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SUNSAT Downlink.



I just went out from work to watch the first evening's SUNSAT pass 
(a low 8 deg elevation pass) over the Atlantic on my Mobile
TM-D700 and can report the following:

1) I capture all  packets that light only 1 or more LCD segments
2) I captured several minutes of packets even on this low 8 degree
   pass (yes, my mobile had a clear horizon to the east)
3) I noticed that during the day, I had captured packets from earlier
   passes from KB2WQM in NJ, KC8MZM in Akron Ohio and N5SUB in Texas.

ALthough my WEB page describes operations in detail, I thought I would
boil it all down for anyone who simply wants to leave the rig on in their
mobile and see what they capture.  Here are the  minimum settings to
CAPTURE packets form SUNSAT on your TMD700 mobile.

1) Set TNC APRS mode
2) Tune to 145.825 RECEIVE on band A
3) Tune to 436.290 XMIT on band B  (and tune it during the pass)
4) Set APRS DATA BAND to RX:A and TX:B
5) Set APRS SPEED to 9600 baud
6) Set APRS PATH to SUNSAT
7) Set Packet rate to one minute or so
8) Set Transmit to AUTO
9) Add the wildcard * to your MESSAGE GROUPS

EXPECTATIONS:  You will hear data bursts once every 10 seconds
which are the TELEMETRY packets.  In addition, you will hear other bursts
if anyone digipeats or when SUNSAT sends a bulletin.  The BULLETINS and
messages from others will be captured and displayed.  To see the
TELEMETRY or other raw packets, press the PACKET MONITOR (P.MON) button.

Start your uplink on 436.280 at the beginning of the pass and end on
436.300 at the end.  But with typical trees and buildings, you probably
only need to concentrate on the central .285, .290 and .295 uplinks.

DO NOT:  DO NOT just leave your tranmit ON during the evening.  The
mid-USA pass is always a VOICE pass and we are NOT authorized to use
packet during voice passes.  Please.  But DO Go out and listen to it if
you havent heard it before.  Its Great fun.

So there you have it.  Mobile-to-Mobile live packet communications.  FOr
details:  http://web.usna.navy.mil/~bruninga/astars.html

Your OLD THD7 will also receive these packets in TNC-PACKET mode with a
laptop, but the NEW THD7(G) can operate 9600 baud in APRS mode and so it
will  capture all the above packets directly to the screen, just like the
mobile.  (And the old ones can be upgraded...)

Enjoy
de WB4APR, Bob

P.S.  It is OK to set the squelch. There is enough TXD to get the packets
anyway.  Besides the difference between OPEN Squelch and 9600 baud is so
slight you might not even notice them.  But with the squelch, they are
clearly there...

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