This traditional crystal oscillator configuration can use any CMOS gate configured as an inverter. R1 has values from 1 to 5 M ohm and R values around 10 k.
This circuit, suggested by National Semiconductor, is a tone control (bass and treble) with high...
This circuit from a Japanese publication in 1968 uses germanium transistors from the time like the...
This circuit is from a publication by Newton C. Braga in the United States. The transistor can be...