GR connector

Designed by Eduard Karplus, Harold M. Wilson and William R. Thurston at General Radio Corporation.

[1] It was widely used on General Radio's electronic test equipment and some Tektronix instruments from the 1950s to the 1970s.

When frequently mated, the inner leaves were susceptible to breakage due to stubbing, flexing and fatigue cracking as the connector was pressed together and alignment was perfected.

In 1961, an optional locking mechanism consisting of an outer hex nut encasing a captured threaded barrel was added to the 874 line.

General Radio, then still a major source of RF test equipment, designed the incompatible GR-900 as a 14 mm successor to the GR-874, filling the industry's need for a higher performance sexless connector for fully reversible lab standards and related test equipment.