This circuit is from a Motorola documentation from 1968. The integrated one is an operational of the time still in metallic casing. Modern equivalents can be used.
Found on Popular Electronics this circuit has variations found throughout this site and section....
This effect for guitar was found in an English magazine from 1978. The transistors can be the most...
This circuit was found in a 90s Popular Electronics. It is possible to analyze the voltages of an...