Multi-Net Listening

[mlevin]

I've heard there's a computer program that with two scanners can track multi-net systems. Does anyone have info that could get me pointed in the right direction.

Is it possible to buy a multi-net radio and get it programmed?

 

[pro92b]

The program is at http://www.radioreference.com/modules.php?name=Downloads&d_op=getit&lid=74

You can find radios on Ebay but getting them programmed is a big problem. Each MultiNet system has a unique key and only the system administrator and EF Johnson have the key. The radio will not even receive the system without the key.

 

[mlevin]

What kind of scanners would I need to do this? Could I just use any scanner? I'm assuming I'll need a discriminator tap and data slicer. How would I go about getting one installed?

 

[ka3jjz]

As I understand it, a standard data slicer won't work; one has to be constructed. We have the schematic on our wiki...

http://wiki.radioreference.com/images/c/cd/LTRDicer1.png

Last I heard - and I could be wrong here - Eric C. was working on a simpler slicer design. I believe that most any scanner that can be tapped would work.

How to get a tap installed? A couple of folks are doing this; the Radio Doctor might be able to (he's in Virginia), that fellow that sells the 2 level data slicers and G&G I think can also do it (but his lead time is rather long...)

73s Mike

[edit] Here are the URLs for all of those items I mentioned above...

http://www.a1rd.com/

http://www.iinc.com/ggcomm/index.html

http://www.dataslicers.com/tapservice.htm

 

[mlevin]

Thanks for the leads Mike.

 

[MIN003]

If you can get a Uniden BC780 you don't need the voice filter if you do the instructions for "Slicer Tap A" - this taps direct into the built-in slicer in the scanner. This simplifies the connection quite a bit.

A basic 2-level slicer is not to hard to make, you should be able to get the parts at Radio Smack. It's been a while since I made mine, but I don't recall it being too painful.

There was a posting on the trunker yahoo thread that a 2-level slicer might not even be needed if you connect to Tap A. The poster thought that a direct connection from the Tap A point to a 9 pin PC cable could work. I haven't tried it yet, but would make the process even easier.

You should be able to find a Uniden 780 reasonably cheap on Ebay or a local pawn shop, they are a few generations old now.

 

[tolley]

What Multinet system are you trying to monitor Chester County?

 

[mlevin]

Waterbury, CT

 

[Avenger44]

Chester County Is Useing a Multi-Net II 800 MHz Trunked System . Nextel / Sprint , is going to be Buying New Radios for Chester County for the EF Johnson System . They will then be able to Re-Tune the Trunked Repeater Sites and Be able to Tx on 700 MHz and Rx on 812 to 815 MHz . the New Radios will also allow them to Program there Radios with othere Trunked System , Like Montgomey County 800 MHz Astro Trunked System Along with the EFJ System that Chesco Has .

Steve.

 

[Avenger44]

I Also have Modified Software for Programming the EF Johnson 8615 800 MHz LTR Mobile that would Allow it to Rx Multi-Net , And Multi-Net II Trunked Systems Like Chester County , But it will not be able to Tx . Don't Need System Key for it to Just Rx . Works Grate . At Least you can Hear Whats going on on Both Police and Fire .....

Steve.

 

[ctrabs74]

There is, of course, the option of programming in all the freqs in conventional mode, as I have with my 396 (and had done previously in my Pro-95). I can't figure out which TG is active, but at least I'm hearing some xmits instead of dead silence.

 

[Avenger44]

There is, of course, the option of programming in all the freqs in conventional mode, as I have with my 396 (and had done previously in my Pro-95). I can't figure out which TG is active, but at least I'm hearing some xmits instead of dead silence.

The West TG's are the Most Active . in the county .

Steve.

 

[bpckty1]

When programming an LTR Multinet to a scanner, such as the BC396 and BC246, does one program it as LTR, Motorola, or some other method? I will not be programming from a computer, just the old fashioned manual way. The talkgroups shown on RRDB, Bay City - Matagorda County, TX, for example, appear to be Motorola, 4 digits, not LTR, 6 digits.

 

[ctrabs74]

When programming an LTR Multinet to a scanner, such as the BC396 and BC246, does one program it as LTR, Motorola, or some other method? I will not be programming from a computer, just the old fashioned manual way. The talkgroups shown on RRDB, Bay City - Matagorda County, TX, for example, appear to be Motorola, 4 digits, not LTR, 6 digits.

Simply enter the frequencies in the LCN listed and program it in conventional format. That's as good as you're going to get with a commercial scanner. You may want to consider locking out the control channel, as most of the traffic on that particular frequency will be static or other sub-audible noise when there's voice traffic on other channels.

 

[thadood]

Simply enter the frequencies in the LCN listed and program it in conventional format. That's as good as you're going to get with a commercial scanner. You may want to consider locking out the control channel, as most of the traffic on that particular frequency will be static or other sub-audible noise when there's voice traffic on other channels.

i feel compelled to comment on this thread considering im the one who's been decoding the matagorda county LTR MultiNet system. i didnt program all the frequencies into 1 single scanner for a couple of reasons 1. a dedicated scanner is needed to monitor the status channel on the system , in my case the status channel is 866.675 which also has talkgroup voice transmissions on it regularly, 2. a second scanner dedicated to monitoring 867.175 because the frequency hangs open when there is a voice transmission on 867.825 and 868.7125, and a 3rd scanner dedicated to scanning all of the other LTR MultiNet frequencies aswell as any VHF freqs. as for the talkgroup updates in the DB the admins screwed up, when i submitted the information i submitted it as EXAMPLE "2-200 02c8 BCPD Primary". 2-200 02c8 is how LTR Trunker shows it before Text tagging. ive tried different methods over the years for following MultiNet with conventional scanning and the most efficient gurantee'd way is to use 3 scanners and LTR Trunker.

 

[bpckty1]

Thanx to both of you for the info.

Just curious, does the 2-200 translate to 0-02-200 in LTR speak?

 

[WayneH]

LTR and Multi-Net trunking are the same in digital signaling form but the bits used to represent groups, radios, etc are completely different. There are no scanners that successfully track Multi-Net trunking.

 

[DaveNF2G]

ive tried different methods over the years for following MultiNet with conventional scanning and the most efficient gurantee'd way is to use 3 scanners and LTR Trunker.

If you're using LTRTrunker, then you only need two scanners. I use it with a BC-235 (w/discriminator tap) and BC-296D (voice scanner).

Another caveat for LTRTrunker, in case anyone has missed it, is that you need a slicer with a low-pass filter to keep voice frequencies from confusing the program.