Bulletins from the Pacific Packet Radio Society - page 116

Frames to be repeated by a local area network simplex packet repeater also contain a third address field following the FMCALL field. This third field is the callsign of the repeater. More details on this protocol will be published in the revised AX.25 document.

Collectively, the group considered nearly every design which starts out with a statement something like this: "Holy 807's, look at all the overhead bytes you have in using call sign addressing. I can do it with just 4 bits." We have found that these other schemes have their own defects and that the penalty for the call sign overhead is relatively small in comparison to other delays on the link and in view of the other benefits.

The AMICON session ended with promises from various members to try to implement the required versions of this new protocol. In the interim, LIPM.04/TIPm.o4 will be used by AMICON groundstations until the new software is ready.

PACSAT
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Tom Clark described a potential opportunity in the late '84 timeframe for a new low-altitude orbital launch. Tom reviewed various considerations which led to the concept of building a satellite which would be an all digital store-and-forward transponder - a flying mailbox. This satellite would have a computer, two or more digital serial I/O channels, appropriate modems, and 1/2 to 1 megabytes of on-board memory. Messages put in on one side of the earth could be extracted on the other side. The operation would be somewhat like using a CBBS, but only for 15 minutes at a time!

Tom proposed a preliminary design, and there was an extended discussion of the pro's and con's of the project. Various implementation ideas were suggested. Den Connors and Lyle Johnson agreed to put together a more detailed PACSAT proposal for Saturday, and presented it at a seminar on the 9th.

The project concept was presented at the AMSAT general meeting, and since no opposition was raised , further development of the PACSAT proposal is expected.

FILE QST.82.10.15.0.KD2S

Tucson Amateur Packet Radio Activities
by Den Connors KD2S and Lyle Johnson WA7GXD

TAPR is back from a very hot summer, and we're readying for an onslaught of activity in an expanded number of Beta sites. As background, the summer found us switching the processor on our Terminal Node Controller board from a 6502 to the more powerful 6809, to allow for software protocol implementations using concurrent or multi-tasking systems. There are now three different groups working on software, with Lyle WA7GXD building up system primitives in assembler, and constructing a fully compatible VADCG LIPM04-type protocol. This first effort for hardware testing allows us to use Lyle's Vancouver boards in

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