Order Tray | Contact Us | Home | SIG Lists

[aprssig] IGate wildcards/Telpac data

Robert Bruninga bruninga at usna.edu
Tue Feb 15 16:29:04 UTC 2005

No, NO, NO.

The callsign field in APRS is and always has been 9
bytes.  Also there always was a minimum requirement 
of at least 3 bytes.  (im not sure if the 3 byte minimum
got into the spec or not).

Thus WL-CCCCCC is a violation since it makes for a
two byte call and a 6 byte SSID.  But CCCCCC-WL
is just fine.  Such a callsign cannot be "originated"
by a raw TNC, but that is a limitation of the TNC,
not a limitation of the APRS SPEC.  THus a received
callsign field of 9 bytes is OK as an object, or as a
3rd party format, or an item, or any of the many other
APRS formats with that 9 byte field.

But I do agree with Steve on FINDU or other applications
of gaiting to RF where the ability to wildcard a callsign
exists, that maybe that something is only considered an
SSID if it is 2 bytes long and at the end.  That is why
I like the CCCCCC-WL option...

de WB4APR, Bob

>>> steve at dimse.com 2/15/05 9:29:17 AM >>>
On 2/15/05 at 8:06 AM James Jefferson Jarvis <jj at aprsworld.net> sent:

>Are you talking about allowing callsign-ssid to be an arbitrary
>If so, then I object based on the fact that aprsworld and anything
that uses 
>it is expecting callsign-ssid to be at most 9 characters. IIRC the
>internet stream was supposed to look like AEA or TNC2 packets. Both of
>would only present at most 9 characters for callsign-SSID, so that's
what I 
>went with 5 years ago.
This specific issue could be addressed by not using any other SSID, so
even 6
letter calls fit in 9 chars (findU uses 10 chars). E.G. WL-WZ9ZZZ, and
using the
true SSID only in the object.

Still, the precedent will be set, and there is no reason to limit
callsigns to 9
characters, so I'm sure someone will want to use more in the future...

Steve K4HG

aprssig mailing list
aprssig at lists.tapr.org 

More information about the aprssig mailing list