Vintage Shure 520SL and Shure 520 SLB Microphones
From the 1956 Shure Brothers Microphone Catalog:
This new Controlled Reluctance unit is designed to handle the most severe field requirement~ of paging and dispatching systems. The unit is supplied with 7 feel of 2-conductor shielded cable, and is wired to ope fate both microphone and relay circuits. The “Dispatcher” is ideal for police, taxi-cab, railroad airport, bus, truck, and all emergency communications work where dependability is vital. Large grip-bar assures positive contact.
(NOTE: Complete assembly furnished as illustrated.)
MODEL OUTPUT High Impedance
LIST PRICE $42.50