Low loss or not its all about how high and open you can get your aerial.
HTH
Cheers John
So you use the RG174 coax and aren’t concerned because you have height?
I am not concerned with the RG174 it does what it is supposed to do.
If I put the aerial on my windowledge my coverage drops to about 20Nm with about 16 - 30 returns at peak times on the box both mode-s and ADSB.
By experimenting I have increased that to over 150Nm and 150+ at peak times.
I've taken my lapop up to my local airport and achieved a similar polar diagram
with returns of over 200. So the the radar box and supplied aerial do exactly what they should do and very well. The down side to this is the supplied aerial is not specifically for external use. Any loss in the supplied aerial is not really a factor because the range that can be achieved is far greater than I can physically see.
Where are you located, whats your nearest comercial airport and are you supplying the network because I am curious to see what kind of traffic your getting.
Cheers John