This circuit that generates a special sound was found in a Popular Electronics from the 90s. The base is the 555 and the transistors admit equivalents, and a power stage can be added.
This circuit can be used with motors or resistive loads, such as heaters and incandescent lamps....
The output of this circuit can be coupled to a radio control transmitter to perform a...
Using an RCA integrated circuit, this instrumentation amplifier was found in a November 1970 Radio...