Manufacturer profile
About IET/GenRad
Reviewed 2026-07-26
IET/GenRad is a catalog grouping for instruments from two connected but distinct manufacturers: General Radio and its GenRad successor name, and IET Labs, which later acquired and continued selected GenRad product lines. It is not a single legal company. The grouping helps readers follow manuals for electrical standards, impedance instruments, bridges, decade boxes, and related calibration equipment across that product succession.
History
General Radio was founded in Cambridge, Massachusetts, in 1915 and published its first instrument catalog in 1916. Its early catalog included precision capacitors, decade resistance boxes, variable inductors, and wavemeters. The company later developed a broad measurement range that included impedance bridges, electrical standards, megohmmeters, frequency and sound instruments, stroboscopes, and the Digibridge LCR-meter family.
IET Labs' official history dates IET's own founding to 1975. IET says it began acquiring selected classic GenRad metrology lines in 2000 and continues to manufacture and support General Radio-derived standards, decades, Digibridges, megohmmeters, audio products, and Strobotac instruments. A later transaction with QuadTech covered the Digibridge and Megohmmeter lines. This product-line succession explains why both General Radio/GenRad and IET names occur across closely related manuals without making the companies identical.
Equipment specialties
- resistance, capacitance, and inductance standards
- decade boxes and impedance substituters
- impedance bridges and LCR Digibridges
- megohmmeters and micro-ohmmeters
- sound calibrators, audio instruments, and stroboscopes
Sources
- About IET Labs, Inc. — IET Labs, Inc. (accessed 2026-07-26)
- In the GenRad Tradition — IET Labs, Inc. (accessed 2026-07-26)
- General Radio, esi, IET Labs - Development History — IET Labs, Inc. (accessed 2026-07-26)
- IET Resource Center: GenRad History — IET Labs, Inc. (accessed 2026-07-26)