[aprssig] Text Messaging Radios now

Robert Bruninga bruninga at usna.edu
Mon Feb 9 08:52:59 CST 2009

>> I just realized that we can be using 
>> these dozens of thousands of text messaging 
>> radios now even without waiting for someone 
>> to write APRStt (DTMF). (www.aprs.org/aprstt.html)
>> These are the FT51 and TH78 radios...
>> www.aprs.org/FT51-TH78.html
>> Almost every ham radio that exists can send 
>> text messages from their DTMF memories!...
>> [TO these radios...]
> What, even radio's that don't have DTMF, APRS, 
> or any other digital stuff!  Cool...

Yes, they need a DTMF keypad, but there are very few if any HT's
sold in the last 30 years that don't have these for use on
autopatches and other remote control applications.

> Take care, there is an *Awful lot* of stuff 
> about that pre-dates the digital evolution...
> not everyone goes out and buys the latest...
> Even if you have such a DTMF/messaging radio, 
> is the messaging format for all the different 
> makes of radio, compatible with each other?

The format is #NNN#MMMMMMMMMMMM# where NNN is the group number
callsign, and MMMMMMMMMMM is the numbers reppresenting the
alphabetic letters.

Anyone with an DTMF keypad can send a text message.  But only
the FT51 and TH78 series radios can display them.  But that is
why all the excitement.  In many special event and publis
support activities, most of the data transmmission from the
field is from the users with the HT's back to Headquarters for
display.  So in the entire event, only one person has to have
the special radio that can display the data.  But any HT with a
keypad can enter and send it.

Please see www.aprs.org/aprsevent.html

Bob, Wb4APR

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