[aprssig] DTMF encoding

[jimlux]

Bear in mind when talking about multiple key presses that most devices 
that use this have some sort of visual feedback (e.g. an alphanumeric 
display).  I'd hate to have anything like this with no feedback.  Hence 
directory lookup interactive voice response systems that ask you to 
enter the name using a single digit for each letter (using the 2=ABC 
scheme).. Hopefully that "hashes" to a unique identifier that allows the 
lookup to work. If not, they disambiguate by asking you "do you mean A 
(press 1) or B (press 2)"


Jim, W6RMK