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NORMAN E. WUNDERLICH was born in Chicago, Illinois, in 1899. He has had a great variety of radio experience, having been employed by the Marconi Company in 1917, the United Manufacturing Company of Chicago, Neutrowound Radio Manufacturing Company, the Carter Radio Company, the Victor Talking Machine Company, and the Audio Vision Appliance Company. In 1918 he was an instructor in the United States Naval Communication Service. For two years he was editor of the Radio Topics Magazine. He organized the Victor engineering staff and laboratories, and is now chief engineer, Audio Vision Appliance Company, laboratory of the Radio-Victor Corporation. He is a member of the Institute of Radio Engineers, the American Institute of Electrical Engineers, and the Radio Club of America.

William F. Diehl began his radio work with experimentation at Bayside, Long Island, New York, in 1907. For nine years he carried on amateur and experimental radio work. He organized and was president of the Flushing High School Radio Club. He organized the Bayside Radio School, to prepare students for Commercial Operators' Licenses. He has been associated with the Western Electric Company, E.J. Simon and Company, the Manhattan Electric and Supply Company and the A.H. Grebe Company. He is now assistant engineer at the Audio Vision Appliance Company, laboratory of the Radio-Victor Corporation. He has been an instructor in various radio schools, and during his service with the United States Navy contributed much to the field of radio advancement. He is a fellow of the Radio Club of America, and an Associate Member of the institute of Radio Engineers.
(LEFT) An endless belt conveys the chassis to and from meter panels where continuity tests are made. (RIGHT) Close-up of test board showing plugs which replace tubes during a test. Connections from plugs lead to a set of tubes behind the panel which function as they ordinarily would in a receiver.

Laboratory Tests in High-Speed Production
Radio-Victor Receivers, Turned Out at the Rate on One Every Eight Seconds, Are Subjected to Precision Tests and Rigid Inspection.
By Norman E. Wunderlich and William F Diehl, Radio News, January 1930

From bare floors to the production of more than 5,000 precision-tested radio receivers per day by 13,000 employees is in truth an accomplishment, but when it is done in the brief span of twelve weeks it establishes what is believed to be a new record for the radio manufacturing world. Who can say that such an achievement lacks thrills throughout every step of the transition?

Less than a year ago thousands of square feet of floor space were occupied by machinery for the manufacture of Orthophonic phonographs. Many months of intensive research activity had preceded the final design of the radio receiver. The task of getting production started was approached in a manner very different from the usual procedure. Thorough and complete engineering analyses were made of every kind of material that was to go into the finished product, for it was to be the finest that human ingenuity could produce in order to be a worthy successor to a long line of musical instruments. These reports, covering the sources of raw materials, were exhaustive, analytical and comparative. The manufacturers themselves were investigated to determine their ability to produce supplies of the required standard. When orders were finally placed, a representative of the Radio-Victor Corporation was stationed at each factory to keep a careful check of production.

Over two hundred of these reports were prepared by the engineering department during 1929. The Victor engineering department's original design considerations include all of the technical data and production specifications going back as far as the chemical analysis of raw materials, and leading step by step through the details of fabrication to the final check of performance characteristics. Delailed specifications covering all materials, component parts and completed instruments, were compiled and published from the preliminnry engineering work. These specifications contained the fewest restrictions and widest possible tolerance, both mechanical and electrical, consistent with obtaining a high standard product.

It was necessary to design new tools for the production of the 11,000 individual parts going into this new set. Rows of 250-ton punch presses and many other types of machines were installed, and among them were threaded conveyor belts and overhead curriers, operating between elevators. Within forty-five days production of completed units reached the 2,000 mark. Six weeks later the peak of 5,000 per day was attained. Other manufacturers have achieved quantity production, but we believe that our organization excels in the thorough and exhaustive tests to which all Radio-Victor receivers are subjected before their final preparation for shipment. Every receiver is measured for sensitivity at five different carrier frequencies (553, 711, 948, 1264 and 1501 kilocycles). The response runs from one to seven microvolts per meter. Test equipment, costmg a quarter of a million dollars, has proved to be a splendid investment, bringlng consistency in the product, reducing waste, and making for a trouble-proof instrument. Shortly after production had got under way the engineering department established and maintained a radio school for foremen in the factory, the course given Iasted over a period of six weeks, and in some classes there were 200 studenls. The training stepped up production and brought about a marked decrease in rejects. An arrangement was perfected which would permit the testing of 5,000 receivers a day at five different carrier frequencies. Ten cryslal-controlled oscillators--five together with auxiliaries--were installed in a double-shielded room. Copper tubing shielded the driver leads belween generator and the tesling benches. Measurement is made by visual indication of the entire frequency response and audio gain characeristic of every individual audio transformer and the over-all response of the complete amplifier unit.

(LEFT) Five-channel dual-crystal, temperature-controlled signal-generator. (RIGHT) Alignment and receiver-testing station. Pipes, underneath the bench, convey five standard frequencies from the signal generator to the attenuators.

The testing equipment is inspected twice daily by a group of fifteen testing engineers who devote their entire time to observing test equipment and maintaining it at the highest standard.

Very interesting experiments were conducted involving the installation of loud speakers in suffcient numbers throughout the manufacturing division to make reproduction of phonograph records audible above the noise of machinery. It was found that lively tunes increased production, and slow music had the opposite effect. In the summer these loud speakers conveyed the World Series baseball scores to the workers. Lemonade was served in the afternoons, and a cafeteria has been provided for the convenience of the employees.

Accompanying this article are some views of the standard test equipment, signal generators, and apparatus for complele analysis and measurement of both radio and audio-frequency amplifiers. Bungalow atop the engineering building houses an acoustic laboratory.

Engineering is by no means confined to the laboratory, for groups are continually in the field making performance tests of new models, working out problems of the merchandising organization, and keeping in touch with the activities and methods of other factories. Within this scope comes everything from the writing of initial specifications to the checking up on proper performance and satisfaction in the field. The executive policies which gave wide authority and liberal financial support to the engineering phase of this project left no uncertainty as to the results which were desired and expected.


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