Thursday, January 27, 2011

New D-Star Developments



Above is a D-Star Support Matrix document that Scott, NS7C compiled. It's a good overview of what works with what.

"With all the various hardware and software options available, I sometimes forget which hardware works with which software."



Just before Christmas I asked on the dstar_digital group about decoding D-Star DTMF. I have found that is way to clumsy to have to handle all control functions using the URCALL fields. (especially when mobile)

About a year ago I had played with trying to decode it. I saw patterns, but wasn't able to define them, and had read that it might not ever be possible to use DTMF on D-Star as some thought it was implemented incorrectly by Icom.

Just after Christmas, Michael, DL1BFF proved this wrong. Turns out after cooking up some code to handle the bit interleaving and FEC processing, the DTMF is there just like the manual says.

To compliment this, Kristoff, ON1ARF has been working on some voice-announcement software.

This includes a wav2ambe tool, that uses a DV-dongle to encode multiple files in sequence to produce one single .dvtool or .ambe file. (useful to generate an announcement "on the fly" based on a sequence of wav-files).

As well as a wavstream tool to stream multiple wav-files in sequence. And ambe2wav - a new tool that can decode one or more AMBE-encoded audio-file (.dvtool or .ambe format) back into a wav-file.

He is also working on generating a predefined AMBE word / letter pack. This will enable D-Star repeaters to be able to concatenate words for announcements without the need for a DV-Dongle attached.

With these two tools, you will be able to setup scripts to speak weather reports and the like, just as hams have done with IRLP.

Also think of custom greetings and queries.

"Welcome Steve to the N9DKH D-Star repeater, the temperate is 67 degrees.".. when you make your first transmission after being idle.

You should also be able to query over the air when your friend was last heard, as well as just about anything else you can think of.

Scott, KI4LKF is still at it. His latest was working in D-Star voice mail.

YRCALL=_ _ _ _ _ _ S0
The above command will Store/create voice mail in the dvtool file x_voicemail.dat
YRCALL=_ _ _ _ _ _ R0
The above command will Recall/playback voice mail from the dvtool file x_voicemail.dat
YRCALL=_ _ _ _ _ _ C0
The above command will Clear/delete voice mail. File x_voicemail.dat will be deleted.
In all cases, the letter x in the file name x_voicemail is the module A,B or C


All very interesting ham developments worth checking out.

Intellectual Property

If you know me or have been reading my blog long enough, you know that I am a proponent of open source concepts.

I remember posting to the Texas A&M Mailing list back in 2007 because I was running into a glut of roadblocks related to Intellectual Property in various projects that I was dabbling with at the time.

"Leaders in the ham radio arena who are to busy beating their own chests touting things like they are the "national association for amateur radio."

These so called leaders need to suggest/ lay some general concepts to steer the hobby to the future.... focus on spreading the importance of the open source concepts in the ham radio arena"


In my last big project the 73 Magazine Index, I realized that its contents will become lost to posterity due to intellectual property issues. A dirty shame....

Interestingly enough, I have noticed that TAPR has grasped the open concept.

They came up with an Open Hardware License, and I just noticed that the DCC DVD I bought was licensed as a Creative Commons 3.0 Share-A-Like work.

Consider this:
TAPR's membership journal publication, the Packet Status Register (PSR) featuring both technical and non-technical articles is an authoritative source for up-to-date user and technical information on digital issues.

Explicit permission is granted to reproduce any materials appearing herein for non-commercial amateur publications provided credit is given to both the author and TAPR...


Yet I just noticed on the front page of the ARRL's site:
Copyright © 2010 American Radio Relay League. Reproduction of material from any ARRL Web page without written permission is strictly prohibited.
Also: http://www.arrl.org/copyright-faqs

I've also noticed that "ARES" is registered trademark of the ARRL and so forth.

I'm sorry if I have not properly denoted all these various trademarks. It's not intentional, it's just an encumberment that I don't have time to keep up with.

The reason I decided to blog about "Intellectual Property" is because my local ham club is in a potential law suit over IP use that could effectively flush this non-profit educational organization of all it's assets.

So I encourage you to think about all this, and how productive or non-productive intellectual property is to the hobby and the world.

Here are some of my favorites:

Revolution OS

The Code Linux

Pirates of Silicon Valley (you can't watch this online due to IP, but it's worth watching)

http://www.fsf.org/

http://www.gnu.org/licenses/gpl.html

Sunday, January 2, 2011

Understanding Digital

Okay so maybe the last couple microwave projects that I posted were not your bag.

There have been a few good videos from Hak5 lately.

If you aren't familiar, Hak5 is a weekly "home-grown" video podcast about computers, and technology.

I highly recommend it, and since someone left blog comments about the concept of more video content, well here you go.

If you are an old-timer, and videos on the web are too hip for you, I expect you to read Make Magazine.

A couple weeks ago the Hak5 crew covered Pulse Code Modulation. And the following week, Time Division Multiplexing (TDMA).

Both concepts in the show are used in relation to the telephone network. But they are both critical concepts to the basis of digital communications. (i.e. non-cw and other archaic forms of communication.)

As an example of how this ties in, I've been playing with Mototrbo, which happens to be a two-time-slot digital TDMA two way radio technology.

Remember: I'm trying to help hams expand their understanding and explore new ideas with my blog.

I can't be successful unless You spend time less time drooling (like full-fledged ARES member with down-syndrome) and ogling that utterly useless QST magazine.

Read something that will help your brain, and the hobby! I'll send you issues of 73 if I have to!

Saturday, January 1, 2011

Mad Scientist

I was happy to see DIY (Do it Yourself) on the cover of the January QST again.

I found the directional coupler - power/SWR meter article interesting, yet disappointing as it is only for HF.

The OP-ED member view point from Eric, KL7AJ titled "Put the Mad Scientist Back Into Ham Radio" reflects my own view point very much.

Eric points out the difference between his generation of Amateur Radio experimenters and today's batch of obsessed appliance operators.

"In our day, it was our job to create emergencies. The new EmComm oriented hams are intent on fixing emergencies."

He's referring to setting accidental fires building Tesla Coils, or Jacob's ladders, and things of this nature.

He makes a good point. If we want young blood in the hobby, we have to compete with paintball, bungee jumping and extreme skateboarding.

I highly recommend giving his opinions a read on page 82.

If you are ready, here is a nice experimental project from my Mad Scientist friend.

You know you are ready for the accidental RF burn from this 100 watt 2 GHz amplifier.