Pioneering Work

First or Among the First to Introduce:

General Radio founded in 1915
1915 Condenser
1918 Decade Bridge
1920 Variable Air Condenser
1923 Invented the Binding Post
1923 Direct Reading Wavemeter
1926 String Oscillograph
1927 Direct Reading Ohmmeter
1928 Vacuum Tube Bridge
1929 Output Meter
1930 Decade Resistor
1930 Decade Condenser
1930 Piezo Electric Oscillator
1931 Frequency Meter
1931 Vacuum-Tuber Voltmeter
1933 Impedance Bridge
1933 Noisemeter
1933 Microvoltmeter
1933 Volume Control
1934 Oscilloscope
1935 Variable Inductor
1936 Megohmmeter
1937 Sound Level Meter
1937 Voltage Divider
1938 Variac
1932 Edgerton Stroboscope
1940 Broadcast Frequency Monitor
1956 dc Amplifier and Electrometer
1956 TV Transmitter Monitor
1961 Tuned Amplifier and Null Detector
1976 Modern LCR Meter "Digibridge"
and much more…Improvements on these and other products continued in the years that followed…


esi founded in 1944
1960-1970’s SR-104 0.5 ppm Resistance Standard
1960-1970’s RS925 First 20 ppm Resistance Decade Box
1960-1970’s 242D First 10 ppm Resistance Measurement System

IET Labs founded in 1975
1975 RS/CS/LS Series Thumbwheel R-L-C Decade Substituters
1977 DM-45 First Pocket Autoranging DMM
1979 CM-500 Capacitance Meter
1980-1990’s- PZS-First Programmable R-L-C Decades
1980-1990’s- SRL-High Accuracy Resistance Standards from 1 mΩ - 10 TΩ
1980-1990’s- HRRS-High Resistance, High Voltage Resistance Decades
1980-1990’s- KVD-High Performance Kelvin-Varley Voltage Dividers
2000 IET Acquires GenRad Classic Product Line
2002 Expanded the 1482 inductance series from 1 uH - 100 T
2004 Released Capacitance Standards as high as 10,000 µF
2006 IET Acquires GenRad Megohmmeters and Digibridges
2006 IET Acquires esi Resistance Line
2009 SR103; 0.5 ppm stability resistance standards at 1 kΩ
2010 The 1865+ Megohmmeter
2011 1404 10 nF Capacitance Standard
2011 Upgraded the Digibridge IEEE Board

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