37:19 AM DMR Data Frame
__________________
APX7000 UHF1/700/800, PSR800, KG-UVD1P
XPR 7550, M7100, P7100IP user
OC / UMBC
Reply With Quote
  #5 (permalink)  
Old 02-01-2013, 12:38 AM
Spleen's Avatar
Member
  Premium Subscriber
Premium Subscriber
 
Join Date: Dec 2002
Location: Baltimore
Posts: 659
Default

I scanned around the other frequencies listed, the only traffic I've been able to catch is your voice traffic on 452.000...right now I'm listening to them trying to find some salt to put on an icy walk using DSD 1.6 in inverted mode.
But I did notice there are some bursts that don't get decoded--I wonder if they have to be monitored seperately in non-inverted mode to glean any other info....?


Quote:
Originally Posted by dpcain View Post
Negative, but what I've heard says that TRBO trunking doesn't depend on a CC. I get status bursts on 452.0 about every 2 minutes, but that's it.

Here's a snippit including vox transmission from DMRDecode:

Code:
Slot Type : Colour Code 1 Terminator with LC
Group Voice Channel User LC
Service Options : Non-emergency/No priority
Group Address : 6 Source Address : 31
12:37:14 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:14 AM Short LC : Act_Updt - Group voice activity on BS time slot 1 Hashed Addr 18 : No activity on BS time slot 2
12:37:14 AM DMR Data Frame
Slot Type : Colour Code 1 Terminator with LC
Group Voice Channel User LC
Service Options : Non-emergency/No priority
Group Address : 6 Source Address : 31
12:37:18 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:18 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : First fragment of LC 
12:37:18 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:18 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Continuation fragment of LC
12:37:18 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:18 AM Short LC : Act_Updt - Group voice activity on BS time slot 1 Hashed Addr 18 : No activity on BS time slot 2
12:37:18 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Last fragment of LC
12:37:18 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:18 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Single fragment LC 
12:37:18 AM Embedded Single Block LC : 00011100011011010010110010011110
12:37:18 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:18 AM Short LC : Act_Updt - Group voice activity on BS time slot 1 Hashed Addr 18 : No activity on BS time slot 2
12:37:18 AM DMR Voice Frame
12:37:19 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:19 AM Short LC : Act_Updt - Group voice activity on BS time slot 1 Hashed Addr 18 : No activity on BS time slot 2
12:37:19 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Continuation fragment of LC
12:37:19 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:19 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Continuation fragment of LC
12:37:19 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:19 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Last fragment of LC
12:37:19 AM DMR Voice Frame with Embedded Signalling
EMB : Colour Code 1 : Single fragment LC 
12:37:19 AM Embedded Single Block LC : 00011100011011010010110010011110
12:37:19 AM DMR Data Frame
Slot Type : Colour Code 1 Idle
12:37:19 AM DMR Voice Frame
12:37:19 AM DMR Data Frame
Reply With Quote
Sponsored links
  #6 (permalink)  
Old 02-01-2013, 9:27 AM
Member
   
Join Date: Jan 2009
Posts: 3
Default

Quote:
Originally Posted by dpcain View Post
Negative, but what I've heard says that TRBO trunking doesn't depend on a CC. I get status bursts on 452.0 about every 2 minutes, but that's it.
The burst you're hearing every 2 minutes is probably the beacon for an IP Site Connect system. This beacon informs subscribers they are within range of the repeater. The radios then decide which site to affiliate with based on certain parameters set up in the CPS.

IPSC uses multi-casting (simultaneous transmisson on multiple frequencies) so all traffic is retransmitted on all repeaters in the IPSC system at the same time (not necessarily on both slots). In other words, you will always hear all radio traffic on 452.000mHz even if the subscribers have roamed to another site.

But if you're within range of the other repeater frequencies and you're not hearing them, assuming they are running at licensed ERP, it may be a stand-alone repeater. But the "burst" sounds to me like an IPSC beacon.
Reply With Quote
  #7 (permalink)  
Old 02-01-2013, 10:28 AM
dtscho's Avatar
Member
  RadioReference Database Admininstrator
Database Admin
 
Join Date: Aug 2001
Location: Fredericksburg, VA
Posts: 1,249
Default

OK, thanks for posting the text file. This looks like a standalone repeater. There are no references to Capacity Plus or Connect Plus in the text.

Regarding TRBO and control channels, Connect Plus systems do use a dedicated control channel. They also have a System ID.

Dave
Reply With Quote
  #8 (permalink)  
Old 02-01-2013, 10:32 AM
Member
   
Join Date: Dec 2008
Location: BCo, OC MD / Dutchess NY
Posts: 381
Default

Oh wowza, cool. I'm also getting a simulcast on 461.9125 today of all UMBCPD traffic.

Which when I look it up indicates that that's the second site on Performing arts, and 462 is the primary on the Library. Not sure how to put that one in the DB...
__________________
APX7000 UHF1/700/800, PSR800, KG-UVD1P
XPR 7550, M7100, P7100IP user
OC / UMBC

Last edited by dpcain; 02-01-2013 at 10:36 AM..
Reply With Quote
  #9 (permalink)  
Old 02-01-2013, 1:06 PM
Spleen's Avatar
Member
  Premium Subscriber
Premium Subscriber
 
Join Date: Dec 2002
Location: Baltimore
Posts: 659
Default

Analog or via DSD? All I'm getting right now on 461.9125 is data bursts...and I'm actually wondering if it really is UMBC because the signal is so weak...


Quote:
Originally Posted by dpcain View Post
Oh wowza, cool. I'm also getting a simulcast on 461.9125 today of all UMBCPD traffic.

Which when I look it up indicates that that's the second site on Performing arts, and 462 is the primary on the Library. Not sure how to put that one in the DB...

Last edited by Spleen; 02-01-2013 at 1:13 PM..
Reply With Quote
Sponsored links
  #10 (permalink)  
Old 02-01-2013, 1:20 PM
Member
   
Join Date: Dec 2008
Location: BCo, OC MD / Dutchess NY
Posts: 381
Default

DSD, with RSSI so strong and close to that of the library site the only difference is a slightly higher DSD error rate.
__________________
APX7000 UHF1/700/800, PSR800, KG-UVD1P
XPR 7550, M7100, P7100IP user
OC / UMBC
Reply With Quote
  #11 (permalink)  
Old 02-01-2013, 1:55 PM
Spleen's Avatar
Member
  Premium Subscriber
Premium Subscriber
 
Join Date: Dec 2002
Location: Baltimore
Posts: 659
Default

Hmmmm....so I tune back to 452.000, and that signal is still blowing me out of the water. Almost perfect DSD voice decoding. And they're still fussing about salting the walks...
Any guesses as to why the disparity?







Quote:
Originally Posted by dpcain View Post
DSD, with RSSI so strong and close to that of the library site the only difference is a slightly higher DSD error rate.
Attached Images
  
Reply With Quote
  #12 (permalink)  
Old 02-01-2013, 3:55 PM
Spleen's Avatar
Member
  Premium Subscriber
Premium Subscriber
 
Join Date: Dec 2002
Location: Baltimore
Posts: 659
Default

Speaking of the RRDB, has anyone come up with some sort of convention for listing MOTO systems? A prime example of a "broken" entry right now is Johns Hopkins. I'd submitted the MOTO changes ages ago, but the way it's currently listed, one might assume that certain services were heard only on the listed frequencies, but now with MOTO entering the picture, the listings should probably look more like a trunked system entry. Sorta like the entry for the National Aquarium....?



Quote:
Originally Posted by dpcain View Post
Oh wowza, cool. I'm also getting a simulcast on 461.9125 today of all UMBCPD traffic.

Which when I look it up indicates that that's the second site on Performing arts, and 462 is the primary on the Library. Not sure how to put that one in the DB...

Last edited by Spleen; 02-01-2013 at 3:55 PM.. Reason: Crappy typing
Reply With Quote
  #13 (permalink)  
Old 02-01-2013, 6:28 PM
dtscho's Avatar
Member
  RadioReference Database Admininstrator
Database Admin
 
Join Date: Aug 2001
Location: Fredericksburg, VA
Posts: 1,249
Default

I fixed the JHU frequencies, removing the specific users, since they could have changed after they migrated to TRBO.

But no, JHU should not be treated like the National Aquarium system. That is a Capacity Plus trunked system, and the JHU repeaters are standalone.

Dave
Reply With Quote
  #14 (permalink)  
Old 02-01-2013, 8:25 PM
Spleen's Avatar
Member
  Premium Subscriber
Premium Subscriber
 
Join Date: Dec 2002
Location: Baltimore
Posts: 659
Default

Awesome, got it.


Quote:
Originally Posted by dtscho View Post
I fixed the JHU frequencies, removing the specific users, since they could have changed after they migrated to TRBO.

But no, JHU should not be treated like the National Aquarium system. That is a Capacity Plus trunked system, and the JHU repeaters are standalone.

Dave
Reply With Quote
  #15 (permalink)  
Old 02-02-2013, 12:02 AM
Member
   
Join Date: Dec 2008
Location: BCo, OC MD / Dutchess NY
Posts: 381
Default

Spleen, I think the simplest logical explanation (if I go by lex parsimonae) you have a high-order obstruction between you and the PAHB site, but you have clear direct signal from the Library. I don't know how close you are to UMBC or on what bearing, but that seems to be the most likely issue.
__________________
APX7000 UHF1/700/800, PSR800, KG-UVD1P
XPR 7550, M7100, P7100IP user
OC / UMBC
Reply With Quote
Sponsored links
  #16 (permalink)  
Old 02-02-2013, 2:58 PM
Spleen's Avatar
Member
  Premium Subscriber
Premium Subscriber
 
Join Date: Dec 2002
Location: Baltimore
Posts: 659
Default

I'm guessing...anything can go wrong between Hilltop Drive and Midtown...


Quote:
Originally Posted by dpcain View Post
Spleen, I think the simplest logical explanation (if I go by lex parsimonae) you have a high-order obstruction between you and the PAHB site, but you have clear direct signal from the Library. I don't know how close you are to UMBC or on what bearing, but that seems to be the most likely issue.
Reply With Quote
  #17 (permalink)  
Old 02-05-2013, 2:43 PM
Spleen's Avatar
Member
  Premium Subscriber
Premium Subscriber
 
Join Date: Dec 2002
Location: Baltimore
Posts: 659
Default

And now to complicate things even better, I'm getting sporadic voice and somewhat less sporadic MOTO data on 155.550, a recently updated KIL428 frequency for UMBC that does NOT carry the emission designator for MOTO. Anyone know if this is being brought in to the UHF system or is there another plan in place? The traffic was definitely LE comms.

DMRDecode data attached.
Attached Files
File Type: zip 155550.zip (353 Bytes, 10 views)
Reply With Quote
  #18 (permalink)  
Old 02-05-2013, 3:42 PM
dtscho's Avatar
Member
  RadioReference Database Admininstrator
Database Admin
 
Join Date: Aug 2001
Location: Fredericksburg, VA
Posts: 1,249
Default

There's no voice data on this file, but it does indicate that color code 1 is being used on 155.5500. I added the frequency to the database.

Dave
Reply With Quote
  #19 (permalink)  
Old 02-05-2013, 3:55 PM
Spleen's Avatar
Member
  Premium Subscriber
Premium Subscriber
 
Join Date: Dec 2002
Location: Baltimore
Posts: 659
Default

I didn't let that capture run long enough to grab the voice packets...I still can if you would like. Right now I've got DSD trying to record .wav files of the voice traffic...


Quote:
Originally Posted by dtscho View Post
There's no voice data on this file, but it does indicate that color code 1 is being used on 155.5500. I added the frequency to the database.

Dave
Reply With Quote
  #20 (permalink)  
Old 02-05-2013, 4:08 PM
dtscho's Avatar
Member
  RadioReference Database Admininstrator
Database Admin
 
Join Date: Aug 2001
Location: Fredericksburg, VA
Posts: 1,249
Default

Yes, having the voice traffic on the DMRDecode file would be great. Thanks.

Dave
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 8:06 PM.


Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
All information here is Copyright 2012 by RadioReference.com LLC and Lindsay C. Blanton III.Ad Management by RedTyger
Copyright 2011 by RadioReference.com LLC Privacy Policy  |  Terms and Conditions