AVOmeter is a British trademark for a line of multimeters and electrical measuring instruments. The first AVOmeter was made by the Automatic Coil Winder and Electrical Equipment Co. in 1923, and measured direct voltage, direct current and resistance. Possibly the best known multimeter of the range was the Model 8, which was produced in various versions from May 1951 until 2008; the last version was the Mark 8.
In 1966, AVO moved from London to new premises in Archcliffe Road in Dover where they are still located. In 1987, a management buyout re‐named the company Megger Instruments Ltd.
The multimeter is often called simply an AVO, because the company logo carries the first letters of 'amps', 'volts' and 'ohms'. The design concept is due to the Post Office engineer Donald Macadie, who at the time of the introduction of the original AVOmeter in 1923 was a senior officer in the Post Office Factories Department in London.