3 antennas tested and found something in the garbage

FlightAware ADS-B Flight Tracking
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I had a blue nooelec with the stock antenna and a raspberry pi in my attic for a while, this is a plot of a few hours-

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I had some time off from work and wanted to see if I could do better. So I bought a FlightAware Pro Stick and a FlightAware filter and made this setup-

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And it worked like crap. It took all day to make this plot-

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So I tried making a coco antenna with 4 segments and that worked worse of all. Then I cut the 2 zip ties that held the filter and Pro Stick and let them hang down so the pigtail was straight instead of having the loop in it. That made a huge difference. Here’s a plot from just a few hours. I made it to North Carolina :slight_smile:

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Ultimately I want to move whatever I find works best to the roof or maybe even on top of one of these very tall pine trees in my yard.

After the last few days I have a lot of questions.

  1. Has anyone put one in a tree? I guess I have to consider mounting and heat and powering it. It will downlink via wifi. I’m either going to power it with solar and batteries or run a wire up there and have a 5 volt switching power supply and run it on 12 volts . I’m seeing about 4 watts total power consumption on average right now.

  2. Does anyone have any tips for optimizing the FlightAware Pro Stick, FlightAware filter and spider antenna that I made?

3 And lastly, my friend found this on the curb and gave it to me. He brinmgs me old computers and whatnot and I give him all the scrap metal from my many projects (like the gas turbine in the minivan project). Can I use this to help figure out my antenna performance?

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Thanks for your time.

Chris “turbochris” Krug

If you want to see my other projects here’s my youtube channel.

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[quote=“turbochris”]

After the last few days I have a lot of questions.

  1. Has anyone put one in a tree? I guess I have to consider mounting and heat and powering it. It will downlink via wifi. I’m either going to power it with solar and batteries or run a wire up there and have a 5 volt switching power supply and run it on 12 volts . I’m seeing about 4 watts total power consumption on average right now.

  2. Does anyone have any tips for optimizing the FlightAware Pro Stick, FlightAware filter and spider antenna that I made?

3 And lastly, my friend found this on the curb and gave it to me. He brinmgs me old computers and whatnot and I give him all the scrap metal from my many projects (like the gas turbine in the minivan project). Can I use this to help figure out my antenna performance?

800×600 83.3 KB

Thanks for your time.

Chris “turbochris” Krug

If you want to see my other projects here’s my youtube channel.

Your 8591A is an old gem – manuals for it are available on the Net. Run it through its self-cal after half an hour or more warming up. Send questions along my way if you like. I have one of its litter-mates, the 8594E, which goes up to 3 GHz and has some more bells and whistles.

If you insist on running your Pi over WiFI, you will personally experience the First and Second of Buddhism’s Four Noble Truths –

The First Noble Truth is that the World is Full of Suffering. That’s what attempting reliable, long-term stable WiFi is on a Pi.

The Second Noble Truth is that Suffering has a Cause. In this instance it’s the desire to use WiFi on a Pi for a system that wants constant reliable communications.Remember, desire is the root of all suffering. Particularly the desire to use WiFi on a Pi.

Now I’m not saying it’s impossible to do. I’m just suggesting there are easier and less stressful ways to get the job done.

If you’re merely interested in ADS-B and not pursuing a Path to Enlightenment, it would be far easier to run the whole thing on wired Ethernet plus POE. Another recent thread had a pointer to a POE receiver module made for devices such as the Raspberry Pi – Ethernet plus 802.3af POE in, and Ethernet plus 5V out for around ten dollars U.S.

Experiment, keep good records, let us know what works and what doesn’t, and have fun!

bob k6rtm
(Clear Seeing, Calm Abiding)[/quote]

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Thanks for your reply.

I’ve been through some raspberry pi nightmares. I started using these and they went away. I have the latest piaware loaded on a model B2 with one and it’s been rock solid.

adafruit.com/products/1030

The reason I don’t want to go ethernet is the neighborhood I live in loses a lot of electronics each year due to lightning. It has something to do with the soil being a bad conductor or something like that. I don’t mind loosing the piaware setup but if it hoses my switch and anything else it would hurt.

I’ve been reading and I think I need to come up with a static source that transmits on 1090 to use this spectrum analyzer.

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There are a few posts around for using local oscillator leakage form a CHEAP sdr (not the FlightAware SDR Plus, which has a good preamp) as a cheap signal generator.

You can try this experiment – connect the input of a cheap SDR to the input of your spectrum analyzer. If you have local oscillator leakage, you should see a strong spike near the frequency the SDR its tuned to. Or at least a strong spike somewhere on the spectrum analyzer. Using whatever software you like to tune the SDR, find a frequency that results in a spike at 1090. That may be a harmonic, a multiple of some lower frequency that shows up around 1090.

There are also cheepie tunable signal generators on eBay that can cover 1090.

And as you learn more about spectrum analyzers, some have a built-in tracking generator (such as my 8594E), which puts out a signal that tracks the spectrum analyzer input. Yours has a plastic plug marked RF OUT where the TG output would be.

Lightning can indeed bee an issue. A ham group I worked with in the past had a cabinet full of repeater electronics up on a mountain more or less vaporized. Very impressive, and not a lot you can do about it.

cheers

bob k6rtm

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DVB-T RTL 820 as 1090 Mhz Signal Generator

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  1. Can you give us dimensions on the antenna element lengths?
  2. WiFi works nicely if you really have to, but it’s a nightmare compared to Ethernet. If you really must, get an external wifi adapter for $3 with antenna connector, and a directional Yahi for $10, point Yagi at router to get best signal strength.
    Pi’s onboard WiFi Adapter is not strong engouh to cover a larger distance, a directional antenna and an external adapter will also remove a source of interference in close proximity to a sensitive dongle.