I would be hard setting your gain to 42.1 and give it a look from there.
I tried uninstalling tar1090 since apparently it installed readsb.
My setup bricked.
Starting over.
What a waste.
We didnāt lose interest. Just wondering where you are at in your recovery process. Are you back in the game or sitting things out and trying to regain your composure?
Iām giving graphs1090 time to build data. Plus, Iāve had family in town all weekend.
Hopefully post graphs tonight, if my son doesnāt sap all my energy!
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The 1090 graphs can help a lot and keep you from feeling like you are walking around in the dark. Sounds like you have your hands full and life is keeping you especially busy. The smiles your son provides you will provide some of the extra strength you need to carry on.
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This morning I updated to PiAware 9.0.1. It seems to have changed something. At some point, one of the āenhancementsā I was trying to do must have screwed up the SDR settings, though I have no idea what nor why it would drop like before in the middle of the day when I was at work and couldnāt change anything (no VPN from work to home).
Anyway, here are the graphs from the reset, from where I was playing with it the other night, and with todayās upgrade to 9.0.1. Gain is set to 49.6 for the moment.
Could you please remind me of what antenna you are using, how high it is, what coax you are using and what antenna interface you are you using? Would you consider your Nov 13 graphs ānormalā for your location or is it still under performing?
Itās the Flight Aware 61(?)cm 1090Mhz antenna about 16 ft above ground with 50ft LMR400 cable to the FlightAware ProStick (blue) with a FlightAware 1090Mhz filter. That all goes into a Raspberry Pi 3B+ in my basement. The ADS-B antenna is co-located with my TV antenna.
November 13 is definitely closer to ānormal.ā I sit between KCMI and KMCK, both of which have a fair amount of traffic. If not for trees and buildings, Iād have a direct line of sight from my antenna to KMCKās ramp.
Itās my intent to get the antenna about 6 to 8 feet higher so that it fully clears my roof line and chimney, as well as any roof of the adjacent houses. That was the reason for 50ft of LMR400 instead of 10m (33ft) of LMR240 that I had before. This will also allow me to raise my TV antenna 2 feet from its current position (which is all the cable I have for it).
Your equipment certainly seems up the task, but I am curious about the co-location of your TV antenna. What is the configuration and separation there? The plan to raise your ADS-B another 6-8 ft to clear your roof line is great and maybe the detail of that move creates an even better separation from the TV antenna.
Theyāre separated vertically by about a foot.
IIRC, Iāve seen in another thread somewhere that the ideal minimum distance to another metal object is about 20 inches. I may also want to put up a cross-beam that further removes the antenna from the metal mast (and which gives me a place to someday hang a UAT antenna). The mast is made from a chain-link fence top rail, so I need to spend a few bucks for one of those, and also figure out some kind of plastic/composite/wooden cross bar to attach to the antenna. Then I just have the pain of pulling everything down and putting it back up again.
The approximate 12" separation is concerning for sure. I like your crossbar plan that provides better separation and growth for a UAT stick. When I think about you being located between those two airports that I can see arenāt very far apart themselves, I fear that your heavy-handed gain of 49.6 may well be overwhelming your receiver with distortion that is limiting your systems ability to gather clean data streams. I would pull that back to a hard-set value of maybe 42 and review how that influences your signal and range values in the 1090 graphs. I think the fence top rail pipe is a good choice because it performs well and is light enough to be more comfortable to work with at height and extended reaches.
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I tried pulling back gain before but that was after having made some other adjustments. 49.6 is a holdover from when I was getting almost nothing but was sure that -10 wasnāt the way to go. Any further reduction in gain was bad for the receiver. But that was before the 9.0.1 install, so Iāll try pulling it back and see what happens.
I believe that gain optimization script that you ran previously is meant only to test and sample gain changes and results for testing purposes only and not a vehicle to reset your gain to a specific value. There is a good script available to install a actual gain adjustment feature to the Piaware SkyAware display window. I installed it with no issue and now use that to easily change my gain from a simple pull down menu in the title bar. I will look for that and let you know if you are interested.
Actually, the reference Iām talking about is from abcd567 listed as post 34 on Nov 8 from this very same topic posting we are on here. He has done us the great service of providing the script on Github.
RG-6 is 75 ohm cable. the ADS-B receivers use a 50ohm antenna system. So, youāll have quite a bit of attention with that CATV cable at 75 ohms. Also, the ADS-B receivers operate up at 1090MHz or 978MHz which is pushing it for a āsmallerā cable. You can Google search coax line loses (or something close) and see just how much loss youāll have with that cable compared to others. When comparing cables, 3db is a reduction of 1/2 of the signal for a given length. Not sure how far you need to run it but the shorter the run with the best cable you can afford will greatly improve your data collection.
It is true that the RG-6 cable referred to early in this post was of the 75 ohm cable tv variety but RG-6 cable does exist in the 50 ohm flavor.
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I noticed a definite reduction in performance over the weekend while it was wet. Iām wondering if thereās some water seeping into the plastic cavity of the antenna that evaporates out when the sun hits it?
As for the cabling mentioned by @estruble, I opted to upgrade to LMR400 (probably actually KMR400, but the seller claims itās LMR 
). This gives me better performance than the LMR240 I hadāeven at a longer distanceāand doesnāt have the impedance of the RG6.
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