Southwest Regional Communication Center was an nxdn system, but has now joined the NTIRN as talkgroup SWR. My TRX-1 picked up the nxdn channels with no problem thru a download from the Radioreference data base. I have since downloaded every combination of SWR that I can think of and all I get is squelch break which indicates someone is transmitting, but I get no volume/audio at all. I know the scanner is capable of volume as the weather channel comes over just fine. Scanner Support from Whistler has been excellent, but so far we have been unsuccessful in our quest. Is anyone else capable of picking up NTIRN on your whistler and if so what is the secret to your success.
Unable to get volume on NTIRN channels
- Thread starter fits_51
- Start date
Looks like all the SWRCC TG's are TDMA, which that scanner can't decode.
South West Regional Comm Center
Cedar Hill, DeSoto, Duncanville| DEC | HEX | Mode | Alpha Tag | Description | Tag |
|---|---|---|---|---|---|
| 36003 | 8ca3 | T | SWR PD Disp 1 | SWR Police Dispatch 1 | Law Dispatch |
| 36004 | 8ca4 | T | SWR PD Disp 2 | SWR Police Dispatch 2 | Law Dispatch |
| 36005 | 8ca5 | TE | SWR PD Secure | SWR Police Secure | Law Tac |
| 36001 | 8ca1 | T | SWR FD Disp | SWR Fire Dispatch | Fire Dispatch |
| 36008 | 8ca8 | T | SWR Ops 1 | SWR Ops 1 | Multi-Tac |
| 36009 | 8ca9 | T | SWR Ops 2 | SWR Ops 2 | Multi-Tac |
| 36010 | 8caa | T | SWR Ops 3 | SWR Ops 3 | Multi-Tac |
| 36011 | 8cab | T | SWR Ops 4 | SWR Ops 4 | Multi-Tac |
| 36012 | 8cac | T | SWR Ops 5 | SWR Ops 5 | Multi-Tac |
| 36013 | 8cad | T | SWR Ops 6 | SWR Ops 6 | Multi-Tac |
| 36014 | 8cae | T | SWR Ops 7 | SWR Ops 7 | Multi-Tac |
| 36015 | 8caf | T | SWR Ops 8 | SWR Ops 8 | Multi-Tac |
| 36002 | 8ca2 | T | SWR EOC | SWR EOC | Emergency Ops |
| 36027 | 8cbb | TE | SWR Enc 36027 | encrypted | Multi-Tac |
| 36029 | 8cbd | TE | SWR Enc 36029 | encrypted | Multi-Tac |
| 36031 | 8cbf | T | SWR Event 1 | SWR Event 1 | Multi-Talk |
| 36081 | 8cf1 | T | SWR Event 2 | SWR Event 2 | Multi-Talk |
| 36040 | 8cc8 | T | CH Public Works | Cedar Hill Public Works | Public Works |
| 36043 | 8ccb | T | CH Parks 1 | Cedar Hill Parks Ops 1 | Public Works |
| 36044 | 8ccc | T | CH Parks 2 | Cedar Hill Parks Ops 2 | Public Works |
Crap! Disregard my post. The TRX-1 most assuredly does decode TDMA. I'm an idiot, I'm sorry.
tvengr
Well Known Member
OP has a TRX-1 which technically can decode TDMA. The problem may be simulcast distortion.
Actually, the TRX-1 can do P25 Phase II. What it can't do is cope with simulcast.
When the transition first started, moving Dallas & Dallas County from their conventional channels to NTIRN, I set up my TRX-1 to use a wildcard & record everything it picked up.
Over the time I had it parked on NTIRN, it recorded hundreds of audio files. But when I downloaded them & started to review the audio, all were useless, too garbled to provide anything of use.
Last edited:
Bingo. You get a cookie for the correct answer.
What site are you using? Be sure you have "Dallas Layer 1" not the Fort Worth "Layer 1". Check your squelch.
More importantly, what is the OPs approximate location. You need Dallas Layer 1 & Dallas Layer 2.
I have all 750 channels in one scan list. I get a word or two, or a few seconds of continuous broadcast, or a D2 and info screen, but nothing in the way of 100 %. I am in southern dallas county and all I want to do is pick up the SWR talk group which is detailed in the first of this thread.
At present, the SWRCC cities (Cedar Hill, Desoto, and Duncanville) might come across on either Dallas Layer 1 or Dallas Layer 2. Both of those are simulcast sites, so your reception would not be 'better or worse' if you only programmed the specific SWRCC talkgroups. Once everything settles down, and all cities & agencies have converted to NTIRN, Dallas Layer 1 should be primary for public safety talkgroups, with Dallas Layer 2 handling the various departments and agencies within the cities that are not part of public safety.
tvengr
Well Known Member
The Dallas Layer 1 site uses 700 MHz frequencies. For that site, go to the Site Options tab in TRX-1 EZ-Scan. Trunking Tables must be set to Auto Fill.
tvengr
Well Known Member
So much for that idea! Setting Trunking Tables to Standard will work for 800 MHz. For 700 MHz, you must use Auto Fill.
I tried to attach videos that demo what I am experiencing, but apparently a small video is still too big. I can get a partial transmission from some of the Dallas channels with audio, some I can understand, some every other word. And I can OCCASIONALLY see SWR PD1 which is the main channel I need, but no audio and no D2. I get a lot of squelch bars and a T and a D2 but no audio.
And thanks to all of you who are trying to help me out.
And thanks to all of you who are trying to help me out.
You've got quite a few more sites programmed, that you, likely, will not be able to receive in most of Dallas County. That in itself does not affect how you receive the site you need, but the scanner wastes a bit of time checking all these extra sites that are either out of range, or not of interest.
But the bottom line is still that the Dallas Layer 1 site, which is what you'll need for most all public safety talkgroups, is still simulcast.The frequencies for that site are using the state's license for 700MHz, so looking at the site map does not give the locations of the various sub-sites (transmit towers) for this site.
You can access the site map for Dallas Layer 2, which uses most (if not all) of the frequencies for the analog Dallas Local Government. I suspect, but have no way to confirm, that at least some of the 700MHz sites are co-located on the same towers as Layer 2. There were a couple of sites added (from what the old, analog, system used). Another site (not reflected on this map) is on license WNXM603, which includes 4100 W. Illinois, where DPD Southwest Patrol Division, as well as other city departments, are located.
You indicate that you are in southern Dallas County. That would put you somewhere between the site on the lower left corner and the site on the southeast side. Those two, plus the two sites in the downtown.Fair Park area,means that their signals would arrive at your scanner at varying times, out of sync from each other, That results in the Simulcast Distortion that you will find mentioned in a high proportion of threads here in the forums, regarding problems with monitoring various systems around the country. If you are very close to one of the sites (like a quarter mile or so), that very strong signal might be able to override the out of sync signals from other sites. From a fixed location, such as your home, you might be able to use a directional antenna, such as a yagi, aimed at one specific site. That way, it's signal will be much stronger than signals from towers not located in that direction. On the Simulcast Distortion page in the Wiki (linked above), there are a few other suggestions of things to try. One them might work, or maybe not, but you could at least try them. One thing you might try is, with the scanner sitting on your desk or a table, place a taller metal object, such as an aluminum baking pan next to the scanner, and try it on various sides of the scanner. In some cases. this may null out out sites, or at least reduce their signals, leaving the scanner receiving only one site.
Most of these suggestions would be impossible, nor practical, when you are out driving around in your vehicle.
I am told that our three existing towers, physically located in Duncanville and Cedar Hill and DeSoto are being patched in to this system. I have no way of verifying if this is true now and/or planned on. Does anyone have a work around for the synchronization prob.
I l/o all trunking except dallas layers 1 and 2. I also l/o all channels within NTIRN except the tgrp SWR. I get lots of signal strength bars, and a black back ground S constantly and an actual squelch break with a tad of conversation on some of the swr channels. The channels are there, I just can't get them to behave normally. With what you responders have said, I'm hoping it might be the sychronization thing as I do get partial transmissions.
I'm around the same area, and my TRX-2 does poorly on this system. The only way it might work ok, is with a directional antenna pointed at the far south west corner tower that is closer to me. I just haven't messed with it yet, seeing how I am using my Unication G5 to monitor all the SWR talkgroups. You might have to end up getting a Uniden SDS100 or Unication G5 if you need a portable. The only thing about the Unication G5 is there are limitations, but I knew that when I got mine.
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