[aprssig] AVRS Online

Bob Bruninga bruninga at usna.edu
Sun Jan 16 10:31:41 EST 2011

> Please tell me you're kidding.  Is that not a violation of some spec
> somewhere?  Do you think callsigns should be case sensitive?  Are there
> arguments for/against having case sensitive callsigns in APRS-IS?

Here is my opinion, (not necessarily accepted by all)...

TNC callsigns are only originated as Uppercase in most TNC's.  And I think
it is good practice to always TX callsigns in uppercase.

Here is where it gets complicated.

Objects can be mixed case, and should RETAIN case sensitivity.  Rememebr, an
object (now that we have the APRS-IS) must be globally unique or it gets
confused with others of the same name.  I intentionally wanted mixed case
object names so that people could be creative in making their object unique
by the mixed case.  Some systems such as FINDU.COM treated object names
without case sensitivity, and so Lead and LEAD were treated as the same
object. (I have not checked FINDU to see if that is still the case).  But it
really confuses things.

However, LOWER CASE callsigns in MESSAGES can be sent within the APRS spec.
And I think that AX.25 can even allow lower case over the air, though no one
transmits it.  So in that case, I think that for the purposes of receiving
and ACKING messages, that CALLSIGNS should be case insensitive.

Does that help?

Bob, Wb4APR

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