I bought the blue FA Filter as addon to my blue FA stick (pro plus) and it turned out that the performance did not increase with filter. So it always depends on your individual environment causing noise. Many might need it for better results, some (like me) not.
And for the cable it depends if antenna or satellite.
I was running my installation with a five meter extra shielded low loss sat cable without issues.
What about RG6 coax used with Satellite Dish TV? Satellite TV channels are in GHz frequency range, and the RG6 coax is designed for this frequency band
The Generic DVB-T is designed for TV (Digital Video Broadcast - Terrestria), and as TV systems use 75 ohms antenna & coax, it has an input impedance of 75 ohms. The specialty dongles like ProStick and RadarStick have a LNA chip which is 50 ohms.
That said, the reflection of power caused by 75 to 50 impedance mismatch is significant when transmitting, as powers involved is in tens or hundreds of watts. In receiving senario, powers involved are mili or even micro Watts, and losses are easily compensated by front-end amplifier of the receiver.
The 50 to 75 ohm mismatch causes SWR to change from 1 to 1.5, and power loss of 0.177 dB only.
Whether or not you need a (additional) filter is not a question anyone else can answer for you (except perhaps your next door neighbour).
As you already have the filter, try with and without for (say) 24 hours each and see how it performs.
While satellite TV works on, for example, 10.7 to 11.7 GHz and 11.7 to 12.75 GHz, the signal from the dish to the house has already been down-converted to a much lower frequency. The so-called “LNB” is a filter, amplifier and down-converter.
The output from the LNB usually spans 950MHz to 1950 MHz and 1100MHz to 2150 MHz. Any cable which performs well in this XapplicationX frequency range will be great for ADS-B reception at 1090 MHz (or 978 MHz for that matter).
As said by @abcd567 Satellite TV cable is very good for 1090mhz operations, can be used also for VHF/UHF airband with very good results, on a par with far more expensive coaxial cables, economical too. See first section of this post in my blog site.