| 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… |
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| 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 |
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| 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 |
| 2013 | HPRS-Hipot-Load High Power Resistive Load |
| 2014 | Redesign of LOM-510A Milliohmmeter |
| 2016 | Released PRS-300 Programmable Decade Resistor |
| 2018 | Redesign of 1986 Omnical Sound Level Calibrator |
| 2019 | Released SRAC ac Standard Resistors |
| 2019 | Released PRS-330 Programmable Decade Resistor |
| 2019 | Released PRS-370 Self-Adjusting Programmable Resistance Decade Substituter |
