Found in a 90’s Popular Electronics, this circuit uses two CMOS inverters to generate a signal of a few hundred hertz determined by C1 and the R3 setting.
The frequency of this circuit depends on the crystal. The transistor supports a modern equivalent. We...
This circuit is from 1992 documentation, but it can still be assembled today, as the components used are...
Found in an Analog Devices documentation from the 90s, this circuit uses operational amplifiers from the...