nRF24L01+: Fixing the “magic finger” problem

This time I was spending the holidays as usual away from the city, further improving my smarthome. This time I was installing a bunch of devices with nRF24L01+ radios. When I was running out of spare nRF24L01+ modules, I noticed that I was left with a bunch of weird modules that kind of work, but really crappy. They feature huge packet losses, but whenever you touch the PCB antenna, it goes away. I decided to look into the problem and document my findings.

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Pssst, dude! Wanna some secondhand chips?

There are many wonders in electronics land. Even more await an engineer that stocks up at aliexpress to save a bit on his hobbies. Well, I needed a few RTC chips for some prototype hardware, so I picked DS1307. As usual, placed an order at aliexpress. once in a while shit happens .

No, this time they didn’t write ‘sex toy – 3$” on the customs declaration sticker, as they did on a parcel with a dozen of TRIACs a few weeks ago (Or, did I use TRIACs wrong my whole life! Should have asked them for instructions!)

Anyways this time I received some second-hand chips. Packed in a plastic tube, no flux whatsoever, but small solder blobbies are all over the pins. Without unpacking, I’ve made a few pics. Sorry for the quality, but I put my USB microscope somewhere far and my usual camera doesn’t handle focusing on something that close well.

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