This circuit for very low frequencies was found in an American documentation from the 90's. Transistors are for general use and the frequency depends on C1 and C2.
This astable multivibrator configuration causes two LEDs to alternately flash at a frequency...
In the figure we show our first circuit that consists of a simple touch switch capable of driving a...
This electromyography monitor is from a 1978 publication on operational amplifiers. The components are...