The next APRS satellite will have a DTMF uplink for people to get into the global APRS system with any old HT, not just the expensive APRS integrated radios. THey will hear a voice QSL in return.

I want to indicate all grid squares as 4 decimal digits for this application to keep it short. Instead of FN19 for my grid, it can be nn19 where nn translates on the spacecraft to "FN". I just counted and all of the countries and locations that have any nominal ham radio population appear to fit in under 60 major grids. We just need a mapping on the satellite to map these 60 in to the two digit nn number.

It would be nice if there was an easy encoding method so that an entire 60 deep table is not needed, but simply an algorithm. If any such system exists let me know.

As it is, I see exactlyl TEN major country areas, and so the first digit could simply indicate the area. And each of those areas have 0 or less smaller populous grids. So it should work out well.

Of course no one is excluded. Its just the 99.99% of hams that live in these 60 grid squares can encode their grid in 4 digits. Those anywhere else in the world will take 6 DTMF digits for their posi (2 each to spell the two letters)..

For info about APRStt (Touchtone) see http://aprs.org/aprstt.html

So, do I have to create and figure out a cute encoding method for this top 60 (to 99) list, or does something like this already exist?

Bob, Wb4APR