Last month we had a presentation on conversational digital modes using Fldigi.
Thanks to Bob, N2LO, here’s a link to his study of the Narrow Bandwidth Emergency Messaging System — nets which use modern digital modes to send traffic, mostly on 80 Meters. The link below distills several postings by Bob and others on our list server:
http://n2re.org/notes-on-nbems-narrow-bandwidth-emergency-messaging-system