Improved tracking due to cold weather?


#1

I don’t know if any other 'trackers are finding the same, but my rig is spotting aircraft from an extra 50 miles away today. The local weather is a bright, cloudless blue sky (compared with the usual Yorkshire Grey) and it’s very cold.

Anyone else?


#2

Weather conditions can affect range of reception. https://en.wikipedia.org/wiki/Tropospheric_propagation


#3

Yes, been very cold in my area of Canada, temps down to -30c, and get some decent range up to 300mi. Waiting for warmer weather and tropo season where it is possible to pick up signals from beyond line-of-sight (over the horizon). As a ham I’ve made some really long contacts in VHF and UHF due to anomalous propagation modes, so hoping we’ll see this on ADS-B frequencies as well.


#4

Propagation modes don’t stay around for long. Usually gone within a few hours. I have seen increased ranges in the 20% range but they rarely last long.

Just a quick question. Do you have the radio outside of an air conditioned room?
The radio’s internal noise goes down as it is cooled. This allows your site to see weaker signals which increases your range a few percent. It really isn’t too noticeable unless you have the radio much colder than normal room temperature.

I wouldn’t suggest you freeze your radio or put it outside. The radio components are rated to 0C but the gains aren’t worth the risk of damaging the radio.


#5

Ha! Too good to last - we’re back to traditional Yorkshire heavy clouds and my range has gone down again.

The radio is unfortunately in a very noisy (electrically) environment - my home office in the roof space - but the Pi is running at an average of 35c with an ambient temperature of 10c. That’s the best i can do for now and in the summer it’ll be as hot as hell up here so we’ll have to see what happens. However, I recently moved my aerial to the other side of the roof space where there are no computers and it’s improved somewhat and with a long network cable I may be able to move the Pi out of the Pi-stack to somewhere quieter.

In the summer I’ll be able to extend the aerial out through the roof space window t get extra range.


#6

Very cold here this week in Canada, around -25C, set a new record of just over 600Kms for a pick up, I’m usually max around 350kms.


#7

According to this guy, the theoretical radio gain is just a few percent due to the temperature drop.
http://www.setileague.org/askdr/cooling.htm

However, the cooling effect is definitely more noticeable than a few percent. The total gain due to propagation modes + lower noise levels + receiver adds up to quite a nice improvement.