"Wavescan" is a weekly program for long distance radio hobbyists produced by Dr. Adrian M. Peterson, Coordinator of International Relations for Adventist World Radio. AWR carries the program over many of its stations (including shortwave). Adrian Peterson is a highly regarded DXer and radio historian, and often includes features on radio history in his program. We are reproducing those features below, with Dr. Peterson's permission and assistance.
Wavescan N359, January 10, 2016
The World's Oldest Mediumwave Station: The KDKA Story
The mediumwave radio station KDKA in Pittsburgh, Pennsylvania is frequently honored for its long and illustrious history, beginning when radio was very young and extending continuously over a period of almost a whole century. Its career began hesitantly towards the end of the year 1920, and it is still on the air to this day with its powerful 50 kW signal on 1020 kHz.
This historic American radio station is sometimes regaled as the world's oldest radio broadcasting station, a claim that is often disputed. However, this is not the claim that station KDKA makes for itself, and its own claim as "the world's oldest commercially licensed radio broadcasting station" is completely accurate. The original government license issued to KDKA confirms the accuracy of their statement.
However, in spite of claims and counterclaims laid by several other stations, both within the United States and beyond, it is true without dispute that station KDKA laid a groundwork and forged ahead with their own development in such a way that the history of radio broadcasting can almost be described as pre-KDKA and post-KDKA. The informal inauguration of 8ZZ-KDKA on November 2, 1920 is a pivotal event in the worldwide history of radio broadcasting as a widespread communication medium.
In addition to the international impetus that KDKA gave to mediumwave broadcasting, their influence in the development of shortwave broadcasting is equally evident. However, due to the status and involvement of KDKA as a combined radio broadcasting facility, in our program today, we examine the mediumwave development only of this fortuitous station, before we subsequently penetrate into their shortwave history.
Radio station KDKA began its broadcast service in the evening of Tuesday, November 2, 1920 under a phoned in authorization allowing the temporary usage of the callsign 8ZZ. The entire facility was housed in a quickly assembled wooden hut erected on top of Building K at the Westinghouse factory in East Pittsburgh, Pennsylvania. The newly made 100 watt transmitter radiated on 545 kHz at the low end of what has since become the standard mediumwave broadcast band, and the antenna was a single wire attached to a nearby industrial chimney stack.
The initial election-results broadcast from the new KDKA began at 6:00 pm and even though the results soon confirmed the successful bid for presidency by the Republican candidate, Warren G. Harding, the station remained on air all during that night of stormy weather until midday next day.
From then onwards, KDKA maintained a regular broadcast schedule of music and information, usually during the evening hours. Some ten years later, an article in a radio magazine declared triumphantly: Since its inauguration, station KDKA "has not missed a single day of broadcasting".
The first broadcast studio for KDKA was no more than a microphone with a cable plugged into the transmitter. However, in May of the following year (1921), they experimented with live broadcasts of locally produced music in the factory auditorium in East Pittsburgh.
However, undamped reverberation was a major problem, so they erected a tent on the roof top of the eight story Building K, next to the wooden transmitter shack. This temporary location was in use until a stormy wind blew down the tent, which they then erected indoors in a room at the factory on October 3, 1921.
Give a year later, and KDKA opened studios in the downtown William Penn Hotel at 530 William Penn Place in Pittsburgh. Twelve more years and a new suite of studios was commissioned in the giant skyscraper Grant Building, a 40 story behemoth located at 310 Grant Street in downtown Pittsburgh; this official transfer occurred on their fourteenth anniversary, November 2, 1934.
The KDKA studios remained here for nearly a score of years, and then they transferred to another location at 1 Gateway Center a complex of four skyscrapers constructed on the grounds of several previously demolished buildings. Just five years ago, KDKA moved again, this time to its now current location in Foster Plaza 5 at 651 Holiday Drive, on the western side of the three rivers that flow through Pittsburgh.
During the past almost one hundred years, the major on air studios for KDKA have been installed at five different locations within the Pittsburgh areas. Likewise, the major transmitter facilities for mediumwave KDKA have also been installed at five different locations within the same environment.
The original 100 watt transmitter was installed in the wooden shack on the top of the eight story Building K in the Westinghouse factory complex at East Pittsburgh. The original antenna, a single longwire affixed to a nearby chimney stack, was soon afterwards replaced by a four pole antenna system arranged in the shape of a perfect square.
In July 1924, the KDKA transmitter was installed into a new building, designed in the form of a single storied house, on Greensburg Pike at nearby Forest Hills. A license was granted for KDKA to utilize three different transmitters at that location, with a power rating from 500 watts up to 10 kW. The regular broadcast channel at this stage was 920 kHz.
Half a dozen years later, KDKA was ready to move again, this time to a much larger property at a better location, some 20 miles north of Pittsburgh. A new building on the 120 acre site at Saxonburg contained several transmitters with a total power output of 300 kW; the mediumwave transmitters were installed in the north end of the building and the shortwave transmitters were installed in the south end of the same building.
Approval was granted for KDKA to make a gradual transfer of operations from the old transmitter site at Forest Hills to the new transmitter site at Saxonburg during the latter half of the month of September 1930. It was also at that Saxonburg location that KDKA built their famous superpower transmitter W8XAR which was licensed at 400 kW with approval to transmit experimentally from 1:00 am to 6:00 am on 980 kHz.
Just eight years later again, KDKA was ready for the next move, this time from Saxonburg to Allison Park, just 8-1/2 miles from downtown Pittsburgh. A new transmitter building, designed in the New England Colonial style, was ready for the transfer in early 1940, and the 1937 tower at Saxonburg, standing 718 ft. tall, was dismantled and re-erected at Allison Park.
At this location, a new Westinghouse 50 kW model 50HG was installed; then some 30 years later two 50 kW transmitters made by Gates were installed, and in turn these were replaced more recently by two Harris transmitters at 50 kW each. To this day, KDKA is still on the air at the Allison Park location, with 50 kW now on 1020 kHz, some 3/4 century since this site was brought into service.
We might also add, that half a century ago, KDKA maintained an auxiliary back-up transmitter facility at 4337 Fifth Avenue in downtown Pittsburgh. At the time, the signal from a 5 kW mediumwave transmitter was shunt fed into a tower that was subsequently taken over for use by a new TV station WQED.
Mediumwave radio broadcasting station KDKA has always been a reliable verifier of listener reception reports, and over the years they have responded with a goodly variety of excellent QSL cards.
Next time: We venture into the illustrious KDKA shortwave story.