[amsat-bb] Questions: Portable digital satellite station

["William Leijenaar" <pe1rah@xxxxxxxxxxx>]

Hi AMSATs,

In 1999, before I made the travel through Europe I had some idea to make an 
portable PACSAT satellite station, to keep in contact with home and other 
amateurs from anywhere in the world. At that time I face many problems, and 
finally I decided to make an portable SSB/FM station to work with via the 
analog transponders.

Now I have this station working, and I am thinking again to make the 
portable station that is capable of sending messages via the OSCARs. Still 
there are some unknown things that maybe finally can give problems at the 
end, so I like to gain some information first.

My major goal is to make an system that can send some small digital messages 
(just ascii text). The PACSATs can do it, but I am not sure about the APRS 
satellites. So my first question is:

Is it possible to send messages to one specific amateur via APRS satellites 
?
Is the couverage world-wide ?
(because the APRS satellites have no digital storage, when I'm right and 
then there must be some remote areas where the messages are not forwarded)

Then about the pacsats I have also some questions. This question I had also 
in 1999. Like many pacsat amateurs know, many packet networks are connected 
via the pacsats. When some (none satellite) amateur in e.g USA puts an 
message in his local BBS for some (none satellite) amateur in UK, then the 
message will be forwarded from an PACSAT gateway in USA to an PACSAT gateway 
in the UK via UO22 or KO25 etc. This works very good !!!

But the next version is still an problem:

I have tried to send an message directly to the pacsat and get it via an 
gateway to an local BBS, but this is not working !!!! I tried many options 
but the gateways don't recognize me as an gateway and do not forward my 
message stored UO22 or KO25 to the local BBS. (I like to have an message 
link, directly from satellite station, via an pacsat, via an pacsat gateway, 
to an bbs on earth)

Maybe someone knows how to do it ?
Maybe the system can be changed so (portable) pacsat stations can make 
advantage of this system ?
--> Only one gateway station that captures the (portable) pacsat messages, 
and reflects the message back on the satellite as a gateway would be enough 
!!! The message would have some delay, but that is better than no message at 
all.

Then I am looking forward to some information about the recieving of the 
pacsats with 38k4 downlink. I can hear the signals but I have no modem to 
see how good the signals can be recieved. Is the BER (bit error rate) better 
compaired to the 9k6 packsats (KO25,UO22,KO23,TO31) ? Do I need a more 
sensitive recieving ??

See you on the sats,

73 de PE1RAH, William
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