A New Recording Medium For Transcribed 



Message Services 



By JAMES Z. MENARD 



(Manuscript received March 10, 1952) 



A magnetic recording medium composed of rubber impregnated loith mag- 

 netic oxide and lubricant is particularly suited to applications requiring 

 the continuous repetition of short transcribed messages. It affords excep- 

 tional life, reliability, and economy in telephone applications, where it is 

 utilized in the form of molded bands stretched, over cylinders of the recording 

 mechanisms. 



In the Bell System there are several applications requiring the repetition 

 of short voice announcements. Some of the existing applications are 

 weather announcements, intercept of calls to vacant and miassigned 

 numbers, quotations of delays on long-distance calls, and certain leased 

 industrial services, such as stock price quotation. Most of these require 

 continuous repetition of messages between 5 and 60 seconds in length. 

 In some the message remains fixed but in others it is changed at frequent 

 intervals. 



Magnetic recorders offer particular advantages for services of this 

 nature, because they require a minimum of equipment and operating 

 skill to produce durable records which are instantly reproducible without 

 processing. For several years the Bell System has used a magnetic re- 

 corder employing a loop of Vicalloy tape in the 3A announcement system 

 to furnish weather announcements, and a similar tj-pe of recorder has 

 been used in a leased industrial system at the New York Times. 



Recently these Laboratories have undertaken the development of 

 transcribed message facilities to meet additional service applications. It 

 was required that the new facilities should provide satisfactory trans- 

 mission quality and afford considerable flexibility in regard to message 

 length, but the paramount requirement was for reliabilit.y and long life. 



It did not appear practicable to extend the techniques of the Vicalloy 

 tape machine to give the flexibility, convenience of operation and re- 



630 



