This conventional filter circuit is from American documentation from the 1990s. The operational amplifier admits an equivalent and the power supply must be symmetrical.
In this circuit of the 80's components of the time are used. The circuit controls a direct current...
This is the basic operational amplifier configuration for gain 10. R2 can be changed to other...
The CMOS 4046 integrated circuit is not very common today, consisting of a very efficient PLL for...