Assorted Voltmeters and Ammeters (c. 1942)

DC Voltmeters & Ammeters 

The voltmeters and ammeters in the image represent the evolution of analog monitoring technology, spanning from industrial audio applications to rugged military and aerospace hardware. The largest meter on the left is a product of the Simpson Electric Company, a pioneer in the instrument industry chartered in 1934. This specific "wide-view" style, featuring the iconic Simpson cursive logo, became an industry standard in the mid-20th century for its clarity and precision. The scale shown, ranging from 0 to 100 with a red "warning" arc, is characteristic of a VU (Volume Unit) meter or a percentage-load indicator, frequently used in radio broadcasting and early recording studios to monitor signal levels and prevent equipment overloads.

The two smaller, circular-face meters on the right are classic examples of "pizza-box" or "standard 2-inch" aircraft instruments, likely dating from the World War II era or the early Cold War. These ruggedized DC meters—measuring Amps and Volts respectively—were designed to withstand the high vibration and extreme temperatures of a cockpit or military radio rack. Their distinctive black faces with gold or yellowed high-contrast markings were engineered for maximum legibility under low-light conditions, often using phosphorescent paint so pilots could read them in the dark. While Simpson produced many such meters, companies like Weston Electrical Instrument Co. and Westinghouse were also major suppliers of this specific "Deco-style" aviation hardware, which helped standardize electrical monitoring across global defense fleets.

Donation: John & Carol Babina Jr.