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Albert D. Silva

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Albert D. Silva who was born on August 9, 1888 to Albert and Sarah Silva. One of eight children, he was educated in Newport, Kentucky where he graduated from high school. From there he attended the University of Kentucky for one year, and in 1908 he enrolled in the Ohio Mechanics Institute in Cincinnati. Upon completion of that school he went to Schenectady to the General Electric Training School which he finished in 1911. General Electric hired him that year and assigned him to the Transfonner Division in Cincinnati. By 1913 he was transferred to the Illuminating Division in Cleveland. At GE he acquired the nickname "Duke" which was to remain with him the remainder of his life.

In 1917 he was sent to Ft. Benjamin Harrison in Indianapolis, Indiana where he received a commission as a Lieutenant in the Signal Corps. His first assignment was at Camp Alfred Vail in New Jersey. Later renamed Fort Monmouth, Camp Alfred Vail was intended to provide laboratories for the Signal Corps when their facilities at the Bureau of Standards in Washington became inadequate. Along with other scientists and technicians, Silva produced copies of Allied radios, improved on previous designs and provided drawings and specifications for the various manufacturers of official Signal Corps sets.

After completing the Army's Signal School in 1918, Silva was sent over to be a part of the Signal Corps American Expeditionary Forces in Paris. Silva met Major Armstrong and became friends with him. Silva was placed in charge of the Tank Corps of the AEF and designed a modified E-10 series used in connection with a trailing antenna so the tanks could communicate with one another. After considerable experimental work, Capt. Webb left for the United States produce the radio set. Work was continued by Silva and Sergeants Pressley and Newell, and considerable improvements were made in the antenna current output. Using Armstrong's idea of a circuit employing one tube as an oscillator and one or more tubes as power amplifiers, the apparatus was successfully installed in a Renault signal tank. The antenna used was similar in construction to a Bristol rod and extended 15 ft. above the tank. Later it was felt that an umbrella antenna 6 ft. high with arms of 4 feet in length was equally as satisfactory.

On March 25, 1919 to AprilS, 1919 he was returned to the states and assigned to the Office of the Chief Signal Officer in Washington D.C. whereupon he resigned from the Army. From December 1919 to May 12, 1922 he was the civilian in charge at Camp Alfred Vail. Shortly after leaving his civilian job the "Duke" was employed by Atwater Kent as an engineer. Atwater Kent was ready to get into radio in a big way because he had the machine tools, bakelite molding equipment and a dealership network in the auto industry. So plunge they did. By 1924, Hazeltine had developed a system to neutralize the triode vacuum tube and he formed the Independent Radio Manufacturers :lIl association to compete against RCA. Atwater Kent like many other manufacturers didn't want to pay the royalties. Besides some companies couldn't remain competitive if they did. So A. D. Silva designed an amplifying apparatus shown in the text. It was filed July 26,1924 and awarded the patent number 1,885,301 in December 4, 1934. This application contained the famous grid resistors which collectors often have to replace. These resistors of approximately 600 ohms stopped oscillation in the set but as Serge Krause a former repairman and engineer said it also reduced the sensitivity of Atwater Kents. He said that as a repairman they often cut the resistance down to the point of oscillation in an effort to improve sensitivity. This circuit was brought to the attention of Hazeltine Corporation who subsequently sued on August 20, 1926

on the basis that their reviews had neutralization by coupling in open space. A judgment was rendered in favor of Hazeltine and appealed by Atwater Kent. After a long drawn out process final settrement was reached with Atwater Kent taking out a license in February 19, 1934 and paying Hazeltine $680,000 in cash. According to

Harold Wheeler, former chairman of Hazeltine, the Atwater Kent case yielded mainly a cash settlement which was a small fraction of the royalties they had escaped. The Duke also assigned to Atwater Kent patent number 1,983,047 which was the same as his previous patent but with inclusion of biasing of the grid with respect to the cathode as modification. Also on July 25,1924, he applied for a patent (no. 1,966,805) to provide for shunt resistances and capacitances across the grid circuits in parallel to the grid tuned circuits. This invention apparently provided no monetary benefits for Atwater Kent. Another discovery during his employ at Atwater Kent which had a significant impact on the reproduction of sound was No. 1,671,105 filed June 23, 1927 and applied jointly by C. L. Farrand, Ernest Ross and Albert D. Silva. It was an armature with a moveable arm which, when connected to a cone, provided a better sound than did horn speakers. In essence it was a basic patent. As far as relatives can determine, he was still employed by Atwater Kent at the date of filing. The question is why

was C. L. Farrand's name on the application. Was it so, that Atwater Kent could use this patent in his own cone speakers royalty free? Or was Silva doing consulting work with C. L. Farrand. With the invention of AC current supplies and with the advent of the electrodynamic speaker, there were questions about its employment in the receiver itself. The Duke carne up with a unique approach to utilize the inductance of the field in combination with a resistance in the negative side of the power supply to energize the

field of the speaker and to provide bias voltage for the grids of the output tubes. His application for Patent Number 1,828,688 was filed on May 10, 1929. Atwater Kent used this system but later many put the field in the B+ and used a resistance in the negative side to provide bias voltage for the output tubes. The Duke distinguished himself at Atwater Kent and he and Atwater were very good friends as later correspondence would confirm. On June 21,1933 he applied for still another basic patent just about the time manufacturers were warming up to the idea of putting radios into automobiles. One essential part of an automobile was a power supply that could deliver the dc voltages for the tubes from battery power. A. D. Silva invented what is known as a vibrator or mechanical rectifier in his Patent No. 1,960,599. Subsequently it was used in Atwater Kent auto radios. Trouble was on the horizon for the "Duke". Atwater Kent had already made a vast fortune in the radio business and organized labor had approached him about

unioni~tion. Faced with stiff competition and shrinking profit margins, Atwater Kent decided to call it quits in 1936. Even though it was reported that Atwater Kent gave his employees six months severance pay, Silva was out of a job. Just about that time Noblitt . Sparks commonly known as Arvin was looking for an engineer to replace a person who was a mechanical engineer acting as an electrical engineer. At the time of his employment with Atwater Kent Silva was making $30,000 a year but had to take a pay cut to $6,000 a year at Noblitt Sparks. The "Duke" was instrumental in launching Noblitt Sparks in the home entertainment field. Silva designed a complete line of radios from a two tube "Mighty-Mite" to large consoles. The former really kept Arvin in business particularly in 1938 when the radio industry was in a state of gloom. Hundreds of thousands of the Mighty Mites were sold to jobbers for as little as $4:10 each. Kevin Silva, grandson of Albert D. Silva has the prototype Atwater 810 designed by his grandfather. It was built on a pre-existing chassis blank and contained everything including the output transformers. On the production chassis some parts were relocated and the output transformer was mounted on the back of the speaker. The only patent A. D. Silva applied for while at Noblitt Sparks was 2,166,613 filed October 13, 1936 and consisted of transformers of the type used in coupling adjacent stages. Each winding was made to be adjusted to vary its inductance and thereby tune the associated circuit with respect to the mutual inductance of one coil to the other. A. D. Duke Silva left Noblitt Sparks in 1945 to form the Columbus Process Company also located in Columbus, Indiana. One of the first contracts was to tropicalize equipment for the Signal Corps. They applied an anti-fungal treatment for apparatus destined for the Pacific. As soon as these ran out the Columbus process Company set up its production to make parts for the radio industry. In 1950 they added another 5,000 square feet for a total of 25,000 square feet. Among the products were output transformers, television transformers, power transformers, vibrator transformers, vertical choke transformers and battery charger transformers. All of the output transformers on RCA's 45 rpm record players were from Columbus Process Company. At peak capacity they had 300 employees and were productivity 10,000 transformers a day. Albert D. "Duke" Silva died February 14, 1954.