[aprssig] Use call without SSID?

[Curt, WE7U]

On Sat, 26 Sep 2009, Mr Jeffrey L Ross wrote:

> hi all, about this ssid, I am almost running out of ssid,s to use as i have 
> many stations and each need one. Not on APRS but regular packet. heres my 
> list: KC8GKF at this time:FBBBBS-APRS OBJECT

> What I just figd out the other day is that I can place a 0 in front of 1 or 2 
> or 3 etc all the way to 09.
> and they will be another ssid.
> I am wondering if the tnc,s will pick up on this and run with it. hmm
>
> or even use kc8gkf-00 as one.
> just wondering, add your coments if you wish, 73

Great idea, 'cept it won't work.  If you look at the structure of an
AX.25 packet frame header there are 4 bits allocated for the SSID
for each callsign in the path (SRC/DEST/DIGI's).  4 bits gets you 0
through 15, of which '0' is not normally shown but still present
(For instance WE7U-0 == WE7U).

If all of those stations are on the same frequency, you'll need to
either shorten your callsign via an upgraded license so you have
more chars to put numbers into at the end, or you'll have to run
some with tactical callsigns with your real callsign in a status
packet or in the comment field of your regular packets.  That last
works for APRS anyway.

-- 
Curt, WE7U.                         <http://www.eskimo.com/~archer>
    APRS:  Where it's at!                    <http://www.xastir.org>
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Windows:  Microsoft's tax on computer illiterates. - WE7U.
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