The purpose of this circuit based on Maxim's MAX9022 is to find faults in multiple cables. The circuit provides an audible signal on a buzzer being powered by 3 small or AAA batteries.
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...