FlightAware Discussions

PiAware 5.0 and Gain setting — Resolved

Edit - must have been operator error or cosmically flipped bit. Gain works fine.


It looks like I am not the only one. I was doubting myself, as after updating to version 5 I am having the feeling that I “see” less planes. (about 20%)I did not change my gain or anything else.
So perhaps the new update doe something to an exciting setup.
Guess it is weird, but I am “glad” I am not the only one who noticed a difference.

Curious if there are others or if someone as a solution.

No, this has not changed and the core demodulator is also unchanged. There were some changes to the decoder, but that wouldn’t have a dramatic effect like you see.

Thank you, @obj. I don’t know why the difference but maybe it was update related. I had rebooted after the update but when I set the gain to 37.2, it collapsed the range way down. After seeing your reply, I went back and tried other gain settings and was able to change the effective range from fairly close in (but nowhere near as close as before - maybe about 100nm vs what looked like 25nm earlier today).

Anyway, after a few other gain values to watch the range grow and shrink, I tried 37.2 again and it worked. Only thing I can figure is I typoed or something. Gain does indeed work as it did before and my bad.


I have upgraded to Ver 5.0, but by re-imaging with piaware sdcard image ver 5.0.
I do no notice any change in range.

Before upgrade, with an indoor mag-mount antenna over a metallic plate, and Gain setting 38.6, I used to get up to about 200 nm.

After upgrade to Ver 5.0, I still get the same range with the same antenna and same Gain setting.

I don’t know what happened, abcd, but gain seemed knockered after update and reboot when I tried adjusting the gain 1090-fa gain value as noted above. I tried a couple of settings but the only one that seemed to work was -10 for AGC/max gain. I set it aside and posted here if anyone had noticed anything similar.

After obj confirmed there was no change to how you set gain, I went back but this time everything worked as expected. I have no idea why. I don’t know what was different but the most likely answer is PBKAC. When I first set gain to 37.2 and restarted the daemon, I could only see two aircraft at an airport about 5 miles away. At -10, I was seeing 90 or so just moments before. I was just restarting the daemon to pick up the new value each time and not rebooting between tries and watching the results on my PiAware web page. It was actually a pretty cool refresher on the magnitude of the range changes.

But what threw me was how that first 37.2 gain value took almost all, but not quite all, planes off the map. It was still working but really badly. When I was trying the extremes again when it was working properly, no setting dropped the activity to just airplanes within whatever limited range I had this morning but I wasn’t comparing to the FlightAware map to see where the range actually stopped. So hand-wavy. But I wasn’t able to replicate the range issue with the values I was using. I don’t know the guts of the chip or the software but maybe I somehow set other bits or something, or I’m just old and my eyes deceive me.

Anyway, it all works now. Thanks, though!

May be typo. You may have typed 3.72 instead of 37.2 in the settings. :wink: