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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RTL-SDR & Static protection.

Okay, I also got myself an rtl-sdr dongle and it rocks. However, just a tip.
If you ever think of connecting an external antenna – have a GOOD look at the PCB. Some dongles are missing ESD protection. Like the one I got myself from ebay.

If so, connecting a big external antenna will result in a dead dongle. The ESD Protection is BAV99, according to the reference schematics.
Thnkx for exception13 for drawing my attention to this issue.
You can get those for about 7 bucks for 100pcs at aliexpress with freeshipping.