Eduard Karplus
Eduard Karplus (September 7, 1899 – August ?, 1979) was an Austrian-born engineer, best known as the inventor of the Variac.
Karplus was born in Hinterbrühl, Austria, the second child of Johann Paul Karplus, a neurophysiologist and psychiatrist, and Valerie von Lieben, a sister of physicist Robert von Lieben.
He graduated from the Vienna University of Technology in 1923. From 1923 to 1929, he was employed in the RF laboratories of C. Lorenz AG, Berlin, Germany, where he worked on mobile high-frequency communication equipment.
In 1930, Eduard Karplus joined the engineering staff of General Radio Corporation in Cambridge, Massachusetts, where he designed and developed measuring instruments, including work on early models of oscilloscopes.
Karplus' best-known invention is the development of the first practical, continuously adjustable variable-ratio autotransformer, which General Radio introduced under the "Variac" brand name (short for "variable AC") in 1933. In the 1940s and 1950, Karplus continued to work on microwave topics such as signal generators, including the design of the GR-874 hermaphroditic high-frequency connector.
Links
- Eduard Karplus @ Wikipedia
Instruments
| Instrument | Description | Literature link |
|---|---|---|
| 419 | Rectifier-Type Wavemeter | 1931-11 |
| 566 | Wavemeter | 1931-10 |
| 687 | Oscilloscope | 1934 (GR Museum) |
| 720 | Heterodyne Frequency Meter | 1945-07 |
| 758 | Wavemeter | 1940-08 |
| 857 | UHF Oscillator | 1944-11 |
| 874-MR | Mixer | 1950-05 |
| 1021 | UHF Standard-Signal Generator | 1950-03 |
| 1208 | Unit Oscillator | 1950-05 |
| 1208-B | Unit Oscillator | 1954-04 |
| 1208-C | Unit Oscillator | 1965-06 |
| 1209 | Unit Oscillator | 1950-05 |
| 1209-B | Unit Oscillator | 1954-04 |
| 1209-C | Unit Oscillator | 1965-06 |
| 1218 | Unit Oscillator | 1955-02 |
| 1750 | Sweep Drive | 1955-04 |