Try as I might, I couldn’t get the RTL-SDR.COM dongle to ouput the 5v required to operate the LNA.
If you have written Piaware SD Card image to your microSD card, then here is the solution:
https://www.rtl-sdr.com/getting-the-v3-bias-tee-to-activate-on-piaware-ads-b-images/
2 Likes
Thanks!
I’ll give it a go.
Success!!!
Many, many thanks, abcd567!!!
1 Like
Anyone else getting this error installing the Python Imaging library?
pi@piaware:~$ sudo apt-get install python-imaging
Reading package lists… Done
Building dependency tree
Reading state information… Done
Package python-imaging is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package ‘python-imaging’ has no installation candidate
Thnx,
Scott
Hi Scott
Which OS you are using?
On my RPi with Raspbian Stretch I get perfectly normal response:
pi@raspberrypi:~ $ sudo apt-get install python-imaging
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
libjbig0 liblcms2-2 libtiff5 libwebp6
libwebpdemux2 libwebpmux2 python-pil
Suggested packages:
liblcms2-utils python-pil-doc python-pil-dbgThe following NEW packages will be installed:
libjbig0 liblcms2-2 libtiff5 libwebp6
libwebpdemux2 libwebpmux2 python-imaging
python-pil
0 upgraded, 8 newly installed, 0 to remove and 6 not upgraded.
Need to get 1,119 kB of archives.
After this operation, 2,953 kB of additional disk space will be used.
Do you want to continue? [Y/n]
... ... ... ....
.... .... .... ....
Selecting previously unselected package python-imaging.
Preparing to unpack .../7-python-imaging_4.0.0-4_all.deb ...
Unpacking python-imaging (4.0.0-4) ...
Setting up liblcms2-2:armhf (2.8-4) ...
Setting up libjbig0:armhf (2.1-3.1) ...
Setting up libtiff5:armhf (4.0.8-2+deb9u2) ...Processing triggers for libc-bin (2.24-11+deb9u3) ...
Setting up libwebp6:armhf (0.5.2-1) ...
Setting up libwebpmux2:armhf (0.5.2-1) ...
Setting up libwebpdemux2:armhf (0.5.2-1) ...
Setting up python-pil:armhf (4.0.0-4) ...
Setting up python-imaging (4.0.0-4) ...
Processing triggers for libc-bin (2.24-11+deb9u3) ...
pi@raspberrypi:~ $
Plain old Piaware 3.5.3…
But this is whacky - it just worked now? Not sure what I did or didn’t do. Very odd!
Will continue forward and try it…
May be sudo apt-get update or sudo apt-get upgrade did the magic 
Worked…looking at the scan now.
Thanks for the magic.
Thinking I may need to install that FlightAware filter - running original FA orange dongle.
Edit: Running FA antenna on roof, 30 ft RG6.
Yes, GSM-850 is strong at your location.
Cell/Mobile phone is everywhere now. Filter has become inevitable almost everywhere.
GSM-850 is used in most of North, South and Central America (ITU-Region 2)
GSM-900 / EGSM-900 are used in most parts of the world (ITU-Regions 1 and 3): Africa, Europe, Oceania, Middle East, Asia (apart from Japan and South Korea where GSM has never been introduced).
Pity it doesn’t have a cover, maybe just a bit of heat shrink to keep it protected in the roof space. So will this replace the need for the FA filter? Or have this in line with them both?
Range is determined by the signal to noise ratio. This is the signal you want over the signal you don’t want.
Filters removes both some of the signal you want (called the passband attenuation) and a lot of signals you don’t want (stop band attenuation). For the FA filter the passband attenuation is around 1.6dB to 2.3dB and the stop band attenuation is around 40dB. The cavity filters are usually around 0.5dB passband and 60dB stop band.
You want to have just enough filtering to remove the unwanted signals. Adding more filtering will remove more signal but will also diminish the signal you want and might lower your signal to noise ratio.
So will this replace the need for the FA filter? Or have this in line with them both?
Depending on your location and how strong signal you have will determine how much filtering you need. So try with both filter vs 1 filter and see what works better.
1 Like
I put my filter back on. Running the scan now. Likely will leave it on for a week. Then may run the analysis for gain (again). I see that the scan too says it’s “Tuner gain set to 29.70 dB” so I must have it set to AGC.
Scott
does anybody know if the following configuration is suitable / will work for the bias-t ?
cantenna → coax → FA filter → v3 dongle → RPi
thx / evangel
Yes, the RF Scan sets the gain to 29.7 at start of scan. A gain of 29.7 is used as it is a median value. Too high (49.6 and AGC) or too low (less than say 15) gain during RF scan will not give results which correctly show the interfering signals.
Unfortunately the scan does not set gain back to original value at the end of the scan.
The Gain optimization scripts also leave the gain set to a low value when these complete their cycle.
In both these tests, the user should manually set gain back to the value it had before start of these tests.
By the way, have you seen this thread about mods to include (display + set) gain from SkyView dump1090-fa map / dump1090-mutability map?
Read / Set Gain from SkyView and Gmap
.
Oh snap. I didn’t. Let me get a coffee and set this up.
The idea to include gain setting in SkyView/gmap originally came from @evangelyul. He thought of it, then referred to me for helping him with it. I tried to built on his idea with very limited knowledge of PHP and Bash script. Unexpectedly I succeded.
@evangelyul was actively involved in the entire development process. Please see this thread if you are interested in history of development:
https://discussions.flightaware.com/t/set-gain-from-browser/36278
2 Likes