RCA PB-90 Velocity Microphone

This is the RCA model PB-90 ribbon velocity microphone from the early 1930's. 

The PB-90 was one of the first velocity microphones made by RCA and may have preceded the famous 44 series.  A 1936 catalog entry shows a somewhat later version of the PB-90, advertised as being suitable for high quality public address applications at about 60% of the price of the 44-B model.

PB-90 Nameplate


RCA PB-90 Microphone

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