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.
Found in an English Maplin magazine in 1983, this circuit has an RIAA equalization. We suggest its...
This circuit was found in a 1979 magazine. We can use any JFET like MPF102 or BF245. The relay is 12 V...
This beat frequency oscillator or BFO was found in an American 1980s documentation. The circuit is...