FlightAware Discussions

NooElec ADS-B 8.5cm Antenna Bundle gain JOKE

I bought this 16.5 cm antenna with 3m cable and SMA as a starter with the FlightAware Pro Plus stick as I wasn´t sure where I´d exactly mount things. (currently right under the roof-top)

NooElec quoting the same 3dBi gain for their dedicated 1090MHz 8.5cm mini antenna I took the plunge, cuz I thought it must be better when I use it same position without a cable / directly on the receiver.

Theory.
Reality: When I get a dozen planes and up to 400km coverage with the prior antenna, I don´t get a single one with the NooElec. <aarrrggghhh>

Please explain! Thanks
G.

NooElec antennas seem to be randomly tuned and generally of very poor quality.
At least that’s what i’ve heard from some people who bought them.

1 Like

(1) TWO RUBBISH ANTENNAS I HAVE TRIED

Rubber-Ducky-R2
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(2) TESTING OF RUBBER DUCKY ANTENNA

(2.1) At 1090 MHz: SWR = 15.13

(2.2) At 1615 MHz: SWR = 2.987

If you have appetite to make a simple DIY antenna which will outperform the mag-mount whip and the NooElec antennas, try this:

QUICK SPIDER - No Soldering, No Connector

Note:
in addition to parts shown in above post you will need an F-female to SMA-male adaptor or pigtail to connect DIY antenna to ProStick

F-femal toSMA-male RG316 Pigtail

SWR of 15 at 1090 MHz? What is that, 24% efficiency or so?

@abcd567 Thanks for your qualified input!

  • Where exactly do I need to attack when I want to disassemble the NooElec 978 mHz part, which I´ll never need?

  • My Yilianduo looks very similar to your quoted coiled whip, but isn´t bad at all. 200 NM under the roof-top!

  • Can one measure more concrete gain numbers without very special gear with SW like CubicSDR or GNU Radio? I got a NESDR Mini 2+. (and an oscilloscope)

  • Need to check more DIY. Got SMA connectors, RG174 and 1mm copper wire.

  • Ordered a AirNav ADS-B 1090MHz 66cm outdoor antenna (seems same as FlightAware, which is currently unavailable), but Amazon is totally mum about delivery date.

Thanks for any (further) advice
G.

Isn’t the tip mounted with a screw on the socket? That’s what normally would be the case. You can remove the tip and replace it with a hard wire in the correct length.
That’s what i did without cutting anything on the original

If you’d searched here (or asked), you could have discovered they weren’t worth buying.

Sorry you got caught, but as they say: “When a deal sounds too good to be true …”

NooElec is all over the place with SDR hardware and quite some brand, so I didn´t expect such a lemon at all. I´m about to try support.
Thanks
G.

Yeah, their SDRs and LNAs seem quite good.
Not sure why they would sell such lousy antennas.

Yeah - that’s fair. I was surprised to see they put their name to something like that.

I did not purchase the NooElec one. Mine was unbranded one from ebay.
I cut the plastic by a small hacksaw. The NooElec one may be open-able by twisting.

 

I have tried 2 similar to yours. See photo below. The left one is 300mm long (including base) and middle one 200mm long (including base) like yours.
Both performed miserably.

I have removed the bases and using the bases for my DIY antennas (Click here).

 

Unfortunately measurement of gain requires sophisticated and very costly equipment like Anechoic Chamber, signal generator, VNA etc.

 

I am using Flightaware 26"/66cm 1090 MHz antenna and am very satisfied with it. Have no experience of AirNav antenna, so cannot tell anything.

The Airnav antenna performs similar to the Flightaware but with the disadvantage of a fixed cable.

Thanks for your detailed reply!
Re NooElec disassembly: Did some twisting and bending. The top will need some (or more <g>) force to come off.

Re coiled whips: So the whips are connected to signal and the base to ground / shield!? No coils or sth. in the base?

Re measurements: Costly, yeah, what I heard in Andreas Spiess’ YouTube videos.

Is it worth it to try some tweaking? Saw some antenna-related settings in the SW, but can´t find them any more.

Re FA vs. AirNav: Planning to stick the AirNav onto some tube to raise it above the roof-top. (ca. 50 cm)
How much above the roof should the antenna-base be and does the tube material matter?

And: Would you shorten cables? Need a meter or two (depending on model and mounting).
The coiled whip has 3m, the AirNav seemingly 10m.

Thanks again for your help
G.

@gue22 - Definitely worth tweaking. There are some threads around here about those coiled wire antennas. People shorten them up to a specific length and stick the magnet mount on round metal lids to cookie tins or similar. The metal lid gives the antenna a ground plane and shortening up brings it better in tune for 1090. Not sure what to search for but you can optimize those wire coil antennas. When properly tuned, an antenna can help pull in signals of interest while “rejecting” noise.

Lots upgrade to different antennas like a discone or the FLightAware stick. I use the 26” FlightAware stick and it made a huge difference to my range and numbers of aircraft tracked. It was just a connect up and go kind of thing but i did need to also get coax and a proper adapter connector.

If mounting antennas outside, you may also want to look into lightning protection.

Those antenna settings you found - maybe to enable LNA power on the antenna cable? I think the Nooelec’s have that capability.

On shortening cables, it depends. There is per-foot/meter loss in coax and you can improve signal strength, but if the cable isn’t too much longer than needed, it gives you flexibility while sorting out your station. Hand wavy but hard to answer without knowing your coax and the length you are planning to cut.

Regarding the FlightAware vs AirNav antenna… I have both. It seems like the AirNav one are getting me more planes. Note: They are still indoor, placed 20 cm apart, and a lot of trees, buildings, etc. are in the way at the moment. The setup is the same for both. Antenna > Uputronics LNA > AirNav green stick > Pi 4B.
The persistence mode was enabled at the same time this morning to see the difference.

AirNav/RadarBox. Max range is ~155 nm

FlightAware. Max range is ~100 nm

No coils inside base. Only lower part of threaded
brass stud, to which core of coax is soldered
Please see details of base here.

Thanks for the schematic! This simplicity opens up a lot of options. Got the Mag Mount thread already open, but didn´t get around to it.

Possibly stupid q: If I don´t use the base I´d use a ground plane or where do I hook the shield?
I think I remember some VERBALLY grounded radio with a flat antenna (300 Ohms?) cable from my youth (for AM radio?). <grin>
Nothing else than the mains ground??

You´re also confusing me with your Quick Spider article. The RG6 apparently is 75 Ohms and not 50, like the RG174.

And is there a reason that the stuck-in radial part is 21 mm?

Lotsa q!
G.

Guess 150 NM and all kinds of obstacles is some accomplishment in Denmark. What´s your elevation?

I remember my flight instructor wanting me to find the highest “mountain” in Florida, called Mount Trashmore, a cultivated ex-dump, 150 feet “HIGH”. <rofl>

I´m on 300 m with unobstructed view of Alps peaks. :wink:

Cheers
G.