F4 Replacement on the RF Revolt

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Very nice video! Most of what you show is not only true for the Revolt but also for most of the other F4 FCs.

I can confirm the way F4s “short out”. Instead of plugging it in you can also check for continuity between the 3.3v rail and GND, if it beeps - it’s probably dead.

I for myself prefer the “poor mans” reflow technique (clean the pads completely with desoldering wick, add a little of my favorite solder to all pads, apply flux (a lot), align chip, reflow with low airflow), but I also do drag soldering or the “tappy tap” technique you seem to prefer.
Not sure whether there’s something like “the best technique”, all get the job done. Regarding thermal stress “tappy tap” and drag soldering are probably a bit more safe than reflowing things again.

I have the feeling I maybe use excessive amounts of flux, but there’s nothing isopropyl and an old electric toothbrush wont clean of the board!

Great video, @Denovich. Nice to know you appreciate espresso as much as I do.

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In the video I blame the espresso, but it is just how I’m wired. I’ve always had shaky hands that get more shaky the harder I try not to have them shake. When I started shooting archery, I experimented with no caffeine for a few weeks but saw no improvement (and suffered some crushing headaches). The upside is that I must vibrate lots of calories away… I eat a huge amount, with few repercussions.

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