[amsat-bb] Having Issues with UISS/Soundmodem for ISS contacts.. (Long)

JoAnne K9JKM k9jkm at comcast.net
Tue Feb 14 19:04:15 UTC 2017

Hi Steve,

 > ... 3 memory channels in the 9100, one low, one center, and one high on
 > the ISS 70cm side. (437.500, 437.550, & 437.60)

You need to adjust your tuning steps separately for TX and RX for 
Doppler correction. Your current configuration is taking to big of a 
step. Patrick WD9EWK made a list of 5 Doppler corrected frequencies 
which he stores in memory. As the orbit progresses over your QTH start 
with Memory #1 and work your way on up through the frequencies in 
memory. He has a graphic file of his frequency table posted at:


Patrick's recommended steps work well for me. I find I spend only a 
little time on memory slot 1 and slot 5. Memory slots 2, 3, 4 are what I 
end up stepping through most often during a pass.

Also, packet routing add-ons such as WIDE, etc. are not needed. CQ VIA 
RS0ISS or CQ VIA ARISS keeps your packet short, less error prone, and 
more likely to be digipeated.

I'll be looking for your callsign via the ISS (although toward the east 
I have a pretty big obstruction but I sometimes get through it).


73 de JoAnne K9JKM
k9jkm at amsat.org

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