Here are the final steps of assembly and testing of my new Bob Parker Blue ESR meter from AnaTek. It can measure many capacitors for their equivalent series resistance (ESR) while they are still in the circuit! The low test voltage helps keep ordinary semiconductor junctions from conducting during a measurement.

Capacitors should still be discharged before testing, and an ambiguous in-circuit result may need a capacitor removed for further investigation. No more removing capacitors? Well, fewer - unless I’m in the mood, of course!

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