This circuit is a four-quadrant multiplier using an LM3900. The circuit was found in the July 1988 Radio Electronics magazine.
Indicated for vinyl media recovery, this circuit is from the 80's, having been found in an...
An interesting application in case of needing to supply an operational amplifier or a very low...
A configuration like the one used with the 4013 is also suitable for the 4027. The amount of time...