SDR Sticks reception comparison (Nooelec NESDR SMArt, Flightaware dongles)

polkaroo

Member
Joined
Apr 14, 2002
Messages
310
Amazon sent me the wrong stick so I did a simple test with FMP24 before I sent it back. Hope this can help someone else trying to figure out what cheap stick to buy.

Nooelec NESDR SMArt
FlightAware Pro Stick (Orange)
FlightAware Pro Stick Plus (blue)

Same antenna, same gain on each set on P25 control channels at 410 and 770MHz. PPM at 0 and left FMP24 to correct. Shows the difference the amplifier makes in the FlightAware Orange stick makes with SNR and the noise floor.



UHF 7/800:

FlightAware Pro Stick (Orange)89249
FlightAware Pro Stick Plus (Blue)
89250
Nooelec NESDR SMArt
89251
UHF 410MHz:

FlightAware Pro Stick (Orange)
89253
FlightAware Pro Stick Plus (Blue)
89254
Nooelec NESDR SMArt
89255
 

slicerwizard

Member
Joined
Sep 19, 2002
Messages
6,582
Location
Toronto, Ontario
Far too much gain being used with the orange stick. Signal is being compressed into the noise.

And yes, Amazon's Mississauga warehouse can't figure out the difference between the orange and blue sticks. Purchase orange, receive blue. Every. Single. Time.
 

ka3jjz

Wiki Admin Emeritus
Joined
Jul 22, 2002
Messages
22,998
Location
Bowie, Md.
Wait a minute -how is this even a fair comparison? Comparing a SDR with likely a limited application vs. one that's broadbanded.? And the blue supposedly has a bandpass filter, whereas the Nooelec doesn't appear to have one.

This comparison is makes no sense whatsoever..

Mike
 

GTR8000

NYS Database Guy
Database Admin
Joined
Oct 4, 2007
Messages
9,014
Location
BEE00
Wait a minute -how is this even a fair comparison? Comparing a SDR with likely a limited application vs. one that's broadbanded.? And the blue supposedly has a bandpass filter, whereas the Nooelec doesn't appear to have one.

This comparison is makes no sense whatsoever..

Mike
The FlightAware Pro Stick (orange) uses the exact same R820T2 tuner and 0.5 ppm TCXO as the NooElec NESDR SMArt, while also featuring an integrated LNA. Both dongles cover the same 25 MHz - 1750 MHz, so I'm not sure what you mean by "limited application vs broadbanded". It's perfectly fair to compare those two dongles, and to highlight the difference the LNA makes.

The FlightAware Pro Stick Plus (blue) does have a 1090 MHz bandpass filter, so that's not a great comparison to include, although it is interesting to see just how much signal in the 400 and 700 bands it does let pass despite the -30 dB filter.
 

boatbod

Member
Joined
Mar 3, 2007
Messages
2,321
Location
Talbot Co, MD
The FlightAware Pro Stick (orange) uses the exact same R820T2 tuner and 0.5 ppm TCXO as the NooElec NESDR SMArt, while also featuring an integrated LNA. Both dongles cover the same 25 MHz - 1750 MHz, so I'm not sure what you mean by "limited application vs broadbanded". It's perfectly fair to compare those two dongles, and to highlight the difference the LNA makes.
Clearly the LNA is doing something including really raising the noise floor. Did you try tweaking the LNA gain to find the sweet spot for best SNR?
 

ka3jjz

Wiki Admin Emeritus
Joined
Jul 22, 2002
Messages
22,998
Location
Bowie, Md.
And therein lies one of the differences between the Nooelec and the Flightaware SDRs. The Flightaware as a 'Flightaware amplifier' that the Nooelec doesn't. The Flightaware SDRs are really a limited application device since that's the service they're supposedly set for. Yes, the basics are the same but there are some differences, too.
 

Ubbe

Member
Joined
Sep 8, 2006
Messages
4,871
Location
Stockholm, Sweden
You really need to increase the gain with all three sticks and see at which level they begin to get artifacts and intermod. One stick could have lower gain but much better intermod rejection that makes it receive more than the other sticks if the gain where increased. You can't just set one gain level and asume all chips and RF front ends are created and designed equal. In that case the gain could have been set to a fixed value for each brand of stick, but that is not possible to do and we need adjustable gain to fit one particular sample of each stick receiver.

/Ubbe
 

JimD56

KO9JAD/Fire Lieutenant/Paramedic
Feed Provider
Joined
Nov 18, 2004
Messages
209
Location
Davie, FL (Miami/Fort Lauderdale Metro)
I had a NOOELEC and it was not any good, I returned it to Amazon. I went with RTL-SDR Ver 3 and works great.
I run two. 1 for ADSB and one for VHF Air, Mil Air/UHF Analog.
 

GTR8000

NYS Database Guy
Database Admin
Joined
Oct 4, 2007
Messages
9,014
Location
BEE00
And therein lies one of the differences between the Nooelec and the Flightaware SDRs. The Flightaware as a 'Flightaware amplifier' that the Nooelec doesn't. The Flightaware SDRs are really a limited application device since that's the service they're supposedly set for. Yes, the basics are the same but there are some differences, too.
You're getting hung up on the fact that the orange dongle is marketed by FlightAware as an ADS-B stick. The fact is that it's identical to the NooElec, RTL-SDR.com, etc. dongles, and the only significant difference is the addition of an integrated LNA. That's it, everything else functions the same. I don't know why you are referring to it as a "Flightaware amplifier" as if it's some sort of special thing, as the LNA functions across the entire spectrum the dongle can receive; it's not limited to 1090 MHz, if that's what you're implying.

I own three of those orange FA dongles (along with two each of the NooElec and RTL-SDR.com) and they have never tuned to 1090 MHz for ADS-B decoding; I use them with SDRTrunk to decode UHF and 700/800 trunked systems, and they work great. I keep the gain relatively low, but the LNA helps to overcome some of the loss of the passive multicoupler I'm using.
 

slicerwizard

Member
Joined
Sep 19, 2002
Messages
6,582
Location
Toronto, Ontario
The Flightaware SDRs are really a limited application device since that's the service they're supposedly set for.
Absolute rubbish. The FlightAware oranges are extra-sensitive 400 MHz to 1+ GHz receivers that are suitable for all typical analog/digital RX roles.

The oranges work below 400 MHz as well, but their RF gain tends to be similar to other dongles, so something like an Airspy or SDRPlay would be a superior choice there.

Their only "fault" is overloading when very close to strong transmitters. However, even in urban environments, I rarely see this happen.

I suspect they they would really shine out in the boonies where one can find a very low noise floor, hence able to crank up the RF gain, although one typically isn't hunting 400+ MHz signals from the middle of nowhere...
 

Ubbe

Member
Joined
Sep 8, 2006
Messages
4,871
Location
Stockholm, Sweden
It's the dynamic range that is limited in USB stick receivers. You have to increase the gain as much as possible without getting into overload and intermod to be able to get a good sensitivity. The max gain setting are dependent of the local enviroments RF situation. SDRPlay has some band filters that will help a little to get rid of high level signals in other bands than the one the dongle is using, that might make it possible to increase the gain more than in a standard $20 RTL-SDR type of dongle.

/Ubbe
 
Top