VOIP / Asterisk / Phone Interfacing

For nearly a decade I tinkered to my hearts content with various applications and packet radio. I learned an immense amount about TCP/IP. From DOS based NOS packages, which lead to ethernet networking the shack, later to Linux.

Well, I have been tinkering with Asterisk for about 6 years with the same enthusiasm. Much to my surprise, I learned that one of the original founders of our ham technology club has man of the same interests. So much love that Mike Kassner has the vanity callsign, K0PBX to reflect that.

When it comes to interacting with other people not in the hobby, messages (sometimes emergency) are relayed person (ham) to person, and the second most common way is by telephone.

As a mater of fact, telephone communication is probably the largest part of non-face to-face communication.

So like a good ham, being knowledgeable in how the telephone system works and is changing is always beneficial.

With some quick research you'll learn that SIP has become a widely adopted defacto protocol. You'll also learn that an open source Linux based application called Asterisk is a very powerful tool that many hams are playing with.

I was most pleased to notice that the second edition of Jonathan Taylor, K1RFD's VOIP book does elude to a whole new world using Asterisk and app_rpt.

In my opinion, the ham radio tie-ins are just starting.... What a perfect time to get jump on board and help develop something new.

http://nerdvittles.com/ - You'll find an immense amount of tinkering ideas here.

Southeastern Asterisk Radio Networks - Digital Amateur Projects Association (DARPA).

EmComm & AMSAT's Geostationary Satellite

A very interesting overview of AMSAT's phase IV Geostationary Satellite and the possible emergency communications implementations is in the Fall issue of CQ-VHF.

As you can tell I don't have a lot of love for Emcomm, but here is something that actually makes sense. A high speed multi-media capable, geostationary satellite.

AMSAT has recently begun negotiating with INTELSAT to get amateur radio communication payloads “piggybacked” on commercial geosynchronous communications satellites. This would be a first for amateur radio. It would allow earth stations to have 24/7/365 communications over a very large area using small fixed antennas. A small dish antenna would be able to access voice communications and text messaging. A larger dish antenna could provide access to video and high speed data. Because this has obvious value for emergency communications, AMSAT hopes to get considerable funding for this project from emergency communications agencies.

Hams are well acquainted with radio coverage problems while providing emergency communications. The high frequency bands suffer from hourly to daily propagation challenges. VHF and UHF simplex channels have limited geographic coverage. A repeater improves coverage while restricting all operations to its fixed channel pairs. Most of our current operating modes offer voice communications only. If data is transmitted it is supported at low rates such as 300, 1200, or 9600 baud.

I hope this gets some backing from the ARRL ARES directors. I honestly don't understand why and how all these recommendations come down the EC line to promote stuff like WinLink. They should all get behind something like this that makes sense, and help promote development and deployment of terrestrial HSMM networks.