Indianapolis Times, Volume 36, Number 254, Indianapolis, Marion County, 5 March 1925 — Page 17

ENGINEER HAS SOLUTION TO WAVEPROBLEM Would Divide Broadcasters Into Four Classes. Bv NEA Service PITTSBURGH, Pa., March 5.—S. M. Kintner, research engineer of the Westinghouse Company, has the solution to the problem of assigning wavelengths. This has been stumping the Department of Commerce in its efforts to give every broadcasting station an equal opportunity to broadcast. Kintner’s idea is to divide broadcasters into four classes, and instead of separating all by an arbitrary allowance of 10 kilocycles, as the Commerce Department has tried to do, he would give the super-power broad-casters a large allowance of 20 kilocycles and the rest could be separated by 10. Thus, argues Kintner, there would be less chance of interference among the larger broadcasters or by th<m with the smaller ones. According to Kintner’s table, broadcasters of fronyS to 50 kilowatt power, allowing for higher power in the future, would be in Claas 1, between 300 a.nd 416.6 meters. There would be room for 15 of these large broadcasters, each separated by 20 kilocycles. Class 2 would contain stations down to 500 watts power, between 428.5 and 555 meters, separated by 10 kilocycles. Seventeen channels would be available in this band, but two assignments could be made in the same time area and there could be two time areas, one for the east and another for the west coast. Thus there would be 68 possible assignments in this band. Class 3 would include stations of 100 to 500 watts power, whose influence is mostly local. There would be 45 channels of 10 kilocycles between 205.5 and 294 meters. Three time divisions could be allotted for these, and there could be three assignments of the same Wavelength in each time division, Thu3 640 asignments could be possible In this class. The fourth class would include all Rations below 100 watts power and higher powered stations that would have to await assignment when any of the other classes is tilled. This class could hold an unlimited number of assignments. “Mayday” for SOS International call for distress for aviators using the wireless telephone is “Mayday” instead of SOS. This is the English way of pronouncing the French “m’aider," which means "Help.’*

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Plans to ‘Tell the World’

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NEW RADIO PATENTS

WASHINGTON, March s.—Six patents on radio inventions were granted by the Patent Office during the past week. A brief description of these new patents follows: Carrier Wave Receiving System (No. 1,526,405!), invented by Fred W. Young, of Long Island City, N. Y. The principal object of this invention is to provide a circuit such that demodulators of different kinds may be used without bubstantia! change in the circuit ltaelf. Means for and Method of Limiting Interference in Wireless Signaling (No. 1,526,852), invented by John Hays Hammond Jr., of Gloucester, Mass. Tbe object of this invention is the limiting of the effect of Interference caused by static and other disturbances,encountered in wireless telegraphy, and in the preferred embodiment thereof it depends for Its operation upon characteristics of gaseous or like detectors. Wireless Transmission System (No. 1,526.311), Invented by Max C. Batsel, of Wilklnsburg, Pa. An object of this invention is to provide a system of amplifier circuits, comprising a vacuum-tube generator and an amplifier, with means to couple the amplifier circuit to the radiating system. Mounting for Radio Vacuum Tubes (No. 1,526,353), Invented by Stanley D. Eivingston, of Freeport, N. Y. This invention comprises a combined tube and resistance mounting as a unitary structure, which is adapted to fit on or into a mounting designed for another type of tube. Piezo-Electric Loud Speaker (No. 1,526.319), Invented by Lewis W. Chubb, of Edgewood, Pa. An object of this invention is tc make use of the properties of a piezo-electric crystal for controlling energy in ac-cordance-with telephonic currents. Theostat (No. 1,526,41), invented by James C. Snell, of Oak Park, 111. The object of this Invention is a rheostat for quick or coarse and fine adjustment for corresponding

THE INDIANAPOLIS TIMES

variations in the resistance in the circuit. (Copyright, 1925. by Stevenson Radio Syndicate.) Improve Sockets At last the neglected part behind the pane] seems to be coming in for its proper share of attention. While the perfection of other radio parts has progressed with marvelous rapidity, Improvement in the design of tube sockets has lagged. Only now, apparently, are manufacturers beginning to recognize the vital importance to good reception of comet socket design. Heretofore the socket seems to have been regarded limply as something to hold the tube. But radio engineers every where, tracing many instances of faulty recaption to poorly designed sockets, have turned their attention to this part through which all energy must pass to reach the tube —and the result has been several marked improvements. Modulated Tubes Equipment of the operating station of WHT, the new 5,000-watt broadcaster in the Wrigley Bldg., Chicago, will use modulated tubes submerged In water, according to George E. Carlson, general manager of the Radiophone Broadcasting Corporation, which is building the station, and of which William Hale Thompson is president. Two-hundred-foot towers will support the cage-type aerial. Verplex grounding system will be used. The total distance of power plant from the studios will be thirty-one miles. The plant will be two miles north of Deerfield. Stove-Pipe Antenna Anew radio antenna has been pei-fected by Major Orin E. Marvel, chief engineer of the Dayton Fan and Motor Company, and * forrper signal officer at McCook Field. The antenna is built In the form of a stove-pipe and is easy to errect. Better selectivity and more volume Is claimed for the antenna. Sea-Going Broadcaster Station WTAT of Boston is perhaps the only sea-going land broadcaster in tho country. The equipment was put aboard the Untied States Coast Guard cutter Tampa recently, token 100 miles off the coast and tested for broadcasting efficiency. U. 8. Sends News Press dispatches will continue to be sent by Federal stations from this country to others across the Pacific, because of lack of private commercial broadcasters. Anew bill provides for this until June 30, 1927. Asked what he thought of periodic radio addresses, President Coolidge recently said he did not believe it necessary for the President to address the country periodically as the newspapers are doing this very well. Anew 1,000-watt set has been Installed at 'the Government station, NAA, Arlington, Va., and will start broadcasting just as soon as a suitable wave can be had from the Department of Commerce. Phone Cl rcle 3530 I FIX 'EM RADIO-DOC ' Radio and Electrical Service 711 N. Alabama St Aerial Specialist

Radio Dept. 111, and Wash. St.

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New General Radio Transformer, the best for your set $7.00

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