[aprssig] APRS Spec 1.2 Update (Mic-E PHG)

[Bob Bruninga]

An issue with PHG data in Mic-E packets was clarified in the APRS1.2
addendum:

http://aprs.org/aprs12.html

It was always the intent that the TEXT field of a Mic-E position packet
could also contain any valid field in the standard APRS position COMMENT
field.  Such as PHG data.

This issue came up, because now we have many Mic-E radios that can Digipeat,
and they should be able to include their PHG data too in their packet.  The
PHG data would begin where the text field begins...  and this means AFTER
the optional Mic-E altitude field.

The converse is not true.  You should *not* expect to see Mic-E altitude in
a standard APRS comment field.

Bob, WB4APR