Built a new station from an old Pi3B and FlightStick, and trying out different antenna and locations. Will bounce up and down as I do. Stormy out at the moment though, so not today.
Clear view to the horizon from West to NW, and getting aircraft out to 400-500Km on the approach to Auckland International. Hills about 2 degrees up in other directions, and mostly blind in these directions, so will try to get higher. Just needs some power further up the hill.
You get good range out over the sea with nothing to get in the way
Alan
Yes, the house has a great sea view, from West to almost NW (305), and I have had signals out to 250NM with the antenna sitting in the window. The house has a poor view in other directions though.
Moved 40m up the hill to small shed, gaining about 10m altitude, but then getting a slightly worse angle to the NW lane. Here I've seen out to 262NM directly West at flight level 400. I've seen 255NM to the WNW, but there is a gap between ~170 and ~200.
I can move even further 50m up the hill to my comms tower, gaining another 10m , and have a better view to the North, but this will reduce my NW sea view slightly. I need to run a new cable to test this location.
I can also get higher to the North East, gaining another 20m, but it would be a very long cable run. I might be able to run off batteries and solar, and wifi back. I would be looking down on the comms tower.
Precariously mounted ground plane antenna using 32mm conduit, and getting good range to the NW now, and better to the WSW. Still on the shed, where there is power and network.
Put the FightStick close to the antenna and ran 10m USB cable to the pi effectively getting an active antenna. Tests with even short lengths of LMR400 were quite lossy, and worse than they really should be. The cable has been in my shed for some years, so I suspect a bit of corrosion, even though a cable test shows them to be ok.
You are getting good results with your trials
Alan
Offline to make some changes.
back on, but sitting on the wall while I sort out a new location to test.
Its doing ok located there
Alan
Despite the large metal bracket right beside the antenna :). It was nearly as good sitting in the house window, and the house is 10m lower.
When it was about 3.5m above the shed, I got better coverage North West, through East and around to the South West. It was just on a couple of sections of 32mm plastic conduit, and was swaying in the wind. With the storm coming, it needed to come down.
I want to try it on my comms tower. I don't want to disturb the existing services on the tower though, so I am sorting out an enclosure and a new run of ethernet cable, so I can use PoE to the Pi. I have everything I need, but the weather needs to cooperate.
The range has been less during the last few days. We have had a lot of rain, and I have been getting line of sight distances (estimated 220NM). In slightly better weather, I was definitely getting refraction over the horizon and seeing about 50NM more than I should.
Can the pi keep a copy of what it is sending to radarbox in a local log or DB?
It would be helpful to plot the distance and direction for the station as I move the antenna about.
It would also be interesting to record the change in the atmospheric refraction over the year, and against the weather. Such tables exist for microwave links up and down New Zealand, but not out to sea.
I look to be going offline every now and then, but the aircraft movements are still being shown. Then the offline status goes away, and the status graph shows green again, as if I was never offline. Seems to be increasing in frequency, so I have restarted the rbfeeder
Unfortunately I dont have a good enought knowledge of Linux to answer your logging query
Alan
I'll find a way.
Down at the moment anyway. Had gales yesterday, which took out our power and closed the airport for a while. Power is still out. ~80Knot winds. House was shaking. Lots of lightning and huge hail.
Got power back. Didn't come online immediately though. The Pi couldn't see the FlightStick until I unplugged and plugged it back in.
The pi clock was way out too, though it did sync back up a shortly afterwards.
You are getting some fearsome weather!!
Alan
To answer my earlier question on keeping a local copy of the data during testing.
apt install netcat-openbsd
Then to dump the SBS messages via
nc 127.0.0.01 30003
dump1090 code is on github, and it looks to be serving the data to anyone connecting this port. It also dumps a different format to 30002 to any process that connects
All over the top of my old head
Alan
Lots of problems with my station just stopping sending data. It doesn't show offline, as the Pi is still running.
The FlightStick disappears from the USB. i.e. lsusb stops showing the FlightStick, and either unplugging, and replugging it, or a reboot of the Pi fixes the issue.
Sometimes it can still see the FlightStick on the USB, but still no data is sent. Again, unplugging and replugging, or a reboot helps.
I thought this might be the USB cable length, but it does it with the FlightStick directly plugged into the Pi too. Could be a software issue.
Also wondering if it is heat related. The FlightStick runs very hot. The shed is only 15C though, so should be cooling it better than a summers day. And it works again, with no cooling down period.
No ideas from me, sorry
Alan
Run a new PoE ethernet to the comms tower for a test. Gained 15m in height. Lots of metal poles around the antenna though, and sitting between several microwave links.
I'll have to watch for a while. First impression is it is better on 274 and 229 by 50NM. The Northern and South West, which are both behind ridges, our now out to 50NM. Better results from passing light aircraft and low flying helicopters too.
In the previous location, the variation in distance has been quite a lot though. It is very weather dependent, so it is hard to get a good comparison.
Not a bad spot. Might make this permanent (for now).
Bottom phot shows close to 270 View from the tower. The bit that is missing is a big hill.
Goodness, some metal up that tower!!
Alan