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PCsat test results



Today I got to sit and watch my first two PCsat passes from my
mobile D700 in the clear.  Here are my observations between 1749z
to 1759z on a 14 degree elevation pass over New England and then
out over the Atlantic and then 1933z-1947z a direct overhead pass
from central Canada down over the East Coast.
                        PASS1 PASS2
                        ----- -----
Peak elevation:           14   85
Total packets heard:      50   40

Total decoded:             4    7  (TLM, Mine and KB2M-3, WA4EWV-8)
PCsat TLM:                10   14  (assumed 1 per minute)
PCsat Status:              4    5  (assumed 1 per 3 minutes)
PCsat Bulletins:           8   12  (assumed 4 per 5 minutes)
My packets digipeated?:    3    3  (I had two msgs loaded + my posit
Estimated pkts fm others: 21    5

S-meter segments:      Pass1     Pass 2
                       --------  --------
                       20% none  35% none
                       35% 1     18% 1
                       35% 2     18% 2
                       10% 3     25% 3
                                  4% 4
All sounded somewhat distorted due to doppler and fact that PCsat was
in RESET mode which defaults to high deviation.

CONDITIONS:  My RX set up is poor.  It is an untuned 5/8 wave magmount,
and attached to only a 1' square plate screwed to the PLASTIC roof of
my van.  PCsat was in RESET mode, meaning its deviation is HIGH (wider
than passband in the presence of doppler).  I was set to the suggested
parameters for a D700 under "special" conditions.  Meaning my Posit
was set to 1 per 5 minutes.  And messages operate at a 1/minute rate
for only 5 minutes activated once in the middle of the pass.

CONCLUSIONS:  In both passes, my POSIT was digipeated.  In both passes
I think both of my messages were digipeated.  I did receive telemetry
at least 3 times in each pass.  Thus the mission objectives of
getting one's position/status out, and being able to upload a message
were met, even in my sub-optimum arrangement.  It was tough resisting
the temptation to transmit more often than the recommended timing,
but I did and it worked.  Notice on my 5/8ths wave vertical, the
OVERHEAD pass performance was WORSE than the horrizon pass as would
be expected.  The best antenna for PCsat will be a 19" vertical whip
on the mobile, not a gain antenna.

It would be nice to hear from someone with a D7 HT doing a similar test.

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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