I have been graphing my PiAware 30 day Site Ranking for several years.
Whenever we have a cold snap, (<~ 25 degrees F) I notice a large drop in my rank. (high rank number) When it warms up, my rank goes up (lower number) See
Any speculation? The antennae is on the roof of our building. The Pi is in an unheated utility room with the big circuit breakers and meters. I don’t think the room ever freezes indoors, but I have never measured it.
What do any of your other stats or graphs1090 tell you? You haven’t really given enough information to go on. 
What rank are you talking about? Is this the rank of your station at Flighaware?
Mine goes up and down every time, independent from the weather.
I have mine outdoor since more than two years and never had an impact like that. Temperatures are here between -10 to +40 °C (14F to 104F)
Is your device outside or just the antenna?
If outside, what are the temperature readings of your SoC?
The FA ranking depends on the traffic. Even a comparison with nearby stations is not 100% reliable because you would need a reference station with the same range, direction etc like yours.
For my region, aircraft count nearly doubles when the sun is out as casual GA aircraft make up nearly half the traffic when the weather is nice. Commercial traffic is generally steady by comparison unless we have extreme bad weather events.
You can see the recent nice clear day traffic peaks in my aircraft count graph below. The low traffic days in this graph had dense fog or rain. You should check the correlation of weather and aircraft count for your station.
Also, when humidity is low in the upper air in my region (not often in the winter months here near the ocean), my peak and average range increases noticeably as well which helps with metrics a bit. This happens almost all summer long, but also happened for a few days in late December when bitter cold and dry arctic air moved over the region.
Could have something to do with this:
Strangely the APRS VHF propagation map isn’t loading the propagation visualizations right now, I check that from time to time (other radio hobbies) and have found some correlation to UHF propagation/1090 MHz range for AC below maybe 30 to 35,000 feet. While tropo can do cool things for range for periods of time, especially lower aircraft, I don’t think it significantly impacts total aircraft or messages metrics through days for most stations. But I suppose it is possible.
I can see that my 30-day stats position is going up and down, hovering around 200 positions
And that happens even with exactly the same values on a day per week for these 30 days
So to me it seem to be that the stations which are in the stats around me are getting better or more worse from time to time.
This topic was automatically closed 365 days after the last reply. New replies are no longer allowed.
