Hi to all,
Just wanted to share my findings, it could be of use to someone.
Few weeks ago I noticed sudden drop in number of aircrafts and as my setup C.H.I.P. & FA pro+ was working 24/7 quite some time I decided to check logs first to inspect software first. I saw that dump1090 was running but there was no data and log was full of messages “No data received from the SDR for a long time, it may have wedged”.
Since C.H.I.P. has only one USB port I checked it and found it was quite dusty.
OK, just quick check, antenna was ok, cables connectors all ok, and measured power supply with fluke multi meter and it was steady at 4,9V at input and 4,85 at USB port.
I disassembled FA stick, at first, nothing suspicious, solder on SMA and USB connectors was ok.
I “washed” everything in ultrasonic bath with isopropyl alcohol and assembled it next day.
To my surprise errors showed up again, dump1090 produced some data for 2-3 minutes, than error repeated. On every restart it was working few seconds to minutes…
So, dead dongle?
I put it in windows machine directly in USB port and it was working longer but still acting strange, it hangs after 10 or more minutes, but lasts more than C.H.I.P. Quick look again and measurement, I found that my PC is putting 5,1V on USB and that gave me idea.
Removed 2 electrolytic capacitors and measured them with cheap LCR meter, they were labeled 10V 220uF and measurement showed 70-100uF, nothing near declared capacity. I didn’t have new 10V cap in my spare parts, so I put 16V but same capacity. Because it was little bigger, I soldered it at 90-degree angle.
And voila! It works! For last 3 weeks it didn’t stop not a single time.
I was prepared to throw away dongle because I had few others used on other projects, from generic plastic ones, some of them died in similar way because RTL2832 chip dies. Those generic have no cooling, no solder on thermal pad below chips, poor quality power supply etc. V3 from rtl-sdr.com is great solution for long run but there is no filter for 1090 or LNA in it.
So, after few years of constant use I recommend changing those capacitors and if some of you did have similar issues don’t throw it away because this could be cheap fix and should work for few more years for sure.
Sorry for long post