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SUNSAT APRS SAT-GATES!



Tie these two messages together and what do you get?

> > Bob's mission, to find ways to use the satellites for the lonely
> > traveler" ... does not work, and cannot work without volunteers
> > systematically listening to the downlink....

And:       > ... the SUNSAT mode-B APRS test will continue! 

And: the fact that there are over 70 full time IGates that only need to
plug in their D700 or THD7 or other 9600 baud TNC on 145.825 and we will
have a worldwide Satellite APRS system in place OVER NIGHT!

Since the SUNSAT DIGI downlinks NOTHING but APRS, and then only
periodically at a very low duty cycle, all ANY IGATE operator has to do is
DIODE OR the output of his D7 or D700 monitoring 145.825 SUNSAT with the
output of his TNC monitoring 144.39 and ITS DONE!

   From D7 or D700 on 145.825  >-------->|-------+
                                          d1     |         Pin-2
   From 144.39 radio on 144.39 >--+----->|-------*-------> Into IGATE
                                  |       d2     |         serial port
                                  +---/\/\/\/\---+
                                        10k
At 9600 baud and with only about one packet every 6 seconds or so from
SUNSAT in view and one very 3 seconds from 144.39 the probabiliy of a data
collision is a tiny fraction of a percent and not worth worrying about...

Maybe some of the APRS<==>IGate software already accepts multiple TNCs on
multiple ports..   Then all you gotta do is plug it in!

de WB4APR, Bob


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