[amsat-bb] ISS Packet Frequency?
Stewart Todd Morgan
morgan_st at bellsouth.net
Thu Apr 27 23:23:48 UTC 2017
Yes, I can, but I'm not complaining about performance. The point of the
TH-D72A vs. IC-02AT test was to see if evidence existed to support the
notion that there might be some anomaly with the new ISS APRS system
that might explain why some operators (Scott, K4KDR and others
apparently) are unable to decode packets now when they could previously,
either on 70 cm or 2 m. If my comparison test had come up, say, 13 to 2
packets decoded in favor of the TH-D72A, that would lend credence to the
notion that such an anomaly might exist but is masked by the better
performance of purpose-built (i.e. designed for packet/APRS) equipment
like Kenwood and Yaesu transceivers.
When you have a measure of experience with something like ISS APRS
reception, it's easy to brush off reports like Scott's and just chalk
them up to operator ignorance, operator incompetence, simply forgetting
a step or two in a setup process, etc. But Scott is asking for some
help (a sanity check), and I was just trying to perform a few
independent tests. There are plenty of other operators who could do the
So now the question would seem to turn to things like:
What do Scott's station and the others have in common (if anything)?
Are they all SDR type stations?
If they are SDR stations, are typical SDR stumbling blocks handled
properly (offset, center spike at 0 Hz offset, etc.)
Are the station components and transmission lines well shielded?
Have local interference sources come into existence on or near 145.825
MHz since the ISS was previously on that frequency?
On 4/27/2017 9:18 AM, Norm n3ykf wrote:
> Can you record the RF on an SDR and make multiple tries decoding?
> Norm n3ykf
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