The LNA is working. Look at the signal level stats.
Which LNA is it? My Uputronics gets overloaded easily, however, I suspect the the airspy would handle it better than a V5.
My airspy isn’t working at the moment so I can’t check my stats.
Can’t you just lower the levels manually?
Yes I can do that, but I started this experiment looking at the new readsb autogain for RTL-SDRs, so I wanted to compare with the auto gain in airspy_adsb. I will repeat the test with the LNA, and if I get the same result, I will try low manual gain settings on the R2 and see what happens.
So you have part of that graph labeled R2, that means R2 without LNA?
It shows plenty of signal.
Thus LNA is not working with the R2, note the loudest signals are actually reduced for LNA + R2 compared to R2.
At the same time it seems to add a lot of noise.
I’ve repeated the test with the LNA returned to the setup. The results were different this time. To begin with it looks like the previous chart, but then after about 25 minutes airspy_adsb autogain reduces the gain setting and the results improve. After letting it run for about an hour, I’ve set fixed Gain =14 as suggested by @jonhawkes2030 .
Not even sure it’s intermittent. The autogain uses RSSI and with enough noise it might not reach the threshold for the gain to be adjusted downwards.
So it could just be a noise induced misbehaviour of the autogain.
And the noise would be caused by strong out of band signals yes. Which explains why reducing gains improves reception.
The graphs confuse me a bit as they show data in the airspy graphs while using hte LNA+v5.
I use an Uputronics filtered LNA with an Airspy mini on my main feeder. The setup described here is just cobbled together from my spare parts box, so it is definitely an edge case.
The longer term plan is to use the R2 with some sort of wideband antenna to explore other parts of the spectrum - airband, etc. Hence the wideband LNA and no spare 1090 filter.
Re the airspy graphs when using the LNA + v5. I think it is just visual confusing as the two don’t actually overlap (last seven days)
