This crystal oscillator is indicated for the calibration of IF steps of common radio receivers. The transistor admits equivalent as 2N2222 or BF494. The circuit is from an old American publication.
This circuit is from a 1992 publication. The transistors can be the BC549 or BC548 and the power...
This receiver for frequencies up to 18 MHz was found in American documentation from the 1990s. Data...
This toy musical instrument has the notes given by the capacitors on the keyboard. The circuit can be...