NTIRN
- Thread starter mvfa25
- Start date
Did you program it with software? If so, which program?
Steve i am using Free scan software v 2.18-bata6, here is the file i made
I can't send the file in the free scan format but here is a screen shot
Attachments
Open Windows Explorer (called File Explorer on some versions of Windows).
Got to the folder where you saved the file.
<Right><Click> on the file. You'll see a pop-up menu like this:
If you send it to a zip (compressed) file, then you can attach the zipped file to a post.
Also, where in Arlington are you (roughly, not your exact address)? Central Arlington, South Arlington (south of I-20?)? Maybe give us a thing to look for, like a nearby shopping center, or highway (or major roads) intersection.
Depending on your location, you might be getting hammered, on Johnson County by Simulcast.
That's also a possibility for Grand Prairie.
For Dallas, you should include both the Dallas Layer 1 & Dallas Layer 2 sites.
Depending on your location, you might be getting hammered, on Johnson County by Simulcast.
That's also a possibility for Grand Prairie.
For Dallas, you should include both the Dallas Layer 1 & Dallas Layer 2 sites.
i am south of 20 off 287 and turner warnell rd Arlington mansfield line
Let's take these one at a time:
Johnson County
Here is the site map for the Johnson County site. That wiggly X on the map is your approximate location. (I looked up Turner Warrell on Google maps.) The mapping program used for the site maps here on RadioReference don't have the flexibility to mark locations. So, I copied it to the clipboard, then edited it in Paint to add your approximate location.
The blue balloon markers are the transmitter locations (sub-sites) for the Johnson County Simulcast site. You are at varying distances from the Alvarado, Burleson, & Cleburne locations. So, signals from those sites arrive at your location just enough out of sync to hammer your scanner's ability to decode the transmissions. There is a more complete discussion of Simulcast Distortion in the Wiki.
Simulcast digital distortion - The RadioReference Wiki
Here is the site map for Grand Prairie, which is also simulcast.
You might have a simulcast problem there as well, but I suspect it's a different issue. I'm in Dallas, southwest of Downtown Dallas. Even though I'm less than ten miles from Grand Prairie, I can't up their site at home. On the older, Motorola Type II system, I had no problems hearing them; I could get Arlington as well. Now, I can't get either one.
Part of my problem is that ridge-line that runs SW to NE along a good bit of the Dallas-Grand Prairie border. So, Grand Prairie's transmit sites are 'below the horizon' to my west, meaning I don't get either system at home now.
But there is another problem with GP. Back when they submitted an updated request to change their existing sites to be licensed for using P25 Phase II. Looking in the notes on their FCC license request, there were several comments of interest. One of their old Moto frequencies interfered with Garland's (then) Moto Type II system. Grand Prairie said, in their request, that to eliminate, or at least reduce the interference, that they would do three things:
Reduce the power used on their sites.
Move the antennas lower on their towers.
And, refocus their antennas to concentrate coverage in their jurisdiction (city limits).
I think that last item, focusing the coverage, is a significant part of why I cannot hear their system now from home. Not too long after the updates & changes were made, and Grand Prairie switched to Phase II, I went to a appliance store in GP on their Main St. While actually in the city, I had no problems receiving them. If you are somewhat familiar with the area, you know that Main St. in GP feeds into what Dallas notes as Davis Blvd. by the time you reach Loop 12. Well, at Loop 12 & Davis, I could still hear them. But after I went up Chalk Hill, and got to the Davis/Cockrell Hill Rd intersection, I lost them completely. What you might do, on Grand Prairie, is to set the scanner on hold while it is scanning your Grand Prairie system. Look in the upper right corner of the display & see if there are any signal strength bars.
Are you using the supplied antenna fully or partly extended? For the frequencies used by these systems, it should be fully collapsed & vertical. you might also consider a gain antenna for 700/800MHz bands.
Now, let's look at Dallas.
Looking at your file, I see that you only have the Dallas Layer 1 site (700MHx frequencies) programmed. I know that all the discussion is that Public Safety will be on Layer 1, with all other Dallas County area traffic on Layer 2.
Well. that may be the intention, but at present, that is not happening. I have one of my 436HPs set to log and record all activity on NTIRN in Dallas County. I periodically copy those to my laptop, then look for new, unknown talkgroups, as well as activity on the current Dallas TGIDs. For the time period of 08/08 to 8/08, there were 434 transmissions captured for Dallas Fire 1, TGID 32001. Of those, 14 were on Layer 1 (which is what you have programmed) and the rest on Layer 2 (which is not programmed). For Dallas Southwest Patrol (I am in that area), I logged 518 transmissions. Of those, 25 were on Layer 1, the rest on Layer 2.
From comments I've seen posted, as well as some other contacts, the signal coverage seems to be strong enough that you should hear some of the traffic.
Try the file I attached. I simply added Dallas Layer 2. You were missing two frequencies on Dallas Layer 1, but neither were control channels, so that should not have mattered. I did not change anything on your Arlington, Johnson, or Mansfield systems. Extract the file & open it in FreeSCAN, then load it to your scanner & see if any improvement on Dallas. The Layer 1 frequencies are using the state's license, so we do not have specific locations of the individual sub-sites. Layer 2 sites are documented:
The closest Layer 2 site, to you, is on the edge of that ridge-line, overlooking
Check your signal strength on Grand Prairie. If the signal is strong, then simulcast may be a problem there as well. It is a simulcast site.
Attachments
Not possible to listen to Dallas. They are running tdma. The scanner cant listen to them. Just who is using digital on the network.
Some of Johnson County is running encrypted also.
He has a 996P2, which can decode it, if simulcast doesn't prevent it at his location. Mine works ok for me in NE Tarrant county to hear Dallas.
For those who haven't had to deal with simulcast distortion, Captain Obvious says ... Simulcast distortion genera;;y affects only those within simulcast areas.
Inside Dallas (and Fort Worth, etc.) simulcast distortion is a major factor. However, if you're attempting to monitor either Dallas layer from outside Dallas (from far enough away, like Tarrant County) then simulcast distortion is less of a factor. When Plano PAWM went to P25, folks in NE Tarrant County had very little problem hearing Plano, but inside Plano it was a major issue. The SDS models obviously handle distortion much better within such areas. In other words, if you're trying to monitor Dallas with a BCD996P2 from say McKinney, then simulcast distortion may not impact you at all.
Of course, YMMV.
Inside Dallas (and Fort Worth, etc.) simulcast distortion is a major factor. However, if you're attempting to monitor either Dallas layer from outside Dallas (from far enough away, like Tarrant County) then simulcast distortion is less of a factor. When Plano PAWM went to P25, folks in NE Tarrant County had very little problem hearing Plano, but inside Plano it was a major issue. The SDS models obviously handle distortion much better within such areas. In other words, if you're trying to monitor Dallas with a BCD996P2 from say McKinney, then simulcast distortion may not impact you at all.
Of course, YMMV.
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Very well said @Russell
My SDS100 works great IN dallas and my 436 not so much. But out at work in south eastern collin county the 436 starts to work much better.
I also have better decode on the 436 IN dallas when monitoring the Layer 2 800mhz side of dallas. But that is due to the 800 having less sites. But either way the SDS100 sounds great all the time.
My SDS100 works great IN dallas and my 436 not so much. But out at work in south eastern collin county the 436 starts to work much better.
I also have better decode on the 436 IN dallas when monitoring the Layer 2 800mhz side of dallas. But that is due to the 800 having less sites. But either way the SDS100 sounds great all the time.
That is not true for all simulcast sites
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