Have you tried this?
My observations were that a ferrite on the cable between the RPi and RTL significantly reduce the message count.
Perhaps this says something about the quality of the USB cables I had, but it’s worth keeping in mind.
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Do you have some graphs to show how your filter setups work together with your RTL-SDR dongles?
A comparison between the Ceramic and SAW on their own and with the 3 pole cavity filter together perhaps?
The final setup will be in an outdoor enclosure on a pole, I will be making that enclosure a cage of faraday so hopefully the part of making the filters/dongle/Pi interference free should have been taken care of then.
Also with the ferite beads and propper groundings will be applied then.
So I am more concerned about the things the antenna will be picking up.
I have indeed also been looking at the filter you mentioned.
However it has quite some punch in a little package, which is not neccesarily a bad thing, but the overall what I have been reading is that it becomes really warm.
As an avionics guy, I don’t really like “HOT” electronics 
All will be in an outdoor waterproof enclosure, so I prefer something that doesnt get to hot on its own
Or is your experience with the RTL-SDR LNA heat thingy different?
RTL v3 dongle becomes quite a bit hotter in comparison.
From the comments on the product page written by “admin” i presume the designer:
Regarding your 960 MHz noise and the rtl-sdr blog LNA:
P.S.: In case you are looking at my stats i am limited by terrain in all directions and even the best direction is not completely unblocked.
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@geckoVN,
Yes, I have ferrite cores on all my 6" USB cables. I use quality USB 3.0 cables just to be sure.
The same goes for the power cable.
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Did the run myself, i had a blue flight aware stick and it failed so as i had a FA filter i just bought the orange FA stick, should i put it in place?
here seem to be my problem areas, and here 1090 looks weak although im achieving 150nm i think i could do better.
The external FA filter is very different from the internal filter of the pro stick plus. (the internal filter is much better)
To see how to proceed with filter I ran this this morning. The setup is a RPI 3+ attached to a Orange FA then the FA filter and on to a roof-mount outdoor antenna (Jetvision A3).
Without the filter (just orange stick) the spectrum is entirely yellow. And in fact, the local traffic at gmap.html has 1 plane on it. Entertaining.
With the filter in place it looks much better.
Still plenty room to to make changes to filtering.
The set up is the following: Raspberry Pi 3 connected via FTP cable to a router, Prostick Plus with the lightblue FlightAware filter (it is the first that came out), running 10m cable to a FlightAware antenna. There is a mobile basestation (cell) nearby. Is there a need for something more, or the filter is doing its job fine?
If the range is good i wouldn’t worry about it.
But most likely the dark blue filter or using an external LNA might improve reception.
(Light blue filter is not that effective at 950 MHz)
Very hard to predict if something will improve reception though.
This is the Piaware station I am talking about:
https://flightaware.com/adsb/stats/user/rosen85#stats-41572
This is the range in VRS. The red dot is the feeder location.
That’s quite good range, i doubt you would gain much or any range with another filter.
If anything i’d probably turn the gain down a bit.
(Looks like reception short range might be reduced due to oversaturation)
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Alright then. Now there is another question: How to check the right gain settings?
By trial-and-error, watching RSSI column of dump1090-fa, sorting high to low & low to high by clicking column heading.
Lower gain if number of messages > -3dBFS are large.
Also install graphs. The top most graph has “% messages > -3 dBFS” in bottom margin
Graphs for dump1090 – my version with install script
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What about if number of -3dBFS messages is 0?
Should I increase the gain or not?
I suppose I should continue increasing it until the number of the -3dBFS messages goes up?
There is no hard and fast rule. Mine is 3.9% as you can see from my graph in previous post, and I am happy with it.
It is a compromise between max range, and nearby plane droping off due to overload
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On second thought, it is possible that your figure is zero because you have installed graphs an hour or two ago, and it is dividing the 2 hour’s collected data by 24 hrs to get the average figure.
Wait for 24 hrs and see.
What is the reading on 1 hr graph?
This raises the question of your particular goal.
Some want to see all the aircraft nearby coming and going from the local airport and don’t care about aircraft at 200NM. I’m more interested in seeing as many aircraft at as great a range as possible and don’t care if I miss some reports from planes close by.
Each to their own.
S.
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That’s exactly why I have two separate setups.
One for long range and the other for close in.
The gain for each is set accordingly.
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