[aprssig] How to deal with DTMF keypad differences betweenmanufacturers

[Robert Bruninga]

> Another issue, was ... "long" callsign DTMF 
> strings, ... up to 18 DTMF digits... but various 
> [radios] have only 15 to 16 DTMF digits memories.

I'd like to compile a table of DTMF memory length and whether a
keypad alphabet is printed on the TT-pad.

Anyone that wants to add to the table send in your limits and I
will build the table..

THD7 has 16 and alphabet with 1=QZ
D700 has 16 and alphabet with 1=QZ
FT470 has ?? And alphabet with 7=PQRS

(though neither the D7 or D700 will ever be used on APRStt
probably...)...

Bob, WB4APR