Found in a 90s documentation, this circuit makes use of D1, a switching diode that is uncommon today. D3 is an LED. The circuit monitors 12 V batteries.
This circuit can be used in decoration or to draw attention, in a “fake” assembly for example. What he...
This filter was found in Exar documentation from the 1980s. The circuit has an attenuation of 60 dB at the...
This windshield wiper timer was obtained in an 80's Hands On. The transistor can be the BC548 and...