Survival UK Forums

In the US most long haul disaster radio communications between state EOCs, FEMA, military and NGOs use digital modes.

A list of nets can be found here: http://hflink.com/nets/

A description of automatic link establishment (ALE) can be found here:
http://en.wikipedia.org/wiki/Automatic_l...ablishment

A comparison of common amateur radio digital modes can be found here:
http://www.pactor.com/compare.shtml

The mode used by FEMA and the military is MT63, which is also used by amateurs who are enrolled in the Military Affiliate Radio Service (MARS)
http://www.navymars.org/central/reg4/al/MT63.htm

A tutorial for using MT63 is here: http://www.navymars.org/national/trainin...ning_3.pdf

Digital Comms to most hams is running your transceiver through a digital interface into your computer using a program like PSK31. The net effect is a "chat" function that doesn't rely on the internet. Like most things there is "good news and bad news".

First, the "good news". You can broadcast at low power in a very narrow frequency range and send data quickly. Add a directional beam antenna to the mix and you'll be hard to find if you use this method judiciously.

Now the "bad news". You need a computer interface like a Signalink USB, and a computer, both requiring power, in addition to your transceiver. Next, you have to be using the same data program (PSK 31, fldigi, etc.) that the people you wish to contact are using.

Is digital the answer to all comms problems? No! Is it a useful tool to have and be familiar with? Yes, as is CW.