I am having a PI 3b+ setup running for 1 year now, with LMR195 cable (6meters) and FA antenna outside on a mast and few converters from N connector to SMA
Stick is FA blue, gain is 49
After updating to Piaware 5 (not sure this was the problem) traffic dropped from 250+ Nm to maxim 100. There is airfcraft traffic, i’ve checked other installations.
I had a lot of rain lately (raining since 1 week now) and i went and brought down the antenna, removed connectors , blew them with a hair dryer and let them sit for 1-2 hours .
Antenna was also having some pressure noise like when you open e pepsi can but not fully so you can hear some hissing.
I also left the antenna on the house heater near my window, put all back together but still no joy
- check the cable for shorts with multimeter, all good
- used a different dongle
- used a different power supply for PI (both tester and original are original PI power supplies)
- installed Piaware from scratch with SD card image, still nothing
The only thing remaining is to use a different PI but i only have a RPI 2 which is very old
This PI is also running with no errors or problems, it has a cooling sink from Pimoroni , temp never went higher than 45 degrees C.
I can only guess that water got in near the cable SMA connector inside the covering sleeve and increased the impedance/resistance to very high because comparing the RSSI of planes now, i can see a +10-12 dB drop on planes that are near me, when before i’ve seen -4 dB, -4.5 on these planes, now i see -14, -15 maybe higher
here is the current situation
here is how it used to be (green plot was max range)