This oscillator version is from an RCA documentation from the 1970s. Transistors support modern equivalents and the power can be supplied in a voltage range of 5 to 12 V. For Q2 we suggest the BD136.
This 1964 Electronic Design circuit uses a photo-FET as a sensor. The component is rare today. |...
This metal detector circuit uses an AM radio as an indicator. The radio is placed off-station and tuned...
This circuit is from a 1976 technical documentation. The FET can be MPF102 or BF245 and the coil...