Yesterday and today I have been investigating why one of my sites had a drastic performance drop.
The issue started very abrupt and I couldn’t explain why.
Around 6 PM this particular site dropped back to only 10% of what is normally picks up from the skies.
So I started investigating the matter since this is unusual behavior.
It’s neighbor that is overlooking the same sky didn’t have the problem so we could rule out any external factors pretty fast.
So might is be the software then ?
No error reports, normally reporting on the 3 aggregator sites I’m sending the data to but they all are working fine.
So software isn’t this issue the, it has to be the hardware.
Shutting down the receiver, checking the dongle, LNA and Filter revealed a wonky connector between the dongle and LNA.
When opening up the LNA it became clear that the SMA connector from the LNA towards the dongle wasn’t connected to the PCB anymore.
Replaced the LNA with a spare (having spares is a habit I’ve made since I entered this hobby 8 years ago) and the site went right back to where it was supposed to be.
Soldering iron out, fixed the connector again to the PCB and it is working normally again. Disconnection of the connector is either because it wasn’t soldered properly in the factory or mechanical stress. The mechanical stress part has been dealt with so that shouldn’t be an issue anymore.
So why is monitoring your site important then?
The site operated normally in the eyes of the receiving sites (FA, FR24, Airnav) but the traffic rate went back to 10%.
This is not a factor that any of the sites will raise a flag for.
Without the use of Graphs1090 I wouldn’t have seen the issue very quickly.
Indicators were:
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Raised gain. The gain went up to 49.6 and that’s abnormal when you operate a dongle with a LNA attached to it.
Message rate imploded
Number of aircraft seen went to 10%
Range drastically dropped
Without the use of Graphs1090 this wouldn’t have been very obvious to see so.
So if you are running a site, do yourself the favor of installing Graphs1090 along with it.
I will give you valuable insights into the inner working of your system and it helps you to get a better picture of what is going on when something odds happens.
