[amsat-bb] Scott's Igate

Roy Dean royldean at gmail.com
Mon Sep 18 20:57:01 UTC 2017

> Dopler shift
> APRS-IS is throwing away your packets Andrew

Andrew, it is NOT doppler shift.   That has nothing to do with Scott's

Scott, the reason is because Direwolf required one flipped bit to fully
decode the packet (ie, it didn't "hear" the correct bits, but tried
flipping each single bit until what it decoded passed the checksum).   That
"[SINGLE]" means that it swapped a single bit to get a correct checksum.

Direwolf WILL NOT pass ANY packets on to the APRS-IS unless it completely
decodes the packet correctly (ie, that section should say [NONE], as in "no
bits were flipped in order to get the checksum to work).

Hope that makes sense.


>* On 19 Sep 2017, at 5:45 am, Scott <scott23192 at gmail.com <http://www.amsat.org/mailman/listinfo/amsat-bb>> wrote:
*> >* Hi everyone.
*> >* I've been trying to improve the effectiveness of the SDR iGate that I have
*>* listening on 145.825 and am finally seeing more packets.
*> >* Since duplicates don't show up on ariss.net <http://ariss.net>,
that explains why not all my
*>* received packets show up on the website.  Just for my own education, I'll
*>* often compare what my iGate receives from the ISS or PSAT to what shows up
*>* on ariss.net <http://ariss.net> to verify that mine are in fact duplicates.
*> >* Today on a PSAT pass I noticed that one of my received packets was a
*>* duplicate (which is fine) but the other packet that I received was also NOT
*>* on the website.  So, now we're not talking about a duplicate - it didn't
*>* get accepted to the site for some other reason.
*> >* Here's the packet as I received it.  I'm guessing that the issue
is that it
*>* wasn't digipeated by a station ID of "ARISS*", but I'd like to know for
*>* sure.  If anyone is really good with APRS in general or the APRS sat
*>* digipeaters in particular, I sure would appreciate hearing from you.*

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