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UI Packet formats for Space



There has been discussion on the SAREX list about the best UNPROTO path
for use via the ISS digipeater.  If I may make the following suggestion
for all space based UI digipeating so that everyone can see your packets:

1) Make your UNPROTO like this: UNPROTO CQ VIA NOCALL,GG##GG,NAME
2) Begin each typed message packet with a ">"

Here is the background behind this recommendation:

1) The Kenwood all-in-one APRS radios and APRS in general only accept
packets transmitted to everyone on the net, not to individuals.  Thus
hundreds of people monitoring the downlink may not see your packets unless
they use the TOCALL of CQ, QST, BEACON, ID, APxxxx, etc.
Thus, CQ seems a good choice for this purpose.

2) The APRS format for a STATUS packet begins with a ">".  If your text
begins with ">" then it will be captured and displayed on the front panel
of the Kenwood radios and also captured as a STATUS message in all APRS
software.

BOTTOM LINE AS SEEN ON A KENWOOD TH-D7 HT OR MOBILE D700:

1) If you do not use "CQ" (or other group call) then your packets are
ignored completely by these radios and by APRS in general.

2) If you do use "CQ" but not ">", then they will see your CALL only:

+-------------+  Will flash for 10 seconds after each packet but
| WB4APR ??   |  nothing will be captured, since there was no ">"
|  ---------- |  format character telling the radio what to do with it.
|  ---------- |
+-------------+

3) If you do both CQ and ">" then...

+-------------+  Will flash for 10 seconds after the packet and the
| WB4APR      |  first 20 chars will be captured to the STATION list.
|  Using new  |  Being captured, the message can be redisplayed at
|  HT to demo |  any time by hitting the LIST key.
+-------------+

4) If you really want to get fancy and send up to a 45 character message
to a Kenwood HT or 64 characters to the Mobiles, the ARISS web page, or
all of APRSdom, then begin your message with either of these two formats:

   :BLN1keybd:Hi everyone, this is a bulletin to all HT's
   :W3XYZ    :THis is a pt-to-pt message to only W3XYZ's mobile.

Notice that the BULLETIN must begin with BLN# and both examples must have
exactly 9 characters between the beginning and ending
":"s.  These APRS Messages will be captured to the radio's MESSAGE list
and will BEEP the radio and TURN ON the BACKLIGHT and will flash the
mesasge 10 times.  THink of it as a text pager...

I hope these formats will help everyone enjoy the UI digipeaters in space
and will let everyone see everyone.

Notice, that nothing above has anything to do with position reports.  That
is another subject.  If you want your POSITION to show on all APRS
systems, Kenwood radios and ARISS web page, then you must begin each
packet with [GG##GG] gridsquare.

But this is inconvenient for all keyboard operators only using a TNC.
But if we could get everyone to agree to put their GG##GG as a DIGI field
AFTER the NOCALL, in the unproto field, then I am sure that all APRS
authors will be willing to consider looking there for a grid square and
accepting that as a position for display.

Then at least the ARISS and future PCsat WEB pages would capture your
grid..

There are 3 UI DIGIPEATERS in space now:   ISS, UO22 and OPAL
There are 3 others but require PSK modems: AO16, LO19, IO26
There are 2  more on the launch pad:       PCsat and SAPPHIRE
There are 2 more manifested for next  year

WB4APR


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