Found in an Electronics Now from the 90s this mixer has several inputs. The integrated circuit can still be found easy and the power supply need not be symmetrical.
This circuit with TTL output was found in a 1968 EEE. The transistor can be of general use. The...
This 100-second timer was found in a 2000 Poptronics. The magazine no longer exists, but the...
This control for a small servomotor with a current of a few hundred milliamps was found in an...