[amsat-bb] Re: PcSat-1 Bulletin Question
Robert Bruninga
bruninga at usna.edu
Mon Oct 2 10:41:27 PDT 2006
> I see a PcSat-1 bulletin I do not understand.
> BLN2PCSAT:Aliases are R,W,Wn-N,Tn-N & ARISS
> I understand ARISS. Can you tell me the meaning of the other
aliases?
Yes, PCSAT-1 acts just like any terrestrial APRS digipeater. So
we wanted to make sure it would respond to any path that is
typicallly used by terrestrial users so that all they had to do
to use it was to change their frequency, and not have to also
change their path.
So PCSAT-1 was made to respond to all of the existing and legacy
paths that are used on APRS. They are:
RELAY
WIDE
WIDEn-N
TRACEn-N
and ARISS
And we are seeing many people using a variet of these paths.
HOWEVER, there is a problem when people use the WIDEn-N and
TRACEn-N paths, since these are decremented at each hop. Thus,
a WIDE2-2 packet digiepated by PCSAT-1 will appear as
...PCSAT-1,WIDE2-1 and will not indicate the PCSAT-1* until the
final hop. In this case, there is only one hop and so the
FINDU.COM web-page that parses all APRS traffic looking for
packets via PCSAT-1 will not see them because it wont see the
PCSAT-1* marker.
If people want to keep track of their success on FINDU.COM (
http://pcasat.aprs.org ) then they should not use a n-N path and
should change their SSID so that their station call is unique
for this space application. Otherwise, as soon as they use the
same station again on terrestrial APRS, then the posit via the
satellite will be overwritten.
Bob, WB4APR
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