Building a Filtered Amplified Coketenna for ADS-B

Combine a proven, easy-to-do concept, the Coketenna discussed earlier, with the best performance RTL-SDR dongle for ADS-B and a filtered low-noise amplifier for great and affordable receive performance.



Receiving element: made from coax center conductor, 68.8 mm in length.
Body: standard soda / fizzy drinks / beer drinks can be used, height 68.8 mm.
Low Noise Filtered ADS-B 1090 MHz premplifier: rtl-sdr.com's new arrival fits inside the can perfectly.
Receiver: rtl-sdr.com v3, or Nooelec SMarTee, or AirSpy/SDRPlay, must have bias-T to power LNA.
Connection to host computer: USB extension cables for $1 each, tried up to 4.5 meters and worked.
Optional: snap-on ferrites for $.30 each to minimise noise pickup by USB cable.

Performance


Same v.3 receivers, 2m coax vs 1.5 m USB extension lead, Uputronics 1090 MHz filtered preamp on a pro Jetvision antenna. Antennas side-by-side on my windowsill, and please no, don't enlighten me why this setup is flawed, I'm not happy either, but I gotta cook with what I got.
Unsurprisingly, pro setup outperformed the Filtered Amplified Coketenna, $50 David vs $160 Goliath, so larger numbers refer to the pro setup.
Total Position reports: 76,905 vs 55,040, 39.72 % more.
Geographical Coverage:



Max ranges: 182.60 nm vs 172.46 nm, and 168.91 nm vs 158.85 nm on Day Two of testing

Build notes and imges


Receiving element from coax center, measure depth of hole of SMA connector, then fold wire in half, secure with washers supplied (sorry for blurry image):



Thicker coax centers e.g. RG6 can be filed down to fit SMA hole, folding a thinner wire e.g. from RG59 coax is more secure.
Make sure measurements are exact, metal part of a V3 is 69.23 mm if you got no digital caliper:



Top hole: Drill diameter or tool usage doesn't matter, as long as SMA connector fits through, 9mm drill does the job, move it in a circular motion to enlarge the hole piecemeal.
Receiver: V3 with same stable Filtered LNA will stick out of antenna body.
FlightAware Pro Stick Plus is half the price of the above combo, performance will be less, but will fit Coketenna body:



Weatherproofing: Plastic bottle on top with cap on:



Survived rain, snow, hail, sunshine, Beast from the East with a plastic bag on top, since seen that concept works next step will be oil cooling in an unattended setup.



Improvements

Cost: Pro Stick Plus would be half the total price.
Longer coax runs: Filtered Preamp could be used on its own, as I only need a short length and really against coax for 1090 MHz I'll leave solving this question to rest of humanity.
Plastic cover: go shopping for a proper length plastic bottle, bin liners do look ugly.
Camouflage: black tape or spray paint does wonders with the neighbors.
Antenna body: aluminum bottles from outdoor shops are close in diameter to a drinks can, but require power tools for cutting.
Cooling: primarily for reliability, as condensation is a worry on the long run, watch this space.

Worth it?


$30-ish in total material cost with a FlightAware Pro Stick Plus, or around $50 with rtl-sdr.com products for equipment. Plus one hour of your time.
Pro level gear is better, but money is money, and ADS-B signal reception primarily depends on antenna location and placement due to line of sight. That means high up, often on the roof, and leaving $50 exposed to the elements in an ideal location will be easier to digest should the worst happen.

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