FlightAware Discussions

New Pro Stick Plus and FA Antenna - Less Close Range Tracking


#1

I have two ADS-B tracking setups about 4 miles apart. I am in northern Illinois about 70 miles west-northwest of Chicago. I track a lot of traffic in and out of O’hare airport.

For years both setups were identical using the stock FA PiAware setup for RPi with the PiAware Skyview. Both had a basic SDR dongle and a home made 4-leg spider with the antennas outdoors about 25 ft high above ground. They both track about the same coverage.

I recently upgraded one of my ADS-B setups to use a FA Pro Stick Plus dongle and the FA antenna. Before upgrading most of my tracking coverage was less than 100 miles. The new setup has greatly increase coverage in the 100-150 miles range and even pickup some in the 150-200 miles range. However, with the new setup I have lost nearly all coverage under 50 miles.

Here are two coverage charts showing before and after the upgrade.

If I had to guess I would say the cause of the under 50 miles coverage loss is due to the FA antenna and not the Pro Stick Plus dongle. But I’m not sure. Maybe there is some new configurations I should do to the PiAware software that I don’t know about?

I have a new cable on order so I can try my old spider antenna using the Pro Stick Plus dongle. Then I can see what that does to my coverage map. But it might be a few weeks before I can try it out, maybe longer if we get snow and winter sets in.


#2

It appears that you are seeing further so out is probably safe to assume both the antenna and dongle are working well.

If i had to guess i would suggest that the signal strength is too high for the close in planes and you may need to lower the gain in Piaware.

S.


#3

The closer signals are too strong now and get clipped. Adjust the gain at around 30-36 dB or so…


#4

I tried adjusting the gain a couple of weeks ago with no changes. But I just found adcd567’s post on how to adjust the gain and I wasn’t doing it correctly. I was trying to adjust the gain by using the command line but since I had a Raspbain image setup I need to edit the “dump1090-fa” config file manually.

Now I actually have the gain set at 30 and it looks like I am now tracking “local” aircraft again. I’ll wait a day or so and check my coverage map to see how it has changed.

Thanks Sweepea11 and SoNic67 for the help. And thanks abcd567 for your tutorial.

FYI, here’s abcd567’s post on how to set the gain: