UCSD Moto TRBO

[inigo88]

Hey guys,

I've been monitoring the UCSD 800 MHz TRS (system ID 6501) and it's essentially dead. There is little to no traffic for hours at a time.

The campus shuttle buses ("Shuttle Ops" channel) are equipped with Motorola XPR 4500 mobiles, which support analog & TRBO digital on VHF and UHF. The quality of the receive audio is definitely digital, so it must be TRBO (and covers a large enough area that it is likely repeated). I originally suspected an RCS talkgroup due to the digital audio but the radio doesn't appear to support P25/trunking.

This is just a heads up to look for UCSD users that would have been on the TRS elsewhere (UHF conventional TRBO?). Anyone have any more information?

 

[MtnBiker2005]

A rumor I heard about that private bus company sometime first of this year/late last year.
They were going be kicked off the UCSD trunked system. I don't know when/if they left the system. I heard they had Motorola ASTRO radios for the UCSD system at the time in analog mode.

They were dealing with commusa.com (Communications USA) for their new communication needs.
COMMUSA company is big on MOTOTRBO repeaters.

I also heard Fisher Wireless now have MOTOTRBO repeaters on the air in San Diego County area.

Should look up the shuttle bus company name(s) in the FCC license database.

 

[inigo88]

I was digging around the UCSD UHF licenses, but it didn't occur to me that the shuttles were contracted out. Will give that a try. Thanks!

Edit: Any idea what the company name is? All I can find is UCSD Transportation & Parking Services.

 

[MtnBiker2005]

I don't know the company name off hand.
If you know someone in the area. Have them look at the drivers work shirt for a company logo,etc... ?

 

[inigo88]

I recently moved to the area (just updated my location). Drivers are UCSD student employees. According to their online job application Shuttle Operations is located "in the trailer behind building D in the Campus Services Complex." So if they are contractors there's no mention of it on the job application, and if they aren't it's a mystery as to why they're no longer using the 800 MHz TRS in favor of the TRBO system, which doesn't seem to be licensed under UCSD.

Might just have to resort to a signal-stalker hit already. :lol:

 

[inigo88]

Confirmed TRBO on 462.0125 / 467.0125 RM - WQKM878. Repeater is licensed to the roof of the Stuart Commons Building in Muir College at UCSD. Licensee name is "Regents of the University of California," which must be a newer license since "University of California" and other variants also exist in the FCC database.

FCC Callsign WQKM878 Details

I've spotted the TRBO HTs (XPRs) in use by building and grounds maintenance personnel, and I believe the Campus Security Officers (not UCPD, which is on the RCS North) may carry them as well. Therefore it looks like this is not limited to the shuttle buses and a campus-wide move from the analog 800 MHz TRS to a UHF MotoTRBO digital system has occurred. The 800 MHz trunking system is still operating but appears to be in a backup capacity only.

 

[inigo88]

More TRBO heard on 463.2125 RM, also licensed to locations on campus.

FCC Callsign WQIX604 Details

 

[inigo88]

Here's a full list based on the FCC license data (I skipped the UHF licenses with Regents in all caps since they were acquired earlier):

461.7875 / 466.7875 - WQLI381 - RM
461.8625 / 466.8625 - WQLI381 - RM
462.0125 / 467.0125 - WQKM878 - RM (CONFIRMED!)
462.1375 / 467.1375 - WQKX329 - RM
463.2125 / 468.2125 - WQIX604 - RM (CONFIRMED!)
463.5125 / 468.5125 - WQKX329 - RM
463.9125 / 468.9125 - WQIX604 - RM
463.9875 / 468.9875 - WQIX604 - RM
464.4125 / 469.4125 - WQIX604 - RM
464.8625 / 469.8625 - WQIX604 - RM

I agree with MtnBiker and I think this new system was set up and licensed on behalf of UCSD by CommUSA in Escondido. This system may not actually be that new at all, because I believe they're using the GPS-data feature on the XPR 4550 to run the shuttle tracking system (UC San Diego Shuttles).

The repeater locations in the licenses are on the west side of campus in Muir (I suspect on the roof of the AP&M building) and at the Central Utilities Plant/Telecom Service Yard behind York Hall in Revelle.

 

[inigo88]

462.1375 / 467.1375 - WQKX329 - RM CONFIRMED!
463.5125 / 468.5125 - WQKX329 - RM CONFIRMED!
463.9875 / 468.9875 - WQIX604 - RM CONFIRMED!

With each repeater being 2-slot TDMA that gives 10 channels so far for voice or data.

 

[monitor142]

Last I heard is UCSD is shutting down their 800 system end of this year. They decided not to upgrade the 800 system which is past end of support. The PD moved to RCS and all other entities on campus are setting up TRBO (and maybe analog) on UHF. Basically going back to the fragmented everyone for themselves just like pre 800 days. Pretty sad but I think the current budgets dicate the move away from the 800 trunker.

Based on the FCC license I checked, it looks like Day Wireless is setting up some if not all of their stuff.

-M142

 

[inigo88]

Update: May be a "Capacity Plus" (single site trunking) system.

Using Ian Wraith's DMRDecode java program I was able to determine the following about the 463.5125 repeater on the system:

Signal: Inverted
Color Code 1
Talkgroups: 201 (may be shuttles), 106
Users: 633, 1162, 1777

 

[LAflyer]

I recall seeing a blurb in some document last year that the entire UC system was to transition away from the 800Mhz systems in the next decade
Here in LA, they have joined as a member to the planned regional LA-RICS P25 system, however I also have heard they are reviewing standalone options as well.

Regarding MOTO TRBO I can't wait till we see widely available scanners that can receive this technology. More and more business users, along with even public safety folks have made the switch.

 

[inigo88]

UCSD's system is definitely mototrbo Capacity Plus trunking. Having finally gotten DSD working, all the user-talkgroups that were formerly on the 800 MHz Smartnet system are alive and well on the capacity plus system, minus UCSD Police & CSOs which are on the San Diego County RCS.

The system operates much like LTR (in that it doesn't have a control channel), however there is no system controller! Users bounce around between the following frequencies:

462.0125
462.1375
463.2125
463.5125
463.9875

I noticed today 463.9875 has some interference both from another distant mototrbo system AND an LTR Passport system which overpowers it with the beacon subaudible data bursts.

 

[karldotcom]

I was reading up on the RCS site and saw this entry from last year. With that kind of price per radio for UCSD, I imagine that going with Mototrbo for non-emergency communications would be a lot cheaper in the long run.

RCS Board Minutes – August 5, 2010
Page 5
8.5 Request the RCS Board’s approval for San Diego State University Police Department
to increase their maximum limit up to 100 units.
Staff recommendation/background: Staff recommends approval. On March 11, 2003
the RCS Board signed the customer service agreement with the SDSU Police
Department up to 60 radios. Subsequent amendments were made for an additional 20
SDSU radios. If approved, this request will increase their limit by 20. They are
currently replacing their analog radios with digital radios. Based on 100 radios, SDSU
will bring estimated annual revenue of $31,800 for system maintenance and $58,284
for system infrastructure to be deposited to the RCS Trust Fund
M/S/A (Beard/Yarborough)
Votes: AYES - 08
NOES – 0

 

[inigo88]

Using DMRDecoder and our latest conclusions on the digital CSBK message formatting in the Understanding Capacity Plus Trunking thread, I have mapped the UCSD system out as follows.

University of California, San Diego
Mototrbo - Capacity Plus Trunking
Color Code 1
Licenses: WQKX329, WQIX604
(DSD Signal: Invert)

Logical Channel Number (LCN) IDs: (Two per frequency, 1 per TDMA voice channel slot.)

LCN 1, 2 - 462.1375 MHz
LCN 3, 4 - 463.5125 MHz
LCN 5, 6 - 463.2125 MHz
LCN 7, 8 - 463.9875 MHz (Unconfirmed)

Talk Groups:

103
105
106
201
204
214

Like LTR trunking and its variants, Capacity Plus has no control channel. Instead a designated Rest Channel (in UCSD's case, with a 2 second data burst "beacon") rotates through the system frequencies. Unlike LTR which defaults to consistent home repeater LCNs, capacity plus puts all idle radios on the same rest channel. When a voice call is started, that existing channel is used and the left over radios not part of that talk group are kicked over to a new rest channel frequency (refer to the other thread for more details).

Therefore to map out the LCN IDs on UCSD's system I used two methods. First, the current LCN of an in progress voice call is announced in CSBK data messages. Second, when the nonparticipating radios are sent to a new rest channel, that Rest Channel LCN is announced in more CSBK data during the original voice call (much like an LTR data message indicating the current "Goto" LCN and the "Free" LCN at once). Thus you can get both the two LCNs of the frequency with the voice call in use, then quickly scan the other known system frequencies until arriving on the 2 second data burst on a new frequency, and recognize this new frequency as the new rest channel (whose LCN was also announced on the first frequency).

463.9875 MHz is for sure part of this system as a voice channel, the only reason I listed it as "unconfimed" is because I haven't yet directly identified it as LCN 7 or 8. However some Motorola literature on Capacity Plus trunking indicates that only 8 voice LCNs are available total, meaning 463.9875 would have to be the last two.

Furthermore, I thought I recalled seeing voice traffic on 462.0125 MHz, but it does not decode properly in DMRDecode and may be an extra data only channel.

 

[wa6yvx]

Which bits are the "source id"

 

[wa6yvx]

Today's log

Thanks for the info inigo. I scanned just those 4 freqs today and here is an excerpt of my log, which shows one having a colour code of 2. Maybe the higher group numbers are another system on the same frequency. I also know that the group id of 16777215 is the all call id to all units.

CACH : TACT Ch 1 First fragment of LC
Slot Type : Colour Code 2 Terminator with LC
Group Voice Channel User LC
Service Options : Non-emergency/No priority
Group Address : 1 Source Address : 2002
10:11:30 AM DMR Data Frame

The following 27 users were logged ..

1 GROUP Group Calls only (Only used channel 1)
4 Group Calls only (Used both channels)
102 Group Calls only (Only used channel 2)
103 Group Calls only (Used both channels)
106 GROUP (Only used channel 2)
113 Group Calls only (Only used channel 1)
114 Group Calls only (Only used channel 1)
122 Group Calls only (Used both channels)
201 GROUP (Only used channel 1)
204 GROUP (Only used channel 1)
575 Group Calls only (Used both channels)
583 Group Calls only (Used both channels)
599 Group Calls only (Used both channels)
607 Group Calls only (Used both channels)
797 Group Calls only (Only used channel 1)
1162 Group Calls only (Used both channels)
1310 Group Calls only (Used both channels)
1766 Group Calls only (Used both channels)
1772 Group Calls only (Used both channels)
1777 Group Calls only (Used both channels)
1809 Group Calls only (Used both channels)
2001 Group Calls only (Only used channel 1)
2002 Group Calls only (Only used channel 1)
2005 Group Calls only (Only used channel 1)
2006 Group Calls only (Only used channel 1)
16776412 GROUP (Only used channel 1)
16776413 GROUP (Only used channel 2)

 

[inigo88]

Lindsay has started supporting Mototrbo Capacity Plus, and I've created the system in the database!

 

[MtnBiker2005]

University of California (San Diego) - MOTOTRBO Capacity Plus
http://www.radioreference.com/apps/db/?sid=7087

 

[LAflyer]

Cool.

Now just need to get my hands of a MOTOTRBO capable receiver. Seemingly more people are making the switch here in the LA metro area.