Date: Sat, 20 Aug 94 04:30:02 PDT From: Advanced Amateur Radio Networking Group Errors-To: TCP-Group-Errors@UCSD.Edu Reply-To: TCP-Group@UCSD.Edu Precedence: Bulk Subject: TCP-Group Digest V94 #178 To: tcp-group-digest TCP-Group Digest Sat, 20 Aug 94 Volume 94 : Issue 178 Today's Topics: Nationwide RF Network X1J gurus? Send Replies or notes for publication to: . Subscription requests to . Problems you can't solve otherwise to brian@ucsd.edu. Archives of past issues of the TCP-Group Digest are available (by FTP only) from UCSD.Edu in directory "mailarchives". We trust that readers are intelligent enough to realize that all text herein consists of personal comments and does not represent the official policies or positions of any party. Your mileage may vary. So there. ---------------------------------------------------------------------- Date: Fri, 19 Aug 94 22:46:06 CST From: k5yfw@k5yfw.ampr.org (Walter D. DuBose - K5YFW) Subject: Nationwide RF Network To: forrerj@frl.orst.edu, gerry@cs.tamu.edu, kurt@cs.tamu.edu, John, Greg, RE: TPRS Quarterly Report, Vol 10 - Issue 4, May 1st, 1994, " Dayton NETSIG Meeting, A Summary". I take issue with item one "Can we build a nationwide RF network in the foreseeable future? The consensus was that we probably can't." Using the existing TCP/IP gateways (moving as many as possible to 9600 bps - 19.2Kbps (perhaps some to 56Kbps) and a high speed HF data network using TCP/IP, this *IS* possible. Perhaps not for FTP, TTY, TELENT or Convers use but surely for SMTP. How can we do it at G-TOR or perhaps CLOVER II speeds and there isn't even a AX.25 driver or gateway software, ie AMTOR to packet. The answer is simple. We, hams, must build a low cost alternative to the MIL-STD- 188-110c modem "protocol" or equal. This may mean using the TAPR DSP box or perhaps using a 16 bit, DSP/ASP soundcard (soundblaster) as an external modem to a TNC running in KISS mode. The MIL-STD specifies two types of modem "protocols" both capable of 2400 bps with a baud rate near 45 baud...please reference articles on CLOVER by HAL for the reason for a low baud rate. The most likely protocol candidate is the 39 parallel tone modem using QPSK (two mark and space signals on each tone. The transmitted bps rate is close to 3600 bps but with the Reed-Solomon coding used for the robust FEC, the transmitted thru-put rate is 2400 bps. Oh yes, the band width *WILL NOT* be 500 Hz...actually less than 3000 Hz but considering the thru-put, I believe our crowed hambands *CAN* handle the signal bnadwidth. Afterall, you already have 10 AX.25, 300 baud QSOs going on on 20 meters with a thru-put less than AMTOR. This modem technology is *NOT* pie-in-the-sky technology or vapor ware. If you have $7,500, you can purchase one of these modems from Fredericks Electronics or perhaps Harris RF Comm. in Rochester, if they have come down on their price. Don't bother calling Rockwell-Collins or Magnavox, they think there's are worth more than gold. Both Johan, KC7WW, (forrierj@frl.orst.edu) and Bob, N4HY, know that this is possible...and may have already succeeded in doing this. I know Johan is working in this direction and is presenting a paper on DSP to the ARRL Date Conf??? this weekend. Kurt, WB5BBW, indicated that he has talked to programmers at Texas A&M Univ and they feel this is possible using the "right" commercial-off-the-shelf DMA soundcard. My proposal and challange to TAPR/TPRS/ARRL and others is to develope this modem as an add-on to a TNC or used in the TAPR DSP box. AmprNet LANS would connect to gateways, some already having InterNet connectivity, and to the AmprNet WAN on HF. SMTP E-Mail, ham-to-ham messages and 3rd party traffic, would be over routed over the AmperNet WAN and SMTP E-Mail to the InterNet routes by InterNet connected gateways to InterNet accounts. I'm not a crazy old man, the DoD has been using the above referenced modem protocols for over six years. As Chief of Communications for the Air Force Aeromedical Evacuation System, I have seen the modems work in several demonstrations and they were used during Desert Shield/Storm. What DoD agencies (Air Force, Army and Navy) have not done is use them modems as an external modem for Ax.25 transmissions. The combination of the Forward Error Correction (FEC) and low baud rate of these modem "protocols" make an extremely robust communications media for HF use. Typically the bit-error-rate (BER) at 2400 bps using these modems, at the same S/N ratio, is equal to AMTOR but with 53 times faster data thru-put rate. Yes John, there is a Santa Claus...and we are the Santa Claus. All we have to do is give ourselves the present. Best Regards, Walt/K5YFW ------------------------------ Date: Sat, 20 Aug 1994 00:38:02 -0230 (NDT) From: Wilson Penney Subject: X1J gurus? To: "Michael H. Foster" On Wed, 17 Aug 1994, Michael H. Foster wrote: > Has anyone optimized their x1j parms? > With several band openings over the past few weeks, the x1j's locally > lose their buffer space and hose up until a reset is given. We are > trying different parm settings hoping the node will release it's buffer > space faster, but we have no serious documentation to guide these settings. > Can anyone provide any insight or specifics? > > Thanks in advance, > Mike, wa5txx > mfoster@amoco.com > You may try joining the NEDA (north East Digital Association) NEDA publishes the NEDA Quarterly and a NEDA Annual. I have been a member for 2-3 years and find it is the only publication that I know of that is devoted to packet. It covers TN2.08 ,TN2.10 and X1J listing all suggested Parms and mode settings for USER PORTS #DPPL #HTSF MULTIWAY and GATEWAY. We here in Newfoundland are running X1j at USER sites and we are now putting 9600 backbone links across the island (a distance of app 1000 km) Membership dues are as follows: Associate/Subscription with U.S. addresss.............$15.00 Voting with U.S. address..............................$25.00 Associate/Subscription with Canadian address..........$20.00 Voting with Canadian address..........................$30.00 All membership rates are U.S. funds only. ADDRESS IS: NEDA P O BOX 563 MANCHESTER NH 03105 This publication to me (I burn all the EPROMS for NFLD) was a gem, We would be likeworking in a OUTHOUSE with out a flash light...HI. If you subscribe ask for the NEDA 1994 ANNUAL , IT is 174 pages in total and has all the latest info.. P.S. I am only a member andonly trying to be of some help. 73 VO1BK ------------------------------ End of TCP-Group Digest V94 #178 ******************************