Of Shooting Stars

Meteor-scatter (MS) propagation gets little attention in the American Amateur Radio press. A recent exception was the article by Clark Green, K1JX, in the January 1986 issue of QST. The European Societies have more frequent mention, usually of CW contacts at high speed. These references are to manually operated contacts using conventional modulation modes.

QEX, in August, 1984 announced MS tests planned using packet radio. The tests were timed to take advantage of the Perseids meteor shower. In October, 1984, QEX carried an article by Bob Carpenter, W30TC, of routine 1200-baud contacts between W30TC in Rockville, MD and W0RPK in Indianola, IA.

Jerry Stover, W5AE, wrote us to ask what's happened since. (Unfortunately, not a lot!) He believes it could well be the most reliable long-haul communications medium that amateurs could use. Before he retired, he was Chairman of Communications Industries, Inc, whose subsidiary, SECODE Electronics built the equipment used for the SNOTEL MS system with over 500 remote sites in ten western states. They ran all sorts of tests between Dallas and Washington, DC—a 1400-mile path and somewhat longer than the typical 1200-mile range usually cited. Jerry writes:

"The neat thing about MS is that it ties in with the packet-radio and computer age of ham radio so very closely. Also, due to the small footprint, QRM would not be a problem if all hams settled on just one or two channels in the 50-MHz band.

"I could envision that MS stations using autostart equipment could be spotted over the country to form a nationwide traffic net that would be there day and night, sunspots or not. With packet techniques they could store and forward automatically to the end station where it would then jump to local 2-m nets for delivery.

"Hams should be able to use 1 kW and 10 dB of antenna gain to handle some long-haul stuff to go VE-VO-OX-TF-GM for the transatlantic.

"The whole key to a nationwide system would be establishment of a standard format, protocol, frequency, etc, and the League is the proper group to do just that."

Well put! As packet radio now stands, up to 8 relays are possible with AX.25 protocol using 1200-baud 2-meter digi-peaters in many areas of the country. Most of these areas are connected by HF skywave between WQfRLI computer-based message systems that serve as HF-to-VHF gateways. These gateways could have been, and still can be, connected by means of 6-meter MS. A minimum of 12 MS gateways each connected to 2-meter packet-radio nets capable of up to 8 relays apiece could provide reliable store-and-forward service to the entire contiguous 48 states.

So what's stopping us (other than a piggy-bank account, and burnout)? First, there are lots of packet-radio terminal-node controllers (TNCs) around these days. But, 1200 bit/s is too slow for MS; 9600 would be a lot better, but 9600-bit/s mo-dems(compatible with the few existing 6-m radios) are not available. I believe that a 9600-bit/s modem capable of interfacing with something like the ICOM IC-551 and designed to have a bandwidth not to exceed 20 kHz at -26 dB points would be the catalyst to make MS packet a reality. W1AW has everything needed to get on MS with 1 kW except the modem. I'm sure that other stations would be willing to participate in experiments. If you would like to be part of the solution, please drop me a line. On-the-air tests would help us to optimize protocols for the MS environment.

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