This interesting circuit for the RDA8851 allows you to obtain two volumes with a simple touch. The circuit is from an Electronics Now from December 1988. Note the amplifier voltages.
This circuit allows you to modify the resolution of a measurement bridge. It was found in the...
The four gates of a 40111 IC are used in thes two-out circuit. The output chages their state in a...
This circuit measures the strength of audio signals. We found it in an American publication from...