| 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 |
| 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 |
