I’m currently using a NooElec NESDR Smart v4 SDR with ADS-B Dual 978 MHz + 1090 MHz filter in front of it for 978MHz UAT, fed from a 1/4 wave ground plane via 10ft of FSJ1-50
Does anybody have comparative specs (sensitivity and Noise Figure) for both this NooElec dongle and the FlightAware Pro (orange) ?
I plan to improve my 978 MHz UAT reception and debating what would be the best ‘bang for the buck’ out of:
RF Dongle upgrade
Antenna Upgrade (just about anything would be an improvement !)
LNA
Improved filtering (strong 850MHz cell signals in the area)
Raising the antenna is the most important thing. If you can go above most of the surrounding obstacles the range will improve, even with a simple antenna.
I can’t do much about HAAT for the antenna - it’s in the attic and as high as I can get it, but agreed that higher antenna gain is going to help improve reception
Beyond maximizing antenna performance and minimizing the feeder loss then the sensitivity and noise figure of the SDR Dongle become limiting parameters (interference/filtering aside)
I did find the following data for the FlightAware Pro Stick (orange):
Amplifier : 19dB with 0.4dB noise figure and OIP3 +39dB
So it looks like it has a pretty decent front-end - does anybody have similar data for the NooElec dongle ? - That would help decide if an LNA would make a significant difference to my current setup.
[Edit - I’ve reached out to NooElec support and will share any data I get ]
Getting the antenna outside will be a significant improvement.
There are ways getting around housing regulations.
A quarter wave antenna will easily fit in an unused plastic vent tube.
With a quarter wave you could probably also say it’s a lightning rod if you make it thick enough and run some lighting rod wiring to the ground from the antenna position.
The LNA in the orange prostick isn’t really worth it because it doesn’t have any filtering on the output.
The uputronics box will be a much better upgrade.
You can then experiment with the filter you already have (before the LNA, after the LNA).
If you have it in the attic anyhow, the uputronics box should come before those 10 ft of coax.
Well it depends how good the coax is i suppose.
A 978 antenna, be it the FA 978 antenna or the adsbx antenna (978 + 1090) would also be a good upgrade.
I don’t think the orange stick wouldn’t be much upgrade at all in your situation.
But that’s only my gut and i can’t really back it up.
Not so much am issue of housing restrictions as it is being able to get onto the roof and then finding something to attach to (or hide it in), so probably stuck with indoor for now. My 1090MHz antenna is indoors and same height and getting decent range on that straight into the FA Pro Stick Plus
I received a quick response from NooElec
‘The Noise Figure is 3.5dB when the internal amp of the SDR is set to max gain’
So it has a NF 3dB higher than that of the FA Orange.
Looks like a combo of higher gain antenna such as FA 978 MHz and FA Orange or (better) an LNA with low NF would yield a pretty significant improvement.
BTW - Thanks for your scripts, I’m running your graphs1090 locally and tar1090 on a VPS providing a public view using data pulled from my piAware
It’s $50 but it will actually provide an improvement.
As i said before i wouldn’t be so sure that the FA prostick will be any improvement over the Nooelec sdr.
Interference is really significant. So personally i’d get the filtered LNA instead of a 978 antenna.
Agreed that $ spent on LNA with filtering for my existing SDR, rather than replacing it with an unfiltered unit would be better investment.
Thx for the link - I hadn’t seen a SAW filtered LNA for 978MHz. I did ask NooElec if they had plans to add 978 and 1090MHz versions to their SAWbird product line. The answer was not at this time.
