Help programming DMR

[jackmail226]

I have a BCD 536 with DMR but I'm in an area where 95% of police, Fire and government are full-time encrypted.

I have the Ham Repeaters, Forest Service and a few other things programmed but I’d like to discover more activity in my area.

I’m seeing lots of DMR activity on the scanner that is not in the database. Some of it I can receive but some has full scale signal but no audio.

I'm hoping someone help me a little as I'd like to eventually share what I've found with others including Radio Reference.

My question is this:

I have found several channels that have DMR activity with CAP showing on the display, as I see the signal meter at full scale I hear no voice at all.

I’ve programed them in the scanner I using ID “search” to on and Color Code search to on as well.

Are there any other “wildcard” parameters I am missing to allow audio to come through then the ID search and CC search parameters I've turned on?

For the purpose of hearing some voice --- does it matter how I program in the scanner MOTOtrbo, Conventional, One Frequency DMR - just to hear some voice traffic?

I know I will eventually need the LCN numbers as well but is LCN necessary to at least hear a little audio on the CAP system signal that shows up on the display of the BCD536?

Any assistance appreciated

 

[RoninJoliet]

On my 325p2 I had to choose DMR Mototrbo trunking and install the lcn each freqys to hear voice and see he IDs

 

[Whiskey3JMC]

I have found several channels that have DMR activity with CAP showing on the display, as I see the signal meter at full scale I hear no voice at all.
...I know I will eventually need the LCN numbers as well but is LCN necessary to at least hear a little audio on the CAP system signal that shows up on the display of the BCD536?

If you hear or see a data burst every few seconds then you've landed on a rest channel (similar to a control channel) and may not hear any voice activity on this frequency until another frequency on the same repeater becomes a rest channel. Do an FCC search on this frequency to identify potential licenses within listening range to you and find out additional frequency(ies) you may be missing. If you become an RR premium subscriber you can use Radioreference's FCC data search tool which is easier to use than the FCC ULS page. I also use maprad.io which gives you more ways to query a search in addition to frequency (license type, emissions type, etc) and a nice map view to see potential licenses in your area. If you're lucky you may hear the repeater ID its callsign & this is when it pays to know some morse code (at least know the numbers) so you can match it with the callsign on the license. If you manage to capture a talkgroup or two on more than one frequency on the same license then you've likely identified the correct station. Once you've confirmed which frequency(ies) on the license are active then you'll need to run LCN finder to determine the correct LCNs so the system can be tracked properly. It helps to enter correct color code(s) to avoid interference from other stations who may be using DMR on the same frequency but with a different CC. Some CAP+ systems only utilize one frequency.

For the purpose of hearing some voice --- does it matter how I program in the scanner MOTOtrbo, Conventional, One Frequency DMR - just to hear some voice traffic?

With regards to CAP+ this should be programmed in as a MOTOTRBO trunked system once all active frequencies on the license are indentified (the same applies to CON+ & DT3. DMR One-frequency is just that: One frequency, two slots, one talkgroup assigned per slot

DMR and MOTOTRBO Tips for the BCDx36HP and SDS Scanners - The RadioReference Wiki

wiki.radioreference.com

 

[jackmail226]

Thanks for all the information and the links. appreciated.

Until I identify the system and all it's frequencies, does the frequency I have -- have to be entered as a MOTOtrbo system or can the frequency I know be entered temporarily as a One-Frequency, or conventional - just to be able to hear some voices...

I'm looking for a way to at least start to hear some traffic which may also give me a clue to what company I am listening to. I'm going to play with the FCC database too...

 

[Whiskey3JMC]

Until I identify the system and all it's frequencies, does the frequency I have -- have to be entered as a MOTOtrbo system or can the frequency I know be entered temporarily as a One-Frequency, or conventional - just to be able to hear some voices...

Please re-read my final paragraph in Post #3. Adding to that, you can certainly program them as conventional but you're going to get annoying stoppages every time the active rest channel is encountered. Temporarily avoiding said rest channel may be a viable workaround if you want to check for voice activity on the other frequencies but if the rest channel changes you'll have to repeat the process. Another alternative is using a software-defined radio paired with DSD+ to check each frequency for activity & similar talkgroup(s) & gather channel IDs but that's a topic for a whole different forum

 

[jackmail226]

I only have one channel at this moment so I guess I'll have to search the FCC Database and perhaps subscribe here to be able to figure out what other frequencies are part of the license.

If these repeaters ID in CW, I can probably copy that unless it's super fast. I'm sure knowing the call sign would make the whole research part easier!

I have several CAP+ frequencies coming up on the BCD536 so I may have to do lots of research.

 

[Whiskey3JMC]

I have several CAP+ frequencies coming up on the BCD536 so I may have to do lots of research.

That's what makes the hobby so fun

 

[Ubbe]

Until I identify the system and all it's frequencies, does the frequency I have -- have to be entered as a MOTOtrbo system or can the frequency I know be entered temporarily as a One-Frequency, or conventional - just to be able to hear some voices...

Yes, program unknown DMR frequencies as OneFrequency and it will only stop scan on conversations and not on the idle data transmissions. Trunked systems can always be monitored as conventional or as OneFrequency. Put each frequency in its own site so that you can name tag that site and make the frequency easier to recognize.

If you have recording enabled you can then copy the files to your PC and easy analyze the result using Universal Scanner Audio Player.

/Ubbe

 

[dave3825]

I only have one channel at this moment so I guess I'll have to search the FCC Database

When you do, take note of Radio Service that shown on top right of license. It, if correct, will tell you if its trunked or conventional.

 

[Whiskey3JMC]

When you do, take note of Radio Service that shown on top right of license. It, if correct, will tell you if its trunked or conventional.

There are exceptions to this rule, particularly with single-site TRBO systems. Take WQHT518 for example. Radio service shows "IG" on the license but system is CAP+

Foulkeways at Gywnedd Trunking System, Gywnedd, Pennsylvania

Foulkeways at Gywnedd Trunking System Profile

www.radioreference.com

 

[jackmail226]

When looking at the Frequency (in the FCC Database) I often see emission type. Is this a good way to identify what flavor of "digital" is being used as well?

 

[jackmail226]

Also, is it a requirement that business systems have CW Id active on their repeaters and/or trunked systems? I seem not to hear much CW Id's but have been away for last week, not playing much radio...

 

[dave3825]

I don't know about the cw stuff but I do know the emissions are not always correct on the FCC licenses. I have been doing this long enough to know what type of signal I am hearing. You can usually verify what they are hearing by going to the signal wiki..

Next Generation Digital Narrowband (NXDN) - Signal Identification Wiki

NXDN is a digital narrowband trunked radio protocol used in commercial, business & industry, transport and Public Safety professional radio systems.

www.sigidwiki.com

Digital Mobile Radio (DMR) - Signal Identification Wiki

Digital Mobile Radio (DMR) is an open digital mobile radio standard defined by ETSI and used in commercial products around the world. Mostly used by private network and local police, can be encrypted. Used in MOTOTRBO products.

www.sigidwiki.com

Project 25 (P25) - Signal Identification Wiki

Project 25 (P25 or APCO-25) is a trunked radio standard developed by The Association of Public Safety Communications Officials International (APCO-25) for use with public safety organizations around the world.

www.sigidwiki.com

Motorola Type II - Signal Identification Wiki

Radio trunking control channel.

www.sigidwiki.com

 

[jackmail226]

that is a pretty cool site,. Thanks