978 UAT - Is It Worth Adding?

I just tried both of the ones that came with the stratux kit on a VNA, which I believe are identical to your second link, and found that it shows an SWR of about 2 at 1090 and 978 as well. The frequency seems centered between them and they just sticker them differently, since their performance was identical… The top one you linked is clearly too long to be correct for the given frequencies unless they’re using some 5/8 wave voodoo and, even then, the cantenna is better than either of them because of it’s inherent noise rejection and good SWR.

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I have both 978 and 1090 on the same Pi and Monday FA started showing statistics for both.

https://flightaware.com/adsb/stats/user/zeek70706#stats-18102

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What’s your setup? Are you using two different receivers or are you splitting time between frequencies on an SDR or what?
I need to add UAT to my stations asap but haven’t found a simple way, yet, to get dump978 and dump1090 working.

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I use the RTL-SDR V3 with the FA 1090 Antenna for ADS-B 1090 and the Flight Aware Pro Stick (Orange) with the FA 978 Antenna; both connected to one Pi.

Not a lot of flights but the weather hasn’t cooperated either (Snow and Rain lately).

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But you’re seeing some, so that’s great!
What did you have to tweak with the image? Does buster just do this natively now?

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Piaware SD card image 3.8.0 (Buster) by default behaves as 1090 mhz only, though it has 978 mhz builtin, but 978mhz is inactive by default.

If you want to run 978mhz also, you will need 2nd dongle+antenna set to plug into RPi for 978mhz, serialize the two dongles, and issue few commands to activate 978mhz.

Howto : Piaware SD card image 3.8.0 Quickstart Guide

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abcd567 has got you covered for the setup.

Last few days have looked like this (I flashed a new card with the piaware image, so the data is only since Tuesday on these graphs). And antennas are indoors so I would expect much better if/when I put them outside.

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Yep. I have a pair of 978 and 1090 filtered/amplified receiver dongles from another project. That was exactly the plan. Thanks for the link, I couldn’t find it with a search.

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Max 3 UAT planes/day at Toronto
Today only 1 :angry:

https://flightaware.com/adsb/stats/user/abcd567#stats-76000

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In Canada, that’s hardly surprising. Canada doesn’t recognize UAT as a valid ADS-B solution. UAT is really only going to be populated near municipal airports in the US.

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According to the FAA, in the US, about 30% of ADS-B OUT equipped GA aircraft use UAT. FlightAware is missing a lot of VFR flights since most receivers are 1090ES only.

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When the sun comes out (not very often these days), so do the GA-UAT aircraft. I like having a UAT receiver since a lot of them fly almost directly over me and now I can know who they are…

chrome_BOLyPEmEDt

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While more 978 receivers can only be a good thing, you do need to be careful that “30% of equipped GA aircraft” does not mean “30% of equipped GA aircraft in the air”.

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I should have clarified. 30% of piston powered GA aircraft are equipped with UAT. I suspect that this is also a close approximation of how many VFR flights are being conducted with UAT ADS-B OUT. It’s frustrating that FlightAware is missing out on this much VFR traffic. It would be nice if the default piAware receiver configurations were dual frequency.

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Unfortunately that would require two dongles and the user would need to serialize the dongles to identify 978 vs 1090; that’s not great as a default config. You can definitely set it up via just config changes + serialization if you do have two dongles.

It’s not technically feasible to receive both 978 and 1090 at the same time on a single rtlsdr dongle.

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It is very easy and simple to change configuration from default (1090 only) to dual (1090 + 978), but as @obj has already pointed out, it requires two dongles (one for 1090 other for 978)

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How about non PiAware SD card image setups? I tried to run those command to add my 2nd dongle for UAT and it was returned an error “option only supported on PiAware SD card images”.

Appreciate your time.

Trevor

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For Piaware+dump1090-fa package install on Raspbian OS, you have to first install dump978-fa and after that configure. See below:

(1) Install dump978-fa

wget https://flightaware.com/adsb/piaware/files/packages/pool/piaware/p/piaware-support/piaware-repository_4.0_all.deb

sudo dpkg -i piaware-repository_4.0_all.deb

sudo apt-get update

sudo apt-get install dump978-fa

(2) Configure

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2020: My site would see above 4500 aircraft on 1090 and around 50 on 978 on a good day.

2022: The 1090 stats are about the same, but the 978 count now is up to 150 some VFR days.

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Above is out-dated (valid before ver 6.1). From ver 6.1 onwards, use this:

(3.3.4.2) - Configure dump1090-fa & dump978-fa to use dongles of assigned serial numbers

sudo piaware-config uat-receiver-type sdr

sudo sed -i 's/^RECEIVER_SERIAL=.*/RECEIVER_SERIAL=00001090/' /etc/default/dump1090-fa  

sudo sed -i 's/driver=rtlsdr[^ ]* /driver=rtlsdr,serial=00000978 /' /etc/default/dump978-fa  

# Reboot Pi to implement configuration settings 

sudo reboot