ANNIVERSARY OF KDKA.

New Zealand Herald, Volume LXVII, Issue 20760, 31 December 1930, Page 4

ANNIVERSARY OF KDKA.

DECADE OF BROADCASTING

GIANT NEW STATION OPENED

The, 10th anniversary of station KDKA, Pittsburgh, was observed last, month, when a. special programme arranged by the Pittsburgh Chamber of Commerce was broadcast, from I\DKA and its short-wave station WBXK. Since the elect,on of Mr. Warren G. Harding as president, of the United States was broadcast, on November 2, 1920, this pioneer station has not missed a single day of broadcasting. _ The first, decade of broadcasting in the United States—and probably in the world —was also marked by the opening ot the proposed 400,000 watt, KDKA transmitter at Saxonburg, 30 miles from the station s studios at Pittsburgh. The present, power of the station is 50,000 watts. Incidental to the standing of the station in In© States, the name of the highway passing the new transmitter has been changed from the Saxonburg Road to KDKA Boulevard. ' A 601b. tube, 6ft. in height, and with » diameter of Bin.. which is cooled by means of a, water jacket, is used at, the transmitter. The power consumed by the tube would operate simultaneously 400 electric heaters, while the consumption is equivalent to the electrical energy required to light 1000 average five or sixroomed houses. Enough power to meet the lighting needs of a city of 25,000 inhabitants is generated by the sub-station of the new transmitter. The power is required to operate the new station a.t maximum strength between one and six o'clock in the morning, the hours at which the transmitter will be permitted to function at its maximum energy. The increased output will make KDKA by far the most powerful station in the world. Sixty-two rigid tests were made to find a location which would ho adaptable to favourable broadcasting before Saxon burg was definitely selected. Those tests were made to determine the proper altitude with no interference from metal construction, free from trees as to prevent undue interference and ample area, for erection of the necessary structures and antennae. The site at the new transmitter occupies 1.30 ac.-es. The standard wave antenna over which KDKA broadcasts consists of a circular arrangement, of poles surrounding about eight, acres. The poles are 100 ft. above the ground and painted, according to law, black and yellov.. Aerial hazard beacons also have been erected to serve as a. warning to aviators. A much smaller space if* required tor the short-wave transmitter of WBXK. An intricate system of control governs the manner in which the sta.tion is opeiated. The transmitter is connected to the power lines in the most complete manner yet, developed by electrical engineers. As a programme comes in' n 'ho Saxonburg station by wire it, pasree through an elaborate control panel and an attendant in a glass enclosed booth regulates the volume for satisfactory broadcasting.