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PCsat Operating notes

Two suggestions for messaging via PCSAT, ISS, and other Space DIGIS:

1) Usually send MSGS to ALL, so that all can see them
2) If you send a one-on-one message, leave off the SSID. (prevents ACKS)
3) If you hear a digipeated packet right after you transmit even if you
personally do not decode it, it was probably you.  So no need to keep
forcing packets until you get a decode.  Most people will hear it.

RATIONALE:  Since 70% of the users on PCsat are using a D7 or D700 HT:

1) The Kenwoods will not capture or display messages to other people, so
"ALL" lets them read the mail if you just send messages to ALL, and then
indicate WHO in the body of the message if it is not obvioius.  THis
also makes it easier to send because you dont have to keep reloading
the TOCALL each time.

2) ACKS via these satellites are not good.  THey are rarely successful
and only add congestion to everyone else.  If you do not use the other
stations SSID, then he will still capture the message, but his radio
will not ACK it.  THus keeping ACK POLUTION down...  The D7 and D700 will
send one packet a minute automatically for only 5  times, so it cleans
messages out of the system quickly.

3) PCsat transmits with only 2 Watts. But it hears as good as you do.
THus PCsat will hear your D7 UPLINK  4 dB better than you hear it and
PCsat will hear your MOBILE D700 13dB better than you hear it!  So when
you hear it digipeat your packet, even if  you do not decode it, then you
were successful and can hold off a bit..

PCsat was designed for HT's and mobiles.  But I have to spend each of my
passes commanding and my Mobile now has a armstrong BEAM on it, so I
ccannot be gathering statistical data on how well PCsat is closing the
link to mobile users.  SO I hope that some of you are taking good notes
and substantial data so that in the end, we can say for certain if 2 Watts
on PCsat is good enough or if more is needed.

Agian, a 19" 2m 1/4 wave whip will do better than a 5/8 wave, so we need
lots of data to see if it is worth really drilling another hole for the
19" whip in your car for future satelites.

de WB4APR@amsat.org, Bob

PCsat WEB  page     http://www.ew.usna.edu/~bruninga/pcsat.html
ISS-APRS FAQ:       http://www.ew.usna.edu/~bruninga/iss-faq.html
CUBESAT Designs     http://www.ew.usna.edu/~bruninga/cubesat.html
APRS LIVE pages     http://www.ew.usna.edu/~bruninga/aprs.html
APRS SATELLITES     http://www.ew.usna.edu/~bruninga/astars.html
MIM/Mic-E/Mic-Lite  http://www.toad.net/~wclement/bruninga/mic-lite.html

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