New SDR hobbiest, question about the Aliant TMRS

[rob79]

Hi everyone, how's it going?

So like the title says I'm new to amateur radio in general and recently picked up one of those cheap RTLSDR dongles. Been having lots of fun with it and have been experimenting with using it as a scanner.

I have no problems getting it to work with the trunk radio system here in NS, but there are some talk groups (I think that's the right term - they show as "Target ID's" in the software I'm using) that aren't in the database here on radioreference.com.

One that I see *constantly* is 7184. Every few minutes there is a join/call from that target ID. Does anyone know what it is? Right now (because of my setup) I can only listen in on the digital signals (you need two RTLSDR dongles to be able to listen in on analogue - I have a second one coming in the mail). This target ID is always calling on analogue so I can't try to ID it just by listening in.

Thanks in advance for any info about 7184 (or any tips in general regarding radio listening in NS)!

If anyone is curious about how to use the RTLSDR dongles (can literally set up a trunk-tracking scanner that will rival an $800 Uniden for $30, listen in on anything from 22Mhz-2200Mhz, amateur satellite tracking, ADS-B/ACARS, etc) I'd be happy to answer any questions (although I'm sure there are people here that know a lot more than me).

Take care!

 

[darrylcn]

Hi Rob, is there a guide you used, or do you have a list of the specific files and versions you used? I messed with this a bit but had no audio decode. Did you use 2 dongles or 1? Ive got a spare and a PC that was picked up just for this function but it's not used for now because I didn't have any luck.

 

[EdwinAnthony]

Hey there Rob, Yes, I'm very curious as to your equipment and complete trunktracking setup!

 

[rob79]

Hey darrylcn / EdwinAnthony!

EdwinAnthony - Regarding the equipment you need for what I have set up it's a DVB-T stick using the RTL2832U chipset. The one I have uses a secondary chip (R820T) that gives it a very broad frequency range (22-2200 MHz). You can also get ones that use a different secondary chip (E4000) that is basically the same. For digital trunk tracking you only need one of these sticks, if you want to be able to listen in to both analogue and digital you need two of these sticks. You can buy them on eBay for ~$10-$15 each. I only have one at the moment but already ordered a second one, it's just taking forever to arrive .

darrylcn - As for software I'm using Windows so it's a combination of Unitrunker, SDR#, VB-Audio-Cable, and DSDPlus. As for finding a "guide" online - it's not as straight forward as one would expect. I used a bunch of different guides (randomly googling "rtlsdr trunk tracking") to finally get a working solution. Bits from one guide would work, bits from another guide, etc. I don't have a specific link I can share b/c like i said - I got the info from all over the place.

A few pieces of advice: On windows don't use the "DSD+Cygwin" combo many of the guides suggest, instead look for DSDPlus. The original DSD was a Linux application and required the Cygwin emulator to work on Windows, DSDPlus is a native windows app, performs much better, and is much easier to install/use. The version I'm using is v1.023 - I'm not sure if that's the newest one but it's working well.

I'm using the latest version of Unitrunker from their website. Setting up Unitrunker is a bit weird, if you get this far ask me again and I'll just explain exactly how I got it to work.

Finally, the latest version of SDR# can't be connected to Unitrunker (no trunk tracking plugin) so you have to use an older version that supports trunk tracking. Again, it's all about finding a guide that explains how to use the trunking plugin.

Sorry I can't be more help but it was a lot of trial-and-error to get it working. I will say it works *beautifully* now that I've got it all set up and adding the second dongle for analogue reception will be a cinch once I get it.

 

[hfxChris]

Rob where are you located? Sounds like you've discovered a talkgroup that has not yet been identified. More than likely a commercial/business user.

 

[darrylcn]

Good thinking Chris. Also I have noticed that over the last 24 hrs Geizers has taken to its old 'static for 7 seconds on a tgrp regardless of whether it's in use' tricks. I temporarily deleted it from my scanner and have been relying on Sackville till it's fixed again. The police seem to be having some issue with radio traffic getting through, pretty sure this is the cause. Hopefully it's fixed soon. Definitely a safety hazard.

 

[kb3isq]

What equipment is needed to use as a scanner IE: PC, software, etc?

 

[rob79]

Rob where are you located? Sounds like you've discovered a talkgroup that has not yet been identified. More than likely a commercial/business user.

Hey hfxChris - first thx for filling out so many of the talkgroups - I noticed your name connected a lot with the TMRS here.

I'm located in northern Guysborough County near Cape Breton. Not a lot of activity on the radio system here since it's such a rural area but this 7184 talkgroup is one of the MOST active by far (except for EMS). Unfortunatly since I'm still waiting for my 2nd RTLSDR dongle I'm not able to listen in on it since it's analogue (waiting for shipping from China...will probably be another month before it arrives).

The only reference I've seen to this talkgroup anywhere online was on the site I've linked below and it's labeled as "unknown". I've been googling it off and on for the better part of 2 weeks now and have no leads...

http://www.marscan.com/tmridbynumber.htm

-Rob.

 

[darrylcn]

You'll need a PC/Laptop, an SDR Dongle like this one:
NooElec - NooElec NESDR Mini SDR & DVB-T USB Stick (R820T) w/ Antenna and Remote Control - Software Defined Radio

... and an included antenna. The software part is what we're trying to figure out based on Rob's experience. I can't speak for others here but I've been "this" close without getting a good scanner alternative so far.

 

[rob79]

By the way folks - sorry for the delay in my replies. I was replying right away but since I'm a new user I have to wait for a moderator to approve my posts . If you ask something and you don't hear back from me right away that's the reason. Not sure how long it will be before I can just post freely.

 

[darrylcn]

Hopefully not long Rob, I think we're looking forward to hearing how you managed to decode things without issue. I know I am.

 

[rob79]

Hopefully not long Rob, I think we're looking forward to hearing how you managed to decode things without issue. I know I am.

It's strange that my explanation showed up before my *actual* post about the topic (which I wrote ~6 hours ago) LOL. I'll wait a little bit longer and see if it gets approved, if not I'll just write it out again. HINT: It boils down to using DSDPlus (not DSD and Cygwin) on Windows, Unitrunker (latest version), and an older version of SDR#. There is no real guide I followed, it was all trial and error cobbled together from a bunch of different sources but it works brilliantly.

 

[rob79]

Oh jeez, my bad. My other posts did get approved and showed up further up the thread . Scroll up and everything I wrote out is in the appropriate place in the timeline of this discussion.

 

[rob79]

Hey darrylcn - look further up the thread, my other posts got approved and appear above.

 

[hfxChris]

Hey hfxChris - first thx for filling out so many of the talkgroups - I noticed your name connected a lot with the TMRS here.

I'm located in northern Guysborough County near Cape Breton. Not a lot of activity on the radio system here since it's such a rural area but this 7184 talkgroup is one of the MOST active by far (except for EMS). Unfortunatly since I'm still waiting for my 2nd RTLSDR dongle I'm not able to listen in on it since it's analogue (waiting for shipping from China...will probably be another month before it arrives).

Well don't thank me too much, the database on this site is entirely user contributed, all I do is format it so that it meets radioreference's requirements, the actual content I've contributed is relatively small! Definitely a community effort, so if you ever do identify 7184 be sure to submit the information and I'll add it!

A good way I find to know if it's a commercial user or not, is do you see this talkgroup pop up in the evenings. Most (obviously not all) commercial talkgroups are extremely active during business hours and go mostly silent in the evenings and weekends. Then again a lot of non-emergency government users on the TMR also keep bankers hours, so that's not a guarantee.

 

[darrylcn]

Hi Chris, I looked yesterday but didn't find any info here on the new TMR. I assume as it trickles in that will pop up but so far there's no list of CCs talkgroups or sites?

 

[hfxChris]

Correct; control channels are not yet known. Marscan has a list of sites on his website Bill's Site but until something becomes active (even just in testing) and we start to figure out and discover some of the frequencies for the sites, I really can't add anything to the database.

 

[darrylcn]

Got it thanks. I was just wondering today if they're going to have Pri/Sec divisions' talkgroups still.

 

[hfxChris]

I would imagine most agencies will keep the same talkgroup "names" as they do now, mostly because they're just used to it. So I would bet you'll still see HRP have east, west and central both primary and secondary talkgroups, HRM fire will probably just have a single dispatch TG and maybe 10 or so ops TGs, none of these old rural talkgroups. EHS will probably keep the same talkgroups, again it's what they're used to even if I find it confusing remembering which region is north 1 and which is north 2...

 

[darrylcn]

Ah yeah makes sense. People were switching back and forth today and it was so routine it wouldn't make sense to have a new way of operating.