NEW RECORDING MEDIUM 



539 



Fig. 6 — Closeup of recording machine in 3A announcement system at Cleveland. 



The first installation of transcribed message equipment employing 

 this new medium was in the 3 A announcement system at Cleveland, 

 Ohio, to supply weather announcement service. 



The magnetic recording equipment in this installation is a cylinder- 

 type mechanism with associated recording-reproducing amplifier. The 

 mechanism uses bands Ye inch thick, If inches wide and 7t| inches in 

 diameter, stretched over a cylinder 9 inches in diameter. A single record- 

 reproduce head in a pivoted mounting is cam-controlled to trace a helix 

 on the cylinder. The cam is coupled to the cylinder via a quick-change 

 gear train which gives a choice of a three-turn, a five-turn or an eight- 

 turn helix, and the cylinder is driven from a gear-reducer which allows a 

 choice of two slightly different operating speeds. Six different c.ycle 

 times, ranging from about ten seconds to about 45 seconds, are provided 



