This circuit was found in the August 1996 Electronics Now magazine. The circuit is based on an operational circuit whose type determines the gains and limits for the frequency.
In the figure we show how to use a 555 to control an SCR or another type of thyristor. Resistors R1, R2...
This circuit was taken from the 1974 Ferranti transistor manual. Transistors are common types at...
This interesting intercom circuit was obtained from an Argentine publication from the 1970s....