Anime girl with a calculator, a breadboard and a notebook with a schematic drawn on it. The schematic is a linear voltage regulator (opamp with Zener reference, followed by a MOSFET pass transistor). Book cover of the Marmalade magazine Issue 2, a fandom hobby electronics magazine, published in Dec. 2016 at Comiket C90. Features articles: How To Make a Digital Oscilloscope (continued) & Electronic Hydrometer.
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