Hi Andy, A system that implemented the ALE Data Block Message (DBM) ARQ protocol using the PC Sound Device Modem (PCSDM) which at a raw 125 baud with its deep interleaving providing a full 3x throughput on a good circuit where no ACK/NAK failures occurred would be much better. GTOR which blows away PACTOR I is blown away by ALE DBM and best of all it can be easily implemented on the PCSDM as the ACK/NAK is variable in seconds and not milliseconds. In MARS we sending messages using DBM ARQ and FTP on channels where GTOR and PACTOR I are failing, its really something to see for yourself. The DBM protocol is extremely robust and it supports bidirectional messaging as well which is an interesting twist when two stations are attended.
/s/ Steve, N2CKH At 07:20 PM 1/16/2007, you wrote: >Jose's comments have been helpful. I used VHF packet in the old >days and also used the first satellite gateway on the east coast. >run by my neighbour down the street! > >When I started this thread I had one goal in mind, a simple way that >hams can send brief email without use of the Internet , without >the use of expensive proprietary protected modes (e.g. PACTOR II >and III), AND without a TNC (just using soundcard packet). > > Although 300 Baud is not very robust and quite slow, what would be > wrong with ...say, 10 HF Packet BBS's strategically located around > the world, perhaps on 30 meters? I would not expect them to > forward mail to local VHF gateways or use the Internet , instead > people interested in mail would connect to the HF Packet BBS > directly and retrieve their own mail. If all 10 BBS need to have > the same mail they could forward to each other via a backbone , > that would be a smaller task because the traffic load would require > less forwarding than if VHF or Internet forwarding was part of the plan. > >Of course PSK Mail might be a better plan but would need a Windows >release to make it more accessible to the Masses. > > From an "emergency communications" point of view, my goal would be > a simple method of communication that allows message storage. No > expected links to government communication networks, no elaborate > node interfacing to the Internet. Simply turn on a radio, activate > a computer, issue a "connect" command, enter a "Send Private" or > Send Bulletin" Command , type a brief message and save. > >Andy K3UK.
