FlightAware Discussions

RE: [ Beginner ] - Please advise on dongle to receive both 1090Mhz and 978Mhz

Just dropped it from 40.2 to 32.8 to see how that looks.

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my Chicagoland 978 ONLY site - not much traffic on less than VFR & low winds John Wrycza ADS-B Feeder Statistics - FlightAware

The gain my my uat is set to max. I would like to change it but I can not find out what the range of the gain is. CAn someone tell me the range of the gain values?


I have another question. I would like to look back at the history of the airplane and tracks that my station picks up. Is there a way to do that?

You can’t look at your own history easily. Some of the other feeders do have nice 3rd range graphs.

These are the gain settings for an rtl-sdr device
Supported gain values (29): 0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6

If you have the Flightaware SD card image you can change it this way
sudo piaware-config uat-sdr-gain 44.5

Otherwise edit /etc/default/dump978-fa
and add
DECODER_OPTIONS="–sdr-gain arg"
change arg to the gain value you desire.

You can look at your stats with @wiedehopf 's graphs.
They can be installed using the command below.
sudo bash -c “$(curl -L -o - https://github.com/wiedehopf/graphs1090/raw/master/install.sh)”

Even on a crappy cold day in NYC, I still get a bit of UAT traffic. It goes down to zero when it snows.

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Thanks. I was able to change the gain to 40. I had to do in the dump978-fa file in the decoder line. It took “uat-sdr-gain 40”. I just made the change. I also moved the antenna outside today so it is now outside and about 6 feet higher than before. I am eager to see what effect this has on coverage.

I appreciate all the help you folks have given me.

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Is there any interest in starting a thread about 978 Mhz reception in the greater NYC area? I reside 2.5 nm North of KTEB directly underneath the localizer for the ILS runway 19 at KTEB. There does not appear to be many 978 feeds in northern NJ which makes it difficult to do comparisons. Can we share out experiences? Regards, Richard

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I am close to the Verrazanno, on the eastern side of the Hudson. I am really low, only 40ft AMSL but manage to get 50 or so aircraft per day, when the weather is not too bad.

I have an old rtl-sdr v1 with bias-t enabled (Amp and cavity filter are on the mast on the chimney) with a dpd antenna. I have an rtl-sdr v3 due tomorrow to upgrade it.
I also have a directional antenna with amp and cavity filter in the attic. I have a radarbox 978mhz sdr coming tomorrow to to upgrade it.

I messed up dump978-fa last night an got it working again after lunch today.

My main UAT978 feeder wasn’t setup until recently. dump1090 kept taking over the uat978 dongle. I have removed dump1090 so this won’t happen again.

I’m a few miles away from KCDW.

FA antenna in the attic, FA filter, FA Pro Stick.

Just lowered my UAT gain yesterday morning 40.2 to 32.8 . Too soon to tell if it helped.

My 1090 and 978 antennas have the same horizon view from the roof. If I compare the two looking at planes at similar altitudes the maximum range is basically the same for each. But there are far fewer 978 aircraft visible—on a good day I’ll see 100 on 978 and 4,000 on 1090.
Takeaway: The two systems give equal performance to line-of-sight distances.

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Three “real” aircraft setoff TIS-B/ADS-R broadcasts for 70 aircraft

Thanks for the feedback, I swapped the light blue Flightaware filter from the 1090 Airspy Mini dongle to the 978 dongle and reception improved especially with regard to 978 TIS-B targets. I run 2 feeds, one in front of the house facing SSW towards KTEB, KEWR and other in the back facing NNE toward the Alpine Tower. I ordered 2 more Flightaware filters. The house is brick with plaster walls so all indoor RF propagation is problematic.

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