This photo is where I got the idea for a cantenna.
I found the easy spider performed slightly better than the cantenna.
A quick question on the noise in the graphs (adsb-receiver project), is a noise of -30 better than a number closer to zero i.e. -20?
Noise:
-30 dbfs is less noise than -20 dbfs
-30 is better than -20
Thanks @abcd567 
Iâve tried out different Spider and Collinear. All nearly with the same result.
Then I decided to buy the Jetvsion.
Placed on top of my SAT dish (836 ft above msn)
PRO+ Dongle
Seeing 130 planes out to ~200nm
Happy!!
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Glad you are having success. I wasnât familiar with the Jetvision company so I looked at their website. The technical specs for the antenna I think you have says that it is a 3 element 1/2 wave collinear design.
I will have to try to make one to see if it works in my location.
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SR-71 Blackbird would do 120,000 (flight level 1200?)
Bob
SR-71 doesnât fly anymore. Plus I donât think it got too much above 85,000 ft.
https://www.sr-71.org/blackbird/sr-71/
Project Loom balloons can get that high. Speed is the give-away.
I said âwouldâ not âdoesâ.
The web site says â81,000+â.
I have first person knowledge of 120,000.
The only time an SR-71 was that slow was parked, on takeoff, and taxying. 
So thanks for âcorrectingâ me.
Bob
Youâre welcome.
PS: When we speak, we use context.
When someone asks âwhatâs that?â, and someone says âx would be capable of thatâ automatically implies that he is answering the question.
Not that he gives a totally unrelated piece of information (even if might true by itself, but not verifiable without a secret clearance).
âImplicationâ is like âassumeâ especially if using the written word instead of the spoken word.
I too was watching those objects tracking slowly through South Eastern Ontario and Northern NY which is the first I saw them. By that time FA had a designation that was a clue that it was a balloon but still have no clue as to what research they are doing.
Drones have replaced all maned reconnaissance missions though I have no first hand knowledge of this. Interestingly enough there is a military/research area on the Southern shore on Lake Ontario for drone flights. I also think Calspan at the Niagara Falls AFB is doing drone research. The last known flight was in 1999 and Iâm sure optics and drones surpassed it for intelligence gathering.
I also have no understanding why specifications of the SR-71 are classified. Every country we ever overflew knows the operational envelope of the plane but maybe not the edges of that envelope.
I know if no other âaircraftâ capable of FL 80 so if someone asks what would that object be all info is relevant for objects that could get that high. Obviously the airspeed would make it impossible for a SR-71. However a military drone might have loiter capability in that speed and altitude. Just a thought.
Nice chatting with you.
Bob