The operational amplifier for this tone control found in a 1977 Signetics manual may be the 741. The power supply must be symmetrical and the signal cables short. The bass gain is 20 dB.
This circuit uses a simple power source, having been found in the Philips Databook of 1990....
This circuit is suggested by Texas Instruments in its Linear Circuits Applications. It is a...
This circuit generates a pulsed tone whose frequency depends on C2 and whose flashing depends on...