When I receive AirNav’s Red (978 mhz) dongle, I will carryout an RF Scan by my $25000 Spectrum Analyzer NOSE 
Source and post results. Of course these results wont be accurate, but some graph will be better than no graph.
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About Flightstick978
https://www.radarbox24.com/flightstick978
About dump978-rb
Scroll down and see item 8 on this page
https://www.radarbox24.com/flightstick978/guide
I am not sure… I didn’t include the 3 dB points on purpose since I don’t know the bandwidth of a UAT signal. I am guessing it is between 1 MHz to 2 MHz but that is a WAG on my part.
Is NOSE an acronym for something?
I saw the graphs in another post!
Please see the spelling of name written inside the red rectangle: 
It is actually NOISE SOURCE, misspelled.
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Ha! I like it! Very funny!
I learned something new today! Thank you!
PS - I see you add a period to add some whitespace. If you prefer pure whitespace you may want to use this:
It may not work in the wikipedia quote, but it should work every where else on the forum.
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Thank
you
for
the
tip.
show off! 
Changing topics slightly… I was thinking about filters and some of the “noise” (not nose) that I see at 960 MHz. I unscrewed the antenna, added a 50 Ω terminator to the receiver, and ran rtl_power. But the signal at 960 MHz did not disappear. So I’m guessing a filter will not help with that!
Does anyone know what is generating the 960 MHz signal? I’m guessing it is within the orange FA Pro stick.
EDIT: Added image of scan with no antenna and just a 50 Ω terminator:
If you have another dongle, run the scan on it with 50 Ω terminator.
If 960mhz spike is still there, then it is unlikely that both dongles will have same defect, and most likely it is generated by some other appliance in vicinity, or by the RPi itself.
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Nothing to see on the RTL-SDR v3 dongle with 50 Ω terminator.
rtl_power -d 00000978 -f 800M:1200M:100k -i 30 -c 50% -e 30m -g 30 -F 9 > scan.csv
Does v3 has a builtin LNA and Filter?
May be for ProStick, -g 30 is too high due to it’s builtin LNA. Test FA dongle at -g 20
I have a FA pro stick plus + 8 segment coco + 15ft RG6. Here are my results. Would a filter be justified and can anything be done to improve signal around 1090, or does this look normal?
Additionally, would the Uputronics 1090MHz ADS-B Filtered Preamp be a good choice? This would need to be placed directly after my receiver.
Your scan shows that your antenna is receiving Cell Phone band GSM850. Adding a 1090 mhz filter will get rid of Cell Phone’s GSM850 signal, and most likely improve reception of ads-b 1090 & uat 978.
I don’t believe it does. There was nothing mentioned in this data sheet.
I’ll give it a try!
EDIT: added image from test…
Scanned orange FA Pro Stick with just a just a 50 Ω terminator instead of an antenna. A bit cleaner with 10 dB less gain. But at 20 dB of gain I probably won’t receive too much when connected to an antenna.
rtl_power -d 00000978 -f 800M:1200M:100k -i 30 -c 50% -e 30m -g 20 -F 9 > scan.csv
Wrap the FA ProStick in aluminum foil (to shield it from any local signal generated by rpi or any nearby appliance), and again perform scan at -g 30. Hopefully the 960 mhz spike will disappear. I understand v3 has a metallic casing, am I right?
Hey! Quit looking at my workbench! I’m secretly trying to create a small faraday shield!
Yes. Aluminum case I believe.
I found another one here but it is out of stock…
https://www.rtl-sdr.com/product/spare-aluminum-metal-enclosure/
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Planefinder. Three SAW filters
https://forum.adsb.in/f4/uuoy-novovoronej-kaput-2193/index2.html#post48330
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