[aprssig] Good Propagation = Poor APRS Performance?

Tom Hayward esarfl at gmail.com
Thu Jul 16 18:10:09 CDT 2015


On Thu, Jul 16, 2015 at 3:05 PM, David Andrzejewski via aprssig
<aprssig at tapr.org> wrote:
>
> So, I've been noticing that not all of the packets being transmitted by my home station (KD8TWG-1) are being picked up by local digis and igates regularly like they normally are.  I've done my best to check my station - antenna and feedline are good, radio power is normal, SWR is minimal, radio is on frequency.
>
> Then I noticed that propagation around my area (Clevland, Ohio) has been really excellent lately according to this map: http://aprs.mountainlake.k12.mn.us/.  Would it be a good assumption that because of the good propagation, the local digis are simply getting overloaded?  Or should I do more troubleshooting on my equipment?  I should note that my Kenwood TH-D72 hears and decodes every single packet from my station perfectly, but it's obviously very close to the antenna.

Yes, that's exactly it. Since APRS is half-duplex and all on one
channel, it works best when digipeaters have minimal coverage overlap.
This keeps the channel clear so when your station transmits, it can be
heard. When propagation is better than normal, those digipeaters that
were designed for minimal overlap now hear each other, leaving much
less clear air time for your packets to get through.

Tom KD7LXL


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