The constant pi, or π , is one of the oldest and most recognizable irrational constants. It was
known from the earliest days of mathematics and the sciences. Over the ages, many methods of varying
complexity have been used to estimate π . This article presents a novel experimental method to
estimate π using direct, digital voltmeter measurements on a simple precision full-wave rectifier
circuit. We discuss the method in the context of error encroachment, and suggest the possibility to
estimate total harmonic distortion simply. The experiment is repeatable and of value to the
undergraduate physics and electronics laboratory, while adding to a celebration of π .