eMeter - handmade ultra-compact multimeter with oled display. Slightly larger than a pen
Specifications: VDC = -40...+40VDC R = 1R...4Mohm, C = 1pF...200uF, Oscilloscope: 1 megasamples max, but also shows periodic signals, with a frequency of 8-20mhz. -3...+6V signals on display. Adaptive voltage range and scan rate.
Internal Li-ion 120mAh. 5-7 hours of work. Charge mode.
Youtube: https://youtu.be/8Z2Uotad20s