GROUP.TXT         GROUP OPERATIONS WITH APRS
Document version: 8.6.9
Author(s):        Bob Bruninga, WB4APR 
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The GROUPS function in APRSdos was orignally designed for APRS users
who are also participants in the Navy/MarineCorps MARS system.  But this
techinque is so powerful, it has been extended to any GROUP system
and is now built into every copy of APRSmax.

Using the GROUPS function in APRSdos allows those members to all
selectively see each other and their GROUP (MARS) calls while keeping
on-the-air anonymity as a group and without any on-air association of
the cross service callsigns.

This anonymity is maintained by using a special cross-callsign file
at each participating group station.  This file named FOUO-GRP.DAT
is maintained as a For-Official-Use-Only file by that organization
and is closely held by members only.  APRSdos uses that file when
each new station is heard to check for a cross-referenced group call.
If found, the association is made and both calls afer displayed on
the APRSdos DIGIPATH page (hit D) and MAPS.

The Group calls show in bright RED on the map displays.  Also the command
JUST-GROUP will show only the group members on the Positions "P" list
and on the MAPS.  On the "D" page the JUST command can be used to further
sub-select any other string matches, such as separating ARMY, AF, or
Navy MARS calls, etc.  IE: JUST NNN will display only the Navy MARS calls.


OPERATIONS:  Other than locally displaying the group calls, the on-air
operation of APRSdos is unchanged.  Amateur Radio callsigns are
used normally, and the GROUP calls are not used at all, other than for
local display.  Note, there is no intent here whatsoever to use APRS
for passing any non-amateur traffic.  THe intent here is to simply keep
track of those APRS members who are on the air but who may be of
special interest to a group.

DETAIL SUMMARY:

Group Data:   The GROUP calls are listed in APRS\SYSTEM\FOUO-GRP.DAT
              If the file exists, it will always be checked.

Processing:   The associated call, once found, is placed on the "D"
              page.  This is a new "D" list format, so changes
              throughout old code were extensive.

New Commands: JUST-GROUP on the "P" list to see only the group members
              JUST-GROUP on the MAP to see only the Group Members

Processing:   The callsign association is only made the first time a new
              amateur call is "added" to APRSdos.  SO loading an old
              file with calls that do not have this association, means
              they will never get it either.  Best to do a FILE-NEW
              start the first time APRSx69 is first run.
              

