Woodway, Texas Trunking

Ensnared · #1 (**permalink**) 11-16-2011, 10:21 AM

Recently, I observed a Woodway K-9 unit driving at a high rate of speed through Woodway, Texas. When I attempted to tune into the excitement, the conventional frequency did elicit the usual chatter. So, I went into the RR DB and eventually searched the FCC. If I am not mistaken, they were granted permission for a trunking system.

ULS License - Public Safety Pool, Trunked License - KBJ926 - WOODWAY, CITY OF

I went over to my trusty Pro-2042 and entered the frequencies shown on the FCC DB. It was not too long before I heard CC noises on one of the frequencies listed, 155.535.

Since I have hardly any experience analyzing trunking systems, I improvised on the assumption this was a Motorola system. Hence, I downloaded the Waco-McClennan County TSY & then modified the frequencies.

I don't know if this will work, but I am going to try.

As I am typing this, I am hearing Woodway PD transmitting on 155.955, their usual dispatch frequency. The scanner shows CT:100.0 and it is coming up as conventional. So, I might enter all of the listed frequencies & see what comes up.

Any help would be appreciated.

Ensnared · #2 (**permalink**) 11-16-2011, 11:02 AM

Here is a digital recording of the CC channel, 155.535 mhz. Please, tell me what type of system I am hearing. I have listened to many audio samples. I think this is a Motorola System, but I could be wrong.

Audio Project: Woodway Trunking Control Channel Audio Clip

texasemt13 · #3 (**permalink**) 11-16-2011, 11:07 AM

Ensnared you have a PSR-500 right?

If so, manually program a new trunking system and place that control channel in the first position. From there, select the new TSYS, and "Analyze" the control channel. This should allow it to tune the cc and display site information, system id and signal strength. We can get some more information from that.

Also, have pressed "Tune" and entered the control channel frequency? That will show you a NAC or CTCSS tone (further telling us if it's P25 or analog, or worse).

Ensnared · #4 (**permalink**) 11-16-2011, 11:13 AM

Quote:

Originally Posted by texasemt13

Ensnared you have a PSR-500 right?

If so, manually program a new trunking system and place that control channel in the first position. From there, select the new TSYS, and "Analyze" the control channel. This should allow it to tune the cc and display site information, system id and signal strength. We can get some more information from that.

Also, have pressed "Tune" and entered the control channel frequency? That will show you a NAC or CTCSS tone (further telling us if it's P25 or analog, or worse).

Yes, I have a PSR 500. Ok, I will attempt to do this. I have not attempted to manually program a TSY, but I will get out the manual out again. I sent you an audio sample of the CC sound.

I will get back with you shortly. Thanks.

texasemt13 · #5 (**permalink**) 11-16-2011, 11:16 AM

There is probably an easier way (if you read the manual), but I always add a new talkgroup and when it asks for the TSYS it corresponds with I create a new one (TSYS) at that point. That way if it tunes the control channel I instantly starting getting active talkgroups (thanks to control channel only trunking).

Ensnared · #6 (**permalink**) 11-16-2011, 11:18 AM

Quote:

Originally Posted by texasemt13

There is probably an easier way (if you read the manual), but I always add a new talkgroup and when it asks for the TSYS it corresponds with I create a new one (TSYS) at that point. That way if it tunes the control channel I instantly starting getting active talkgroups (thanks to control channel only trunking).

Did you hear the CC audio clip. Does it sound like Motorola?

texasemt13 · #7 (**permalink**) 11-16-2011, 11:21 AM

Quote:

Originally Posted by Ensnared

Did you hear the CC audio clip. Does it sound like Motorola?

I wouldn't know, I haven't compared CC noise in awhile.

I would hope it's not Trbo or Nexedge or OpenSky before anything else.

Ensnared · #8 (**permalink**) 11-16-2011, 11:29 AM

Some time back, I noticed a Woodway cop using laser on highway 84. Later, I asked a Woodway cop about this and he confirmed the existence of lasers being used. He proceeded to tell me about the department's technological advances & that they would be going to digital communications one day. I kept my mouth shut since I was not holding my scanner at the time.

So, since I heard Woodway transmitting on their old analog frequency, I am guessing this is analog trunking at this time. I thought the FCC DB would differentiate between analog and digital.

I am working on the programming. I will return in a few.

Ensnared · #9 (**permalink**) 11-16-2011, 12:24 PM

Quote:

Originally Posted by texasemt13

Ensnared you have a PSR-500 right?

If so, manually program a new trunking system and place that control channel in the first position. From there, select the new TSYS, and "Analyze" the control channel. This should allow it to tune the cc and display site information, system id and signal strength. We can get some more information from that.

Also, have pressed "Tune" and entered the control channel frequency? That will show you a NAC or CTCSS tone (further telling us if it's P25 or analog, or worse).

Here is what I am seeing after hitting the analyze soft key:

04% SID:_______S____
CT:____,____

It showed a TG of 14320 for a very brief period. I wonder if that was when an active TG was keyed in the system? When asked, I entered this as a MOT 800 system.

Ensnared · #10 (**permalink**) 11-16-2011, 12:37 PM

When I put this into scan mode, here is what I am seeing:
Scn1225 CONV p1D
DG 155.535
SRCH 155.535
Scan List 1
P25:481

Ensnared · #11 (**permalink**) 11-16-2011, 01:33 PM

I hope I am wrong, but when I listen to the CC for this system, it sounds like MotoTRBO. I visited this site after a listener suggested this possibility.

W2SJW - Radio Sounds

The worst case scenario is that this is a MotoTRBO system which has yet to be activated. I am still hearing Woodway on their old conventional dispatch frequency. This does not look good for those who monitor Woodway. But, I have made many mistakes in my life. Let's hope I am wrong about this.

texasemt13 · #12 (**permalink**) 11-16-2011, 03:34 PM

Quote:

Originally Posted by Ensnared

I thought the FCC DB would differentiate between analog and digital.

They do but you have to search the frequencies tab for the emission designators (and then decode these). I think RR has a wiki to help decode them.

texasemt13 · #13 (**permalink**) 11-16-2011, 03:39 PM

Ensnared,

Leave it in "analyze" like you had it in post #9 next time you get close to Woodway. You'll probably need a 70%+ better decode rate (as opposed to 4%) to get reliable information.

The P25 indicator in the scan list screen is actually a good thing, if it can be trusted. I'd leave it in "Auto" rather than "P25" (so it will decode analog and digital). To me it looks like it could be P25, the audio clip comparison does not sound similar to a Trbo CC, but pretty close to P25.

Ensnared · #14 (**permalink**) 11-16-2011, 04:20 PM

Quote:

Originally Posted by texasemt13

Ensnared,

Leave it in "analyze" like you had it in post #9 next time you get close to Woodway. You'll probably need a 70%+ better decode rate (as opposed to 4%) to get reliable information.

The P25 indicator in the scan list screen is actually a good thing, if it can be trusted. I'd leave it in "Auto" rather than "P25" (so it will decode analog and digital). To me it looks like it could be P25, the audio clip comparison does not sound similar to a Trbo CC, but pretty close to P25.

The only thing that does not a bit of sense is me being able to hear Woodway PD in conventional mode, analog.

If I programmed this system as a MOT 800, it would likely have an effect on the radios ability to discern the particulars of the system in question. If I were to program it as a P25 Auto, maybe could get a better signal.

By line of sight, I am less about 2-3 miles from the transmit tower. So, this tells me I have the system I might have the system programmed wrong. When this CC is compared with TxWarn or the Waco-McLennan county TSY, there is a big difference in signal strength.

So, you're also telling me this "analyze" functions like a frequency counter? That is, sometimes it is necessary to get closer to the transmit site to analyze the system?

texasemt13 · #15 (**permalink**) 11-16-2011, 08:43 PM

No, it's not a frequency counter, but it "analyzes" some of the data the control channel broadcasts (like SysID, Site ID, WACN and decode strength).

As is the case with new trunking systems, they might only have the control channel repeater up and transmitting, waiting on other equip or buildout.

Have you checked the emission designators yet? Are you going to make me go do it?

texasemt13 · #16 (**permalink**) 11-16-2011, 08:46 PM

They have:

11K2F3E: 2.5 kHz deviation FM "narrowband 12.5 kHz" analog voice
8K10F1E: P25 Phase I C4FM

Had you gone and looked, you'd know they're licensed for both! The search continues!

Program in two separate TSYSs, one as VHF and the other as P25 Auto.

Russell · #17 (**permalink**) 11-17-2011, 07:56 AM

I'm thinking mixed mode analog and digital (P25 Conventional) rather than trunked.

Ensnared · #18 (**permalink**) 11-17-2011, 11:09 AM

Quote:

Originally Posted by texasemt13

They have:

11K2F3E: 2.5 kHz deviation FM "narrowband 12.5 kHz" analog voice
8K10F1E: P25 Phase I C4FM

Had you gone and looked, you'd know they're licensed for both! The search continues!

Program in two separate TSYSs, one as VHF and the other as P25 Auto.

"Had I gone and looked?" I did go look and the FCC DB clearly stated, "trunked." As for this formula of emissions, I opened a page on this and read it. I was reviewing the process & trying to analyze the procedure, but I was derailed when I received a "heap error" which has not occurred since I bought the scanner and attempted to manually program it.

Since I exclusively use Win500 and not manual programming, this had to be reviewed as well. So, this is going to be a slow process for me. However, this is how I learn. I make notes in Word on any solutions I encounter. So, your help has not been wasted or taken for granted. I greatly appreciate your help & the help of others. Please, be patient.

texasemt13 · #19 (**permalink**) 11-17-2011, 11:25 AM

A heap error is because there is a talkgroup that is not associated with a TSYS.

It's easy to find with software, and not so easy without it. Good luck.

Ensnared · #20 (**permalink**) 11-17-2011, 12:09 PM

Quote:

Originally Posted by texasemt13

A heap error is because there is a talkgroup that is not associated with a TSYS.

It's easy to find with software, and not so easy without it. Good luck.

Yes, I found it easily with Win500. It used the unassigned button for the TGRG's not associated with TSY. Now, it is working well.

I searched for the emissions designator and found this information. http://www.comsearch.com/articles/emission.pdf

While reviewing the emissions page in RR, I found three emissions designators for the license. When I reviewed the Wiki page on emissions designators, I discovered that no calcuations were needed since someone had already done this. I may be complicating this more than needed.

Successful programming completed. Both TSY's were entered as: VHF and P25 auto. Let's see what happens.

Thanks for the help.