[aprssig] OT: Yaesu to release digital amateur radio gear

[Heikki Hannikainen]

On Mon, 9 Jan 2012, Stephen H. Smith wrote:

> On 1/9/2012 6:12 PM, Amateur Radio WB8NUT wrote:
>> DMR was developed for the public service market, such as police, fire, etc.
>
> Actually it was developed by ETSI (European Technical Standards Institute) as 
> a multipurpose digital radio protocol for public safety, utilities, 
> commercial land mobile AND for inexpensive consumer devices similar to our 
> FRS (Family Radio Service).

There are a couple of new vendors, Simoco and Tait, starting to produce 
DMR gear, which will be compatible with Motorola's MotoTRBO and what 
Yaesu announced:

http://dy.fi/dqq
Simoco DMR technology previewed ahead of February 2012 launch

http://transport.taitradio.com/transport-solutions/dmr/overview
Tait DMR Solutions for Public Transport Operators

Hytera sells DMR radios and repeaters already.

>> D-Star was developed specifically meet the needs of amateur radio.

Routing by callsign is a plus for D-Star. DMR uses numeric IDs to identify 
radios, and requires amateurs to maintain a central database of 
callsign-to-ID mappings (http://www.n6dva.org/trbo-database/index.php).

If I've understood it right, the current amateur DMR infrastructure only 
consists of a large linked repeater network, which apparently works like a 
single big repeater. Someone talks, and it's transmitted all over the 
whole network.

It should be possible to create a network which would allow point-to-point 
calls (on-demand linking of two repeaters), using the ID numbers. But that 
doesn't exist for DMR. D-Star has it.

On the other hand, I can send and receive APRS messages using the DMR 
radio I have, using the APRS-IS gateway program published on the MOTOTRBO 
yahoo group. D-Star doesn't have that. (I guess that phrase puts this in 
context for this mailing list. :)

> One huge advantage of DMR is that you can achieve 4800 BPS data transfer in a 
> 12.5 KHz channel or 9600 BPS in a classic 25 KHz channel (two 12.5KHz DMR 
> channels bonded) for non-voice uses, even on VHF or UHF.

Unfortunately it doesn't seem to be a clean IP or even clean UDP pipe. 
Only a few specially configured UDP ports are passed from computer to 
computer. So, to do email or file transfer, you'll need a special 
application or application-level proxy to get that through the radios (a 
bit like D-Rats). The 1.2 GHz D-Star radios apparently provide an Ethernet 
bridge so just about anything that works on the Internet will "just work" 
(although a bit slow).

I have both an ID-1 for 1.2 GHz D-Star, and TRBO rigs. Must try data 
transfers on them soon (haven't had the time to do it yet - beta.aprs.fi 
and some other things are higher up on the TODO list :).

   - Hessu