DC-DC Converter Effeciency

I aquired a car USB charger in need of repair and was inspired by a recent video from the EEVBlog to measure the power efficiency. The device become damaged when the insides flew out during insertion into the 12VDC car jack and the inductor was nearly sheared off the PCB. I was able to reinstall the inductor and slightly modified the circuit for easy measurements and connection to my DC electronic load.

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Single LED Joule Thief Candle

…the thief said “Let there be light. Behold a single candle lit by the joules of a dead cell.”

There is something about LEDs and the joule thief circuit that keeps me coming back. This time around I went for something festive for the December holiday season along with a SMD transformer, no longer will I have to hand wind toroidal transformers.

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RC Radio Backpack Insert

I transport my quadcopter and radio controller using a backpack. I have found it to be more convenient then a large aluminum hard case. I also store a few spare props, prop nuts, tools, and zip ties in it for quick repairs in the field. This arrangement works great with one minor annoyance, the radio is not protected as much as I would like and often times the switches will get bumped during transport. The FrSky Taranis came with a nice hard aluminum case but it is to large to fit in the backpack and too cumbersome to carry to the field, I prefer to carry as little extra with me. With this problem in mind I set out to solve it by making an insert to surround and protect the RC radio.

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