Is the increase due to more weekday flights (15-18 July) versus weekend flights (13-14 July) in your location?
The scatter plot does account for that somewhat - if the increase were solely due to more traffic, you would expect to see two similar curves, but with the busier days having more points at the end of the curve. What the plot is showing is that the busier days did have more aircraft, but that more messages were received for every number of aircraft - ie, the blue dots are clustered higher than the red dots all the way along the line, so this does seem to indicate better performance of the receiver.
You do raise a valid point though - it is definitely better to try and compare longer periods with each other than one or two days at a time, as that will help reduce any day to day variability.
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Excellent script!
I modified the script for run automatically the gain optimization tool each hour to get optimal results all day.
I have 7 locations in Costa Rica, but 5 was down, and i am thinking that the reason is gain in max value and equipment saturation… i will try with your script.
Thanks a lot!
Saturation and extra heat, perhaps.
Higher gain is not necessarily better. Just for ‘fun’ I lowered the gain from 49.6 to 29.7. Looks good enough to leave it like that for a few days and check again.
Much more likely the power supply is bad.
Or the dongle didn’t like the heat.
Too much gain can result in bad reception, but wouldn’t cause the station to be down.
That’s fairly conclusive 
Is that with LNA or without?
And the airspy is that without LNA as well?
Both with uputronics 1090 mhz ceramic filtered preamp
One can definitely notice by the gain numbers that your antenna is quite obstructed 
Today i took the free time and played around with the gain.
I switched from 49.6 back to max/agc which did not change much except the number of messages > 3dB which increased again up to 8-12% in average
Then i changed the setting to a lower value of 42.1 and let it run for a while
Except the reduced number of messages >3, signal level and the CPU usage of ADS-B nothing seem to have changed.
The number of aircraft is the same, number of tracks seen etc is all the same/similar to previous hours/days with similar traffic. The range also did not change so far
I am using as you might know already the blue FA pro plus stick with a modified indoor antenna on a can.
Does this mean the changes does not have that much impact because i am not using an “optimal” physical setup? Or is the change between max and 42.1 that low?
EDIT: Just have seen this thread. seem to be that the values of 40 and up did not change a lot on the pro plus stick.
The change between max and 42.1 is actually quite large. It’s possible however, that if your antenna is blocked by obstacles or terrain, you are already receiving everything inside that range, so increasing the gain isn’t increasing the signals significantly - any increase from getting marginal signals could be easily offset by losses from oversaturating the strong signals.
I take it from your previous post that you are using the mag-mount antenna cut down to the correct length? If so, then you can likely increase your receiver performance a lot by swapping it for a simple home made antenna (or one of the pre-made options you can get).
See one of abcd567’s many threads on building and optimising antennas - the spider based on a chassis socket is a good place to start:
And some graphs showing it.
Until 0900 the gain was set to 49.6, between 0900 and 1300 it was at max/-10 and changed to 42.1 since 1300
As said before I would leave it at 49.6. 
Just out of curiosity regarding the amount of messages compared to mine, what is in your /etc/default/dump1090-fa? (I never get more than > 800 msg, unless I enable "Mode-AC.)
So can you post the output of cat /etc/default/dump1090-fa, please?
Sure, here we go. Still with setting the gain to 42.1
# Generated automatically by /usr/lib/piaware-support/generate-receiver-config
# This file will be overwritten on reboot.
ENABLED=yes
DECODER_OPTIONS="--max-range 360"
NET_OPTIONS="--net --net-heartbeat 60 --net-ro-size 1000 --net-ro-interval 1 --net-http-port 0 --net-ri-port 0 --net-ro-port 30002 --net-sbs-port 30003 --net-bi-port 30004,30104"
JSON_OPTIONS="--json-location-accuracy 2"
RECEIVER_OPTIONS="--net-bo-port 30005 --fix --device-index 0 --gain 42.1 --ppm 0"
From the number of messages it’s almost all the time shown as factor 10 compared to the aircrafts seen. Sometimes more, sometimes less. No idea if this is good or bad.
I’ve had up to 1400 using the rtl-sdr v3 stick with LNA.
And with the Flightaware ProStick+ i believe my maximum message rate was 1200.
It’s not unusual for Europe.
Seems your receiver can’t quite see in all directions, normally you should get lots of messages/s being in the Netherlands.
Might also be a problem with interference.
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Can you add a text at the end of the run to point to the location address of the plot?
rtl-sdr stick with the rtl-sdr LNA gives me a peak message rate of about 1780 messages/s. I’ve never seen it crack 1800 however.
What script do you want that adding to?
