This circuit is from a 1966 publication. The frequency depends on the capacitors and on R1 which can have values between 47k and 2.2 M typically. The supply voltage can be between 200 and 300 V.
On this 1960s circuit, stations are pre-tuned in trimmers and then selected by a switch. The...
This small shaver bender circuit makes it possible to use 220/240 V shavers on 110 V networks. The...
The operational amplifier used in this application is not the most common today. The circuit is...