Hi there, i recently moved into a place with roof terrace, and was looking forward to excellent ADS-B reception. I started test-installing my antenna to see how good it is. So far, i’m very underwhelmed.
I’m in São Paulo, Brasil.
I’m quite close to Congonhas airport (< 2 miles).
I’m very close to the flightpath of incoming airplanes (~0.5 miles?).
I’m also close to two (i think) cell sites, both on top of neighboring buildings.
My antenna is LOS to incoming aircraft, but my Pro Stick Plus does not pick up their messages. It does pick up some messages from aircraft further away (5 to about max 100 miles), although reception is spotty at best (i get like 10 messages/s on a good day)
Now i don’t know much about antennas, signals, frequencies (much of what i read here sounds like gibberish to me hahah), i’m quite the noob. Is there anything i’m doing wrong? I’ve read that cell towers might interfere with reception, and i have two close by. Can i do anything about that? I’ve read about band filters? Can this help? Is there anything else i’m missing?
The antenna isn’t mounted very well, it’s too close to the metal grid.
If that is mounted with tape … that is prone to fall down at some point.
At the very least use tape at the top and the bottom of the antenna … that at least should work until the tape is destroyed by the sun.
I suppose you could even use some plastic or wood between the antenna and metal and then wrap tape around it with a spacer at the top and the bottom.
I live in an apartment and have Cell antennas on top of my building and other adjuscent buildings. I had same problem as you have. I solved it by adding a Flightaware Filter between antenna cable and the dongle.
If you can, attach a horizontal pipe to the current metal grille (if it is strong enough) and attach the antenna vertically, 1m or so from the building.
It looks like you are quite high up from the street, so use some proper clamps and locking nuts unless you know the local judge.
You can also add a safety cable to the heavy parts, in case all else fails.
No worries about the current “mount”, that’s temporary for testing only… i have better positions to mount the antenna, where there are no metal parts nearby
Both are same. The label “1090” was on original few releaes. Later it was changed to “1090+978 dual band”.
There is another model of Flightaware filter which is for Europe. It is Dark Blue in color and removes GSM900 band which is in Europe. Since Brazil does not have GSM900, you will not need the Dark Blue one.
I set gain to 30 and omg, so much better! I actually pick up airplanes that fly by my building now. This is amazing, thanks so much! Will monitor this a bit and tweak further if needed.
Oh.
I’ve never seen that … would have thought that count is always less than the total count.
Might have to do with the number of CRC corrected messages maybe i’m not adding them to the total.
Yeah if you get aircraft further away but not close to you … it’s too much gain in 99% of cases.
Glad you’re getting the close by planes, those are often the most interesting to look at after all.
Actually looks like the light blue would be sufficient to reduce the strong interference at 900 MHz and below.
Anyhow … whichever is available to you.
Do you have HDMI devices in that room, that could also be limiting range as it’s picked up by the antenna.
Insufficiently shielded HDMI cables in active use are a regular culprit for having limited range.
The interference is especially bad as it includes the frequency you’re trying to receive so you can only receive strong signals.
The alternative location for the antenna sounds like it would remove that possible issue.
I’ve written a post on how to improve ADS-B reception. It deals with everything from antennas, amplifiers, filters and the software-defined radio specifications as well. Feedback is welcome as I would like to improve it.
Nice entry.
What i am missing is the geographical aspect which limits the range and cannot be improved with any technical equipment.
You should mention the ability via heywhatsthat.com to identify the theoretical max range.
