[aprssig] APRStt gateway SITREP

Robert Bruninga bruninga at usna.edu
Thu Oct 2 12:50:34 EDT 2008

I agree with all, except I was feeling comfortable with the plan
of using
Multi-press, But the example of FF3ZZZ callsign and 23 digits
shows how bad it can be.  Maybe we have a "option" for some bad
callsigns...  But keep muilti-press for the rest...

Yes, the two-key method is best for CALLSIGNS.  But multi-key is
best for text messaging because you keep your finger and your
eye on the same key until finished.  Pressing 777 for "R" Keeps
your eye, finger, and mind on the "R" key until finished...
Ready for the next letter.   But pressing 73 for "R" leaves
your eye, finger and mind on the "3" key (which has "DEF" on it)
and for someone as scatter brained as I am, I will forget what
letter I just did, and which one I am doing next.  So the
two-key method is much worse for hand-eye coordination...

But then you are writing the code, and "he who codes rules"...

Leaving for airport.  Bye.


> -----Original Message-----
> From: aprssig-bounces at lists.tapr.org 
> [mailto:aprssig-bounces at lists.tapr.org] On Behalf Of F5SMZ 
> Jean-Philippe
> Sent: Thursday, October 02, 2008 12:24 PM
> To: aprssig at lists.tapr.org
> Subject: [aprssig] APRStt gateway SITREP
> Hi all APRStt fans, (and addicted keypad users)
> here is the situation today:
> 1) extensive testing, development and debugging is ongoing 
> here with the team (F4ASB: developer; F4ARO: "chief" beta 
> tester and debug and other local contributors from our 
> clubstation F8KHP in JN38EE)
> 2) concerning the DTMF keypad layout we made a choice today 
> in order to go forward and speed up things, by keeping in 
> mind that the callsign sequences (A) MUST:
> * be stored in a DTMF memory
> * will not exceed in ANY cases 16 characters (so the only way 
> to guaranty this is using the deterministic 2 digits manner 
> "à la " Echolink).
> * the ITU 161 DTMF keyboard layout will be used (as GSM 
> mobile phones and Yaesu VX-8R)
> * will be usable in ANY country
> 3) ABREVIATED CALLSIGNS (suffix) must be as short as possible 
> to be reused for POS, MSG and QRY sequences.(3 digits max)
> 4) the APRStt gateway IS a "self-learning" piece of software 
> ... will explain below
> 5) Initial release is only IMPLEMENTING "A" sequences: 
> callsigns check-in/out.
> From a software development point of view I need to deliver 
> something as an UI-view add-on (initially) that works in 
> EVERY country whatever callsign prefix characters and length 
> rules are. This is ONLY for "A" sequences (callsign 
> sequences). In this way, ANY callsign with 6 characters will 
> be DTMF encoded with a maximum of 12 digits. We still need to 
> agree if "A" become "C" or not.
> As Bob mentionned yesterday, ABREVIATED callsigns will focus 
> on SUFFIX only; this way, we are able to build these 
> shortcuts with only 3 digits following a given algorithm. Ex: 
> my callsign F5SMZ (suffix SMZ) is computed by the gateway 
> "478" and sent back in vocal synth the first time I check-in; 
> I can reuse it in ANY DTMF sequence later (even for further 
> check-in/out) once I've sent the initial FULL sequence 
> corresponding to my callsign. The gateway store it in the 
> database and will always recognize my DTMF sequences in the
> This way, the APRStt gateway is self-learning; e.g as more 
> and more APRStt stations check in, the gateway update his 
> internal database AND compute the related ABREVIATED callsign 
> . The 3 digits ABBREVIATED callsign algorithm maintain a very 
> low probability to generate dupes; remember, APRStt is a 
> LOCAL application. Following this procedure we can add ANY 
> callsign (especially here in Europe where countries are 
> "small", and I can meet lots of stations from DL, LX and HB9 
> every day on a repeater as well.
> Hope we go in the right way; in case not, feel free to give 
> your feedback, proposals and ideas.
> 73 de F5SMZ, Jean-philippe
> f5smz at wanadoo.fr
> Skype: f5smz88

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