FlightAware Discussions

Next Antenna... and Coax Decision

Hey everyone,

I’m currently using the Airnav antenna (the one from Amazon with the fixed 10m coax tail)

I’m in the market for upgrading it to one with a connector, so I can use decent cable.
Any thoughts on my top three before purchasing?
My main goal is to increase range, so picking up faint distant signals…

  1. Vinnant COL1090/7.5-P
    COL1090/7.5-P
  2. Jetvision A3
    "A3 ADS-B" Antenna (1090 MHz) + 5dBi stable weatherproof
  3. Pimorni
    ADS-B 1090 MHz Antenna (1.2m, 8.5dBi) – Pimoroni

I’m therefore also after a pre-made 10m (30ft) of the lowest loss coax at 1090Mhz.

:thinking:

Did you check actual vs theoretical range?
GitHub - wiedehopf/tar1090: Provides an improved webinterface for use with ADS-B decoders readsb / dump1090-fa

Also could be that you need a filter more than anything, if you’re going for max performance either the uputronics or rtl-sdr blog filtered LNAs for 1090 are the way to go.

I’ve not checked, other than on Heywhatsthat.

I have several dongles and filters and do indeed use the Uputronics 1090 filtered preamp.
I have a Pro Stick, Pro Stick Plus, RTL-SDR, Nooelec and various 1090 filters and preamps that I’ve been playing around with.

The antenna is located on a pole on my chimney stack, so I can’t get to it easily, so I want a good antenna and coax combo, as it will be up there permanently. I can mess around with various dongles, filters and amps etc in my loft.

Well put the outline into tar1090, try the /tar1090/?pTracks to display track data and you’ll see pretty well how it compares to actual reception.

Brilliant - thank you!

I have one of the Vinnant antennas, but the 5/8 colinear. It’s been up on the roof for 18 months and has performed very well in conjunction with the rtl-sdr.com LNA. I have the LNA mounted in a small waterproof box on the mast fed by a bias-t.

The Jetvision antennas have a good reputation, but are obviously somewhat more expensive. I don’t know anything about the pimoroni antenna.

If you want especially low loss coax, you probably won’t find a pre-made lead, but you can probably get “OK” quality ones. For example the Vinnant guy sells pre-made H155 coax patch leads of the length you want, but that has a loss of 29.6dB/100m at 1GHz. Compared to something like M&P Ultraflex 10, which has a loss at 1GHz of 13.8dB/100m, it’s considerably higher. If you have an LNA mounted before the coax this is not quite so important since the amp will compensate somewhat for the coax loss. If the amp is after the coax, having a low loss feeder will make much more of a difference.

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Many thanks for your input calius - much appreciated!

I am using since about 7 months the Jetvision with an Uptronic filer and a RTL-SDR dongle. I am very please with it.
My reception improved a lot.

I contacted Günther form Jetvision and he was able to make me a nice offer, so perhaps an option…???

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Thank you Dutchyb - I’m torn between the Jetvision and Vinnant.

The Vinnant is bigger / longer, so presumably set for a different wave length, but I’ve no idea which is best for what :thinking:

I am using the Jetvision as well after several attempts with other antennas

Whenever you are getting close to your max theoretical range, it doesn’t matter which antenna you are using.
The A3 is well maintained, it’s outdoor now since mid of last year without any issues or corrosion on the mast holder.

Some add more segments to the antenna, that can improve the range/reception but in most cases it’s only on the paper.
i would not expect a significant difference especially if my previous statement with the max. range is valid.

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Thanks for your input @foxhunter

Yes, I’ve come to realise that the horizon and objects in its way is the limit, rather than better equipment once you’ve reached a certain point in quality components.

I guess I should have said I want to maximise my potential range, rather than increase it.

Yes, I agree that once you’ve gone so far with equipment, its diminishing returns - hence I want to increase my pole mount length and put the best antenna for range I can get, as it’s staying up there.

I’m torn between the Vinnant and Jetvision - the Vinnant states a higher gain at 1090Mhz, but what the actual gain is how much difference it actually makes , I’m not sure.

I just don’t want to go to the effort of installing something and then change my mind, hence decent coax too.

Decisions, decisions :grin:

That’s not how ADS-B works. The distance is (almost) never limited by the “faint signals”, but by the horizon obstructions.
Antenna height, to be above obstacles, is much more important.

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Thanks @SoNic67 - I was coming to that conclusion too, as my most distant aircraft I receive show a good dBFS level.

I’m going to increase my antenna height, as much as possible.

Maybe I should just stick with my Airnav antenna, as I’ve got about 10 feet of cable left on it in the loft, so could raise it higher to use that up so only about 1 foot comes into my loft space.
The coax runs straight into an Uputronics filtered preamp anyhow, so I guess any loss in the cable will be clawed back, to a certain degree.

Cor, you’ve got me thinking more now :laughing:

Maybe a 30 feet run of good quality coax won’t make that much difference for ADS-B reception anyhow :thinking:

The filtered LNA are useful if you have cell towers close-by and when you want to add more cable.
For example, I have a LNA at the antenna and 45 meters (150 ft) of RG6 coax after that.
Also, modern roof shingles attenuates a lot of the 1GHz signal, moving antenna outside can yield better results.

Beside the Antenna it is important to understand which obstacles you have. Some fail due to the high amount of other waves around coming from mobile networks etc.

Depending on that you might need additional filter and/or LNA…
But it’s a kind of try and error.

I did some testing with different sticks, antennas and even with/without filter.
I am obviously in the glad situation that nothing beside the horizon blocks me.
Friend of mine is in the middle of vienna and required LNA and filter

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I’ve found an LNA and filter helps after multiple 24hour A/B live testing with my Airnav.

I think I’ve settled on the Jetvision A3, so do I order their own 10m coax run or is there a better one from another supplier… or does it not really matter given I’ve got pretty good reception; the lowest I ever see at the moment is around -20dBFS?

Serves him right! :sweat_smile:

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@PhilKey
Why not asking Günther form Jetvision, sometimes he has an offer antenna with cable. He made me a great offer

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Good plan @Dutchyb - I’ll pop them a message!

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@PhilKey
Good luck. In my experience he is always willing to help someone

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