Microdot connector
Microdot, a company based in Irwindale, California and now owned by Tyco Electronics manufactures a wide range[1] of coaxial and multi-pin connectors that have been used since the 1950's for instrumentation and aerospace applications. While the company makes various proprietary and industry-standard connectors, they are best known for a small coaxial connector which has become known as "the" Microdot connector. In its most common version, called the S-50 series, it uses a 10-32 (0.190-32 UNF2B) thread. This connector is used worldwide for accelerometers, small microphones and various other transducers.
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