Ok, The gain settings for the RTL-SDR was -10 for AGC with max aircraft range 150nm. Other stations in my area can pick up more in average, like 200-250.Now at the moment I have set the gain to 29.3. Its clear that the Pro Stick Plus is not accepting the -10 value, or I am wrong? I still do not understand why the windows laptop usd port does not recognize the Pro Stick Plus. There is no USB problem that I know. RTL-SDR is recognized normally along other USB devices.
-10 works fine with the dongle. Chances the frontend is overloading are high though. That will lower the performance.
When I plug a blue FA stick in my laptop, it shows an unrecognized RTL2832U device. ie. there are no windows drivers for it.
Try to install the Zadig driver for Windowzzz.
Why should it not?
If i change mine to ā-10ā i completely overload it with my Jetvision Antenna.
29.3 is very low, you might need to play around with the settings.
With a passive antenna and no other LNA in between, values between 40.2 and 49.6 should be worth to test it.
40.2 to 49.6 are the values I normally use with a Jetvision+FA filter+ProStick Plus, if I remove the filter I get 0 positions and 0 planes.
The Prostick Plus includes filter. Why are you using extra filter?.
When I set -10 with my homemade colinear antenna (calulated at 9db - not tested) I get 0 planes. So the logical thing to do is to start from 49.6 and gradually decrease the gain.
The preamp in the ProStick Plus can be overloaded by out of band signals. The filter is after the preamp. Adding an external filter can eliminate the problem.
See this recent thread:
Download Graphs1090 - Aim for strong messages (under 3 dB) lower than 5%
Then you live in a difficult environment. I have here the dark blue filter, but it doesnāt change anything if i am using it or not.
My gain is set to 42.1 which is here the best option.
Normally yes, but some have issues because of the environment. Then an additional filter will help.
-10 with no planes on a 9dB Antenna sounds like heavy overload.
@foxhunter probably I have all kind of antenna close by 
check this test acquisitions Iāve done.
As saidā¦ it heavily depends on the environment.
I am in a lucky position here in Germany with almost no interference from other signals like mobile network.
For me it doesnāt matter if i am attaching a filter to my setup or not.
The blue ProPlus stick with a Jetvision antenna delivers the max.
As we do have ADS-B only, i do not need to filter on 978MHz
Everybody needs to test it against itās own environment. There is no solution that fits all.
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I wanderā¦ is it necessay, every time I change the gain to reboot the PI?
No, you donāt need to reboot when changing gain, just restart dump1090-fa.
I understand the kernel detachments @obj mentioned, but what I fail to comprehend is that if you followed his instructions as written and pasted chronologically, the dmesg log wouldnāt have included the stop and restarts at the time you ran it. This is what leads me to conclude that under normal circumstances, your radio was dropping out. Perhaps you ran the tests more than once and pasted the second or third go-aroundā¦
At either rate, without dwelling on USB power issues that always seem to crop up when using Pi Zeroās and FA Orange/Blue, if you were running -10 gain with the RTL-SDR blog radio, the FA Plus should be working fine in the ~38.6dB gain range all else being equal. But, as many mentioned, the FA Plus is very prone to frontend overload, so adding a filter in front of it may be the answer as @LawrenceHill linked. Iām trying to figure some things out before you end up spending more moneyā¦
Very good idea and is free. What do your graphs look like?
No, it is not. Simply restart the process with
sudo systemctl restart dump1090-fa
afterwards you can check if the settings are taken with
sudo systemctl status dump1090-fa
If you installed graphs1090 what was suggested by @carstenks you can leave the gain for a while and check the results.
But be aware that you need to have a considerable traffic. Otherwise the results will be more random than comparable
I ran the test only once.
Trying different gain settings I noticed than any value above 30 is making the reception worst. Should I try more powerful power supply?
Well this could be overload/signal saturation, but trying a different usb cable between the radio and PiZero and/or power supply is also worth a shot if you have something laying around.
Also, I believe that setting max_usb_current=1 in the /boot/config.txt file is still a relevant setting to increase the USB port power cap on the Pi Zero if you havenāt already done so (needs a reboot after).
What does graphs1090 show? Also you never completed the āsudo rtl_test -s 2400000ā test as it appears you cancelled it early according to your earlier C&P. Need to let it run for about 30 seconds at least. Iād try that again prior to and after cable/PS swapping to see if any change on that front.
Your location may very well require a filter in front of that FA stick regardless, but best to rule out underlying hardware constraints since the Pi Zeroās are super picky in my experience, especially when stabbing a radio in that needs the extra power for the LNA. Iāve been down this road in the past with the PiZero, so thatās why Iām so focused on the cable/power thing first.
I replaced the power supply with more power and the cable with a more rigit one
I ran the test for 30secs before and I repeat it again:
------ for 30 seconds-----
pi@piaware:~ $ sudo rtl_test -s 2400000
Found 1 device(s):
0: Realtek, RTL2832U, SN: 00001000
Using device 0: Generic RTL2832U
Detached kernel driver
Found Rafael Micro R820T tuner
Supported gain values (29): 0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6
[R82XX] PLL not locked!
Sampling at 2400000 S/s.
Info: This tool will continuously read from the device, and report if
samples get lost. If you observe no further output, everything is fine.
Reading samples in async modeā¦
Allocating 15 zero-copy buffers
lost at least 64 bytes
^CSignal caught, exiting!
User cancel, exitingā¦
Samples per million lost (minimum): 0
Reattached kernel driver
------45 seconds -------
pi@piaware:~ $ sudo rtl_test -s 2400000
Found 1 device(s):
0: Realtek, RTL2832U, SN: 00001000
Using device 0: Generic RTL2832U
Detached kernel driver
Found Rafael Micro R820T tuner
Supported gain values (29): 0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6
[R82XX] PLL not locked!
Sampling at 2400000 S/s.
Info: This tool will continuously read from the device, and report if
samples get lost. If you observe no further output, everything is fine.
Reading samples in async modeā¦
Allocating 15 zero-copy buffers
lost at least 84 bytes
^CSignal caught, exiting!
User cancel, exitingā¦
Samples per million lost (minimum): 0
Reattached kernel driver
---------60 seconds-----------
pi@piaware:~ $ sudo rtl_test -s 2400000
Found 1 device(s):
0: Realtek, RTL2832U, SN: 00001000
Using device 0: Generic RTL2832U
Detached kernel driver
Found Rafael Micro R820T tuner
Supported gain values (29): 0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6
[R82XX] PLL not locked!
Sampling at 2400000 S/s.
Info: This tool will continuously read from the device, and report if
samples get lost. If you observe no further output, everything is fine.
Reading samples in async modeā¦
Allocating 15 zero-copy buffers
lost at least 64 bytes
^CSignal caught, exiting!
User cancel, exitingā¦
Samples per million lost (minimum): 0
Reattached kernel driver