This circuit was obtained in an American documentation from the 80's. The transistors can be equivalent to those indicated and the crystal can reach a few tens of megahertz.
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...