Now [jgpeiro] has made one which is light years ahead of the toy kits, using a Raspberry Pi Pico, a 100 MHz ADC, and an effort ... being set by a series of DAC chips under software control.

[Bram] decided to make his own, powered by a Raspberry ... Pi from the 3.7V battery, a charge controller and a battery protection circuit. As a bonus, the battery voltage is monitored with a 12 ...