Education, Vintage Electronics and other projects

Beat of two close sine waves

Beat of two close sine waves — quasi-AM effect (click to play video)

Raspberry Pi and Arduino boards

Raspberry Pi and Arduino — two different souls: a microcontroller and a computer (click to read)

Analogic C4 telephone ringer

Analogic C4 telephone ringer

Accuracy versus precision targets

Accuracy vs. Precision — two words used as synonyms, two different things in the laboratory (click to read)

Numitron clock test

Numitron clock test. RCA tube, 7447 decoder.

74xx47 seven-segment decoder

The 74xx47 BCD-to-seven-segment decoder — a 1974 part, and a truth table you can drive (click to try)

Lissajous figures on a Tektronix T912

Lissajous figures displayed on a Tektronic T912, 70’s green phosphors oscilloscope. (Courtesy P. Ceccarelli)

Crystal AM radio with OA90 germanium diode

Crystal AM radio using a OA90 germanium diode as detector (no power supply)

Neon lamp-based oscillator

Neon lamp oscillator: capacitor charge through 1 MΩ resistor → 68 V gas breakdown → C discharges → cycle restarts (click to play)