Central Texas P25 (Austin / Travis Co)

[SCPD]

Looking at some data from the Austin / Travis County P25 system which is expected to grow over the next couple of years into counties north and south of Travis.

I see two interesting site numbers ... 001-010 and 001-020. That's one-dash-ten and one-dash-twenty in english. Your radio may display this as 01-0A and 01-14 (the hexadecimal equivalents).

The first one has a control channel number of 01-0394. The second has a control channel number of 00-1113. The leading "00" usually indicates 800 mhz. The leading "01" usually means 700 mhz. In fact, this is the only channel I have listed that isn't 800 mhz. I need to get some data from the Uvalde area but that's another story.

The 001-010 control frequency calculates out to 764.46875

The 001-020 control frequency calculates out to 857.9625

That second frequency looks like a Williamson county control channel.

The 700 mhz frequency is active but too far to be usable. At the moment ... I can't hear any Wilco control channels.

 

[W5TWX]

I can't seem to understand where your getting this information from. Can you explain this a little better?

 

[SCPD]

I'm looking at the control channel data (Unitrunker logs) from sites 1 and 2.

Some of the messages describe band plans so that I can convert a channel number to a frequency. Other messages describe neighboring sites (the site number and active control channel) and the source for this new site information.

I think part of of what I'm seeing is the early vestiges of the migration of Williamson County to P25.

The state of Texas used to have a number of 700 frequencies licensed but now I can't find them.

-rick

 

[SCPD]

Williamson County has a P25 control channel

After a little driving ... confirmed Williamson county frequency 857.9625 is broadcasting a P25 control channel. It's simulcast - same as sites 01-01 and 01-02. Self advertised as site 01-14 with same WACN and Sysid as the Austin / Travis County system.

So far no voice traffic.

The Wilco Motorola system is still active.

 

[SCPD]

I'm still puzzled over not being able to find a license for the 764.46875 control channel. The closest I could find was this ...

http://wireless2.fcc.gov/UlsApp/UlsSearch/license.jsp?licKey=2377059

The above is more of a blanket placeholder for build-out than an actual operating license. Is there a "legit" license for this site?

 

[nd5y]

The above is more of a blanket placeholder for build-out than an actual operating license. Is there a "legit" license for this site?

Actually it is a "legit" license. 700 MHz State License are for blocks of frequencies in a geographic area, the same as cellular carriers. The individual sites are not listed on the license. They can be anywhere and use any frequency.

 

[SCPD]

Doesn't that defeat the purpose / role of the FCC to track who is licensed and who isn't. That license is for the state and covers the whole 700 mhz band. Does that mean no city or county can obtain a 700 mhz license?

Within the realm of public safety, the state isn't the biggest user of spectrum - it's the populous counties and large metropolitan areas. Am I the only one that thinks this is bizarre?

-rick

 

[nd5y]

Nope. There are regional planning organizations that coordinate frequency use in each of the 55 regions.

 

[FlashSWT]

Wasn't DPS supposed to be rolling out a 700Mhz trunked system at the Capitol? Could 764.46875 be related to that?

.

 

[SCPD]

Nope. There are regional planning organizations that coordinate frequency use in each of the 55 regions.

Tom ... thank you for point this out. I did some digging. The FCC allows the governor of each state to apply for a statewide license of the 700 mhz public safety spectrum. The regional committees take over coordination. Central Texas falls into region 49. Turns out they have their own website which is (surprise) http://www.region49.org/. Here is a link to their proposed 700 mhz plan. According to the FCC, this plan has to be approved not just by the Region 49 members but also by the adjacent regions (in this case the other 5 Texas regions) with final approval resting with the FCC. Reading through I find the state-wide license covers licensed operation for all mobile-to-mobile communications within the state but not for operating from a fixed location.

Another interesting note is that Region 49 handles coordination of 25 khz channels. The applicant is effectively getting 2 (12.5 khz wide) or 4 (6.25 khz wide) channels at a time.

If you make your way to Section 3.6 of the document, it states that spectrum applicants must ...

1. (include) FCC Form 601 (or its equivalent form as required by the FCC) with all
appropriate schedules and attachments;
2. a description of the proposed system;
3. a justification for the additional spectrum;
4. a proposed system loading schedule;
5. a proposed system implementation schedule;
6. an interference prediction map using the current version of TIA/EIA TSB 88
guidelines;
7. documents indicating agency-funding commitments sufficient to fund the
development of the proposed system(s);
8. a list of all frequencies that will continue to be used by the applicant, and their
specific uses;
9. a list of “give-back” channels, if applicable;
10. a list of all Region 49 entities with co-channel or adjacent channel assignments,
and a statement indicating the date and manner by which each of these entities was
notified of this application; and
11. a statement acknowledging the FCCs deadline of 12/31/2016 for operating at 6.25
KHz channel spacing, or its equivalent.

So if I understand this right ... the Region 49 committee does handle coordination but ultimately a Form 601 must be filed with the FCC.

Here's the rub ... the above document is a draft proposal. I haven't seen actual acceptance from the FCC. I think I read that Region 40 (north Texas) was accepted but not Region 49. Region 49 might not yet have the rubber stamp to begin approving spectrum coordination.

However, either way ... an FCC license is required for fixed station operation (such as a trunked system). If I'm wrong, please say so ... with links / references to back it up!

-rick

 

[Russell]

Here's the Region 40 plan also. Check out the host site as well - the National Public Safety Telecommunications Council???

http://www.npstc.org/documents/Submitted Region 40 700 MHz Plan.pdf

 

[SCPD]

Unitracker,
I would like for you to comment a little more on this statement please, "I need to get some data from the Uvalde area but that's another story." I am assisting a fellow with programming his 396T for this specific city/county and our first attempt crashed and burned. I now have noticed the "Middle Rio Grande Talk Groups". I had him program the 4 frequencies into the scanner and had him set it to ID Search. He has heard nothing. The frequencies he input were the ones found on the GATRRS page for Uvalde. I will be in contact with him soon to correct another issue in regards to DPS P25 programming. I would be interested to read what you know about this area. Thanks a bunch.