TLDR;
What stats can be reviewed for determining if any settings could/should be changed to increase coverage/distance?
Long version;
Single site mounted 12 feet AGL with pretty good “line of sight” in all directions and I’m not overly worried about the few “weak spots” seen in the coverage graph (known cell towers due North etc). https://flightaware.com/adsb/stats/user/johnb0
A point in time from SkyAware 2020/12/7 22:05UTC:
Total Aircraft: 133
With Positions: 123
Messages: 812.8/sec
There’s another user within a mile of you who saw six more aircraft than you on December 7. Seems like there are 4 or 5 within a 5 mile circle who are in the same 1700+ range. It’s very possible that you are already seeing all of the aircraft that there are to see.
Have you checked out heywhatsthat.com? It can show you a theoretical max range ring for various aircraft altitudes, that you can compare to what you are receiving. It doesn’t know about trees or houses, but does a pretty good job with terrain limitations. Make sure that you enter the correct altitude for your antenna, then try varying that height to see if you can improve with altitude. Again, it may show you that you are getting what you get.
In my case, I have my antenna slightly above the roofline of my 2 story house - about 30’ AGL. If I were to raise it another 10 feet, for example, I wouldn’t gain much in max distance because the terrain that is limiting is so far away. For example, the Cascade Mountains start about 40 miles east of me, and limit my range in that direction. From my roof, they are about 10-15 degrees above horizontal. Raising my antenna 10 feet is going to make a rounding error of improvement to range. It’s even worse to my west, where the Coast Range is ~100 miles away.
Sorry for the extra-long response, but the point is that you may already be getting all of the planes that there are to get.
Thanks… I’ll be patient and wait for a week to pass
As for adjusting gain, it seems to have made a significant change in the positive direction. I set it from “max” to 49.6 and restarted dump1090-fa at 2020-12-10 0816CST