This circuit was found in an old documentation, being able to generate signals of frequencies in the range of 50 to 100 MHz. The components are of the time.
This receiver with two common JFETs was found in an old English documentation. The phone is...
This TTL circuit with the 7493 makes the binary count of the pulses sent by a flip-flop with the...
This circuit was found in a Popular Electronics from the 90s. The counter circuit is not common...