An ADS-B Antenna Built From Actual Garbage

With the advent of low-cost software defined radio (SDR), anyone who’s interested can surf the airwaves from the FM band all the way up to the gigahertz frequencies used by geosynchronous satellites for about $20 USD. It’s difficult to overstate the impact this has had on the world of radio hacking. It used to be only the Wizened Ham Graybeards could command the airwaves from the front panels of their $1K+ radios, but now even those who identify as software hackers can get their foot in the door for a little more than the cost of a pizza.

But as many new SDR explorers find out, having a receiver is only half the battle: you need an antenna as well. A length of wire stuck in the antenna jack of your SDR will let you pick up some low hanging fruit, but if you’re looking to extend your range or get into the higher frequencies, your antenna needs to be carefully designed and constructed. But as [Akos Czermann] shows on his blog, that doesn’t mean it has to be expensive. He shows how you can construct a very capable ADS-B antenna out of little more than an empty soda can and a bit of wire.

He makes it clear that the idea of using an old soda can as an antenna is not new, another radio hacker who goes by the handle [abcd567] popularized their own version of the “cantenna” some time ago. But [Akos] has made some tweaks to the design to drive the bar even lower, which he has dubbed the “coketenna”.

The primary advantages of his design is that you no longer need to solder anything or even use any special connectors. In fact, you can assemble this antenna with nothing more than a pocket knife.

You start by cutting the can down to around 68 mm in length, and cutting an “X” into the bottom. Then strip a piece of coax, and push it through the X. The plastic-coated center conductor of the coax should emerge through the bottom of the can, while the braided copper insulation will bunch up on the other side. If you want to make it really fancy, [Akos] suggests cutting a plastic drink bottle in half and using that as a cover to keep water out of the “coketenna”.

How well does it work? He reports performance being very similar to his commercial ADS-B antenna which set him back $45 USD. Not bad for some parts of out the trash.

We’ve covered the math of creating an ADS-B antenna in the past if you’d like to know more about the science of how it all works. But if you just want an easy way of picking up some signals, this “coketenna” and an RTL-SDR dongle will get you started in no time.

31 thoughts on “An ADS-B Antenna Built From Actual Garbage

  1. Every half wave omni preforms equally well. at 1095MHZ, element length is two and a half times less critical than building a WiFi antenna. If you want to excel in plane spotting, you either build an co-linear or even a rotating Yagi for that spy headquarters look of your residence.

  2. I wasn’t finished: Also adding a 25-40$ LNA in the antenna base reduces noise further and improves your range. I’ve tried ADS-B reception with just a directional circular polarized patch antenna made for 1542MHZ sat reception pointing straight up. It also preformed as good as any commercial ADS-B antenna, around 500kM range.

    1. It’s soda or pop or sodapop. Depending on what part of the US you are from, just to be nonpartisan. Then there is beer, those new longneck bottles made from aluminum. Cut bottom off use cap without seal.

      1. Except in parts of the South, where the generic term for pop is “coke”. If you want actual Coke you ask for “Co-cola”
        Or, parts of NC where they actually say “soft drink” in conversation.

  3. Junk, nothing but junk—and ugly too. If you want a genuinely wide-band antenna for the higher frequencies, get or build a discone antenna. It’s ideal for listening to a wide range of frequencies.

    “Omnidirectional, vertically polarized and with gain similar to a dipole, it is exceptionally wideband, offering a frequency range ratio of up to approximately 10:1. The radiation pattern in the horizontal plane is quite narrow, making its sensitivity highest in the direction of the horizon and rather less for signals coming from relatively close by.”

    https://en.wikipedia.org/wiki/Discone_antenna

    1. Sure, but this one is specifically for ADS-B. It’s a very old design for a dipole, implemented in a novel way, in the spirit of ham field day beer can antennas (back when they were steel and could be soldered).
      Why is it that people are so quick to say “not a hack” and then criticize a true hack for not being the best solution?

    2. How is a disccone vertically polarized when it’s a horizontal disc? Unless you have one of those with a vertical element, but that’s more a dual antenna isn’t it?
      I noticed the antennas on planes are all vertical BTW, or rather, vertical but at a slant.

      Oh and ADB-S enthusiasts don’t want wideband, they even buy filters to block all but the narrow ADB-s range, and install expensive crystals to not drift. (seems odd now I think about it since planes are moving and in various cloud layers so there should be some drift from that alone right?)

      1. The disc and the cone are ground planes or centerpoise’s I’m thinking. The center element is a vertical polarized monopole I think is the term. There are variations however where one may be I think called a driven element versus a director or reflector element.

  4. “Garbage” refers to organic waste (every tried putting a soda can into your sink’s garbage disposer?). I think you mean “trash”.

    But, who knows? Maybe you can construct a working antenna from rotten tomatoes.

  5. Sometimes trash us better thsn commercial products.
    ….

    After trying two different (expensive) DVB-T antennas that weren’t getting many channels I ended up bendkng a coathanger as an antenna…

    That got me 40 extra channels. Worked ever sinxe. Although i had to use a dremel tp grind the rust off after 6 years use :)

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