Why I can't see all the planes from FlightAware on PiAware Skyview?


#1

On FlightAware, I can see commercial airline planes passing 3000 ft over my house. The thing is I only see 1 out of 5 on Skyview. Any idea why?


#2

Is it possible that the gain is set too high and the receiver is just overloaded?


#3

Do you have MLAT enabled?

Also, remember that not all aircraft are ADS-B compliant.


#4

Is 63983 your site?

That is located in a suburban area, so the signals might drowned out by cell phone towers and/or the reception is limited because the antenna is inside and/or is blocked by other buildings.


#5

Thanks for your answers. I have a Rpi3 so I don’t think I can set the gain.
Problem is that I’m right in the corridor leading to the airport (planes are just 3000 feet over my head) and the antenna is “seeing” them from the window. Also I can sometimes see planes that are 20 miles away but not the Air Canada plane that is right over me…
Thanks for your input because I’m finding this to be frustrating since I can see all the planes on the regular FlightAware but not on the PiAware.


#6

Yes, you can set gain, either by editing piaware-config.txt which you can access when the sd-card ist plugged into a PC or by ssh-ing into it and running rtlsdr-gain 49, I think. There are many threads discussing this on this forum, so just take a look around.


#7

Thanks for the advice. My gain was set to -10 (AGC). Now I’m trying the system with different values but there not seems to be a difference between the different settings. Not sure it is the reason why I don’t see many commercial airline planes. Any idea?


#8

Any chance of putting the antenna outside, just to see whether that improves reception?

Btw, what type of atenna are you using, and what type of dongle?
,
-10 ist the max value for gain, the lowest is 0, 49 the highest you can set, apart from -10. Not sure it it changes anything when you have a dongle without built-in amplifier.


#9

Antenna : 2.5dbi 1090Mhz and it plugs into a Prostick Plus.


#10

hi Yves
i am at St.Laurent, using RPi3, Prostick Plus, DIY spider antenna, 5m sat cable.
3d floor, balkony mounted antenna, 3nm from the airport. gain 42.1 works well for me .
most of the DHC8’s / E170’s are only seen through MLAT (Jazz, Porter etc).
VRS display them all.
HTH
evangel


#11

Thanks for the input.

The problem is still there. I tried different gain settings without results. I still “miss” major airline planes that are flying 3000 ft overhead.
I don’t have a clue on what to try next.
Thanks for your help.


#12

Maybe a FlightAware 1090 MHz bandpass filter would help.


#13

Do you see other MLAT aircraft? In the list on Skyview they are a sort of pale yellow/orange sort of colour.


#14

What rate of messages per second are you seeing reported in Skyview? In an area like Montreal, you should be able to receive hundreds of messages per second with a good site during busy times of the day. If you’re seeing a lot less than that then your site is not well optimized (consider: antenna location/height, antenna type, external filter).

It sounds like you’re using a small indoor antenna? That isn’t going to work well in general. Also as noted by others you may need an external filter to improve reception (even with a Pro Stick Plus in some cases).


#15

Hi Eric,
Looks like an antenna problem from everything I read.
I have between 20 and 23K positions reported on a daily basis. Is that the rate you were asking for?
Also please what type of filter I should buy (on Amazon?).
Thanks again.


#16

Look for the “Messages” rate in the upper right corner of Skyview:
05 PM

That is a proxy for how well your receiver is working.


#17

You can get the FlightAware filter here: https://www.amazon.ca/ADS-B-1090MHz-Band-pass-SMA-Filter/dp/B010GBQXK8/ref=sr_1_2


#18

Is the antenna inside or outside?
If inside, do you have metal roof or possibly metal in the insulation in the attic?


#19

The antenna is inside (window) where it “sees” the planes flying by. From what I know there’s some kind of foil in the walls and ceiling.
Thanks.


#20

Hi Eric,
The highest number I reached is 20/sec.
I ordered a filter. Hope it will help…