Android and Ham Radio

Frdmskr

Adventurer
How does the DV4Mini license their DMR implementation? I just feel like we should be able to homebrew this stuff at this point. :)

Or is it just a matter of putting an AMBE chip on a breakout board and the rest is already open source?

DMR is an open standard. Mototrbo and Hytera implant that standard with extra whizbang features on top of that. In contrast P25 I believe, while a standard, is somewhat proprietary.


Sent from my iPhone using Tapatalk
 

Frdmskr

Adventurer
How does the DV4Mini license their DMR implementation? I just feel like we should be able to homebrew this stuff at this point. :)
I think the only part that is really proprietary is DVSI's AMBE voice codec, which is used in most (maybe all?) digital systems. I'm not familiar with the DV4Mini but I assume it's either using those parts or has reversed engineered patented & copyright IP. Everything else is somewhere between open source and freely licensed from JARL, Yaesu, etc. The DMR protocol is an ETSI standard.

http://www.etsi.org/technologies-clusters/technologies/digital-mobile-radio

Motorola's MOTOTRBO is an extension of DMR, which is what most commercial surplus radios use. For example, I still have VXD radios, which are repackaged Motorola XPR models. Motorola added the IP layer to interconnect repeaters, trunking and some privacy stuff.

From a ham user standpoint the encryption stuff isn't legal anyway. The fundamental part, time slots, framing, packet definitions, that's all ETSI standards.

There's a global Motorola-based (using C-Bridges to interconnect) amateur network called DMR-MARC, which was what started it all and still is the framework for talkgroups and the database of user IDs. And if I understand it correctly, the IP Site Connect has been worked around using Brandmeister. So it's really just the AMBE stuff that's closed.

And why Yaesu decided to use it when that could have been the *one* thing they could have done differently is beyond me. But then I can't say how difficult it is to develop a new codec that works as well while also being different enough not to infringe on DVSI, so it may not be easily done.

The universe wonders what Yaesu was thinking. Basically they created a Phase 1 P25 system for hams.


Sent from my iPhone using Tapatalk
 

DaveInDenver

Middle Income Semi-Redneck
Icom doesn’t do DMR they do NXDN. Kenwood does DMR on the commercial side. Yaesu not sure because they were/are affiliated with Mototola i think.
Vertex Standard is owned by Motorola but Yaesu never was. When Vertex Standard was bought they spun off Yaesu back to a stand alone company. Vertex is now pretty much defunct, I think Motorola finally renamed it Motorola Solutions. They stopped supporting my VXD radios a long time ago.

NXDN was jointly developed by Icom and Kenwood. Kenwood calls it NEXEDGE and Icom IDAS. Icom sells NXDN and P25 radios (actually most companies sell P25 radios because that's what most public services use). DMR and NXDN are sold for business and industrial radios mostly.

Kenwood does all of them, DMR, P25 and NXDN. For example the NX-5000 multi-protocol radios.

http://comms.kenwood.com/special/nx_5000/

But like I say, what a charlie-foxtrot mess of competition.
 
Last edited:

Frdmskr

Adventurer
Icom doesn’t do DMR they do NXDN. Kenwood does DMR on the commercial side. Yaesu not sure because they were/are affiliated with Mototola i think.
Vertex Standard is owned by Motorola but Yaesu never was. When Vertex Standard was bought they spun off Yaesu back to a stand alone company. Vertex is now pretty much defunk, I think Motorola finally renamed it Motorola Solutions. They stopped supporting my VXD radios a long time ago.

NXDN was jointly developed by Icom and Kenwood. Kenwood calls it NEXEDGE and Icom IDAS. Icom sells NXDN and P25 radios (actually most companies sell P25 radios because that's what most public services use). DMR and NXDN are sold for business and industrial radios mostly.

Kenwood does all of them, DMR, P25 and NXDN. For example the NX-5000 multi-protocol radios.

http://comms.kenwood.com/special/nx_5000/

But like I say, what a charlie-foxtrot mess of competition.

Yeah because you go overseas and you add in Tetra!


Sent from my iPhone using Tapatalk
 
Picked one up recently too, Planning to use it with a Baofeng HT for APRS. So far having trouble getting it to work. Actually, I don't think it's the Mobilinkd with the problem. I think the problem is with the Baofeng(s) not receiving APRS transmissions. I have 2 different ones and neither seem to recive anything. Squelch is turned down all the way, have tried it at different levels and still nothing is coming through. I have checked this standing right next to my D710G in the truck which is receiving APRS transmissions the whole time. I understand the squelch on these cheap radios may not open fast enough, but they don't seem to pick up anything. Voice transmissions come over fine
 

prerunner1982

Adventurer
Picked one up recently too, Planning to use it with a Baofeng HT for APRS. So far having trouble getting it to work. Actually, I don't think it's the Mobilinkd with the problem. I think the problem is with the Baofeng(s) not receiving APRS transmissions. I have 2 different ones and neither seem to recive anything. Squelch is turned down all the way, have tried it at different levels and still nothing is coming through. I have checked this standing right next to my D710G in the truck which is receiving APRS transmissions the whole time. I understand the squelch on these cheap radios may not open fast enough, but they don't seem to pick up anything. Voice transmissions come over fine

How far are you from the digipeater? When I was trying to use a Baofeng with a Mobilink for APRS I had to be within 10 miles+/- of the digi to receive packets. At the time the closest digi was about 25 miles from me and I was using an external antenna. I went to a mobile radio instead (still using the Mobilinkd) and didn't have to fiddle with it to get it work.
You may have a couple other settings you need to change, I was advised of them after I had already ditched the Baofeng though I don't regret ditching it at all.
 
I can set up the D710G as a digi-peater in the truck and still not receive anything on the Baofeng 100' or less away. I'll set the squelch at zero and just monitor the frequency listening for anything coming over and it's just the noise floor, no signals of any kind. I'm on the Eastside of Seattle and there's a lot of APRS traffic all the time in the area. Two different HTs
 

Jim(tm)

New member
Picked one up recently too, Planning to use it with a Baofeng HT for APRS. So far having trouble getting it to work. Actually, I don't think it's the Mobilinkd with the problem. I think the problem is with the Baofeng(s) not receiving APRS transmissions. I have 2 different ones and neither seem to recive anything. Squelch is turned down all the way, have tried it at different levels and still nothing is coming through. I have checked this standing right next to my D710G in the truck which is receiving APRS transmissions the whole time. I understand the squelch on these cheap radios may not open fast enough, but they don't seem to pick up anything. Voice transmissions come over fine

Did you set the PTT style to multiplex and adjust the radio's output volume with the mobilinkd config app?
I've noticed mine won't receive anything with the whip antenna if it's indoors. When I connect it to my roll-up J-pole or take it outside, I start getting stuff.
 
Last edited:
Have adjusted and tried most if not all the settings on the mobilinkd config. Will play around more with it outside and see if the radio will pick up transmissions, had figured the mobile in the truck digi-peating would be strong enough to push it indoors from 50' but you never know...

That's half the fun of this stuff, figuring out the problems, then beating them into submission
 

snare

Adventurer
I just picked up one of these to set up my HTT to do APRS on my motorcycle:
https://store.mobilinkd.com/products/mobilinkd-tnc2-2
I'm still waiting for a password for APRSDroid but it looks pretty slick. It's tiny, has bluetooth and its battery is supposedly good for up to 48hrs of operation.

In case you havent received your passcode yet, and for anyone else who would like theirs...you can get it instantly here:

https://apps.magicbug.co.uk/passcode/

And for APRS I decided to go with a simple 2 meter radio (Radio Shack HTX 212 ), had a cable made that connects to a MobilinkD (and also powers the MobilinkD). THe MobilinkD bluetooths to my android tablet (or my phone) running APRSDroid. I have a Nagoya UT72 mag mount on the roof for the HTX212.

I turn this dedicated APRS mobile on through a dash switch controlled relay, and with MobilinkD's recently new capability to detect power on the USB charging port and auto power up, that one switch turns everything on except for my tablet.

This way I can keep BOTH sides of my dual band open.

Works perfectly for me.
 
I am thinking of doing something similar, but with an additional function. I want to be aware of vehicle location 24/7. Having a collectable vehicle that has virtually no security and can be stolen in seconds is troubling when leaving it parked somewhere. I have added additional security features but you will never stop a thief.

Not tying up one side of a dual band radio would be nice although I don't do much UHF or have a need to monitor 2 VHF. It is nice to have just in case.

Just took a look at Byonics to see if he had anything new and he does. He offers a 2m transceiver and modem with bluetooth built into a Pelican type dry case. It comes in 8 and 40 watt versions. Most of the time I could care less about sending messages mostly just location. Having bluetooth would give me the ability to send messages when needed. I could run APRSDroid when needed, otherwise it would run standalone.
Nice thing about the unit is I could hide it anywhere. You can bet anything on the vehicle is going to get tampered with. Just need a hidden half wave antenna.
https://www.byonics.com/mtt4b
 

Forum statistics

Threads
185,541
Messages
2,875,682
Members
224,922
Latest member
Randy Towles
Top