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Column: Wavescan

by Adrian Petersen

CBS on the Air Shortwave from Philadelphia

image of WCAU Tower 1944

WCAU Tower 1944.
© Popular Science Mechanical Encyclopedia March 1944 via

During the radio era before World War 2, there was quite a movement here in the United States, and in other countries throughout the world also, to establish shortwave relay stations in an endeavor to give wider broadcast coverage. At the time, television was a concept and not a reality, and FM radio was still a distant dream. The mediumwave band was not overcrowded though the mediumwave signal generally gave only local coverage. However, shortwave transmissions could give wide area coverage within the country, and even international coverage on a much wider scale.

Many mediumwave stations in the United States established shortwave relay transmitters during the late 1920s and throughout the 1930s to carry their programming to distant listeners. In fact, it is estimated that there have been somewhere around one hundred shortwave stations on the air in the United States during the past eighty years, and probably more than half of these were active during the pre-war era.

One of the shortwave stations that held a high reputation back during the early years was located in Philadelphia, Pennsylvania. This station was launched on behalf of the co-located mediumwave station WCAU under the callsign W3XAU. And again, even though a casual glance would seem to indicate that this was an amateur radio station, this is not the case. Station W3XAU was indeed a professional station, relaying the programming from mediumwave WCAU. The X in a prewar callsign indicated an experimental station, either amateur or professional; and in this case, indeed professional.

The mediumwave station WCAU was launched in 1922 as a very small operation located in the back room of a small radio shop in Philadelphia. Ten years later, following a couple of intermediate migrations, WCAU was installed in a professionally built studio complex, the first building in the United States that was constructed specifically as a radio station. This facility was located at 1622 Chestnut Street in Philadelphia.

Now, at the same time, a new 50 kW mediumwave transmitter was under construction also and this was installed in a new building out at Newtown Square. The initial broadcast from this grand new WCAU was on September 19, 1932.

Before we leave the mediumwave scene and take a look at the shortwave events in Philadelphia, just a touch of humor from the TV series, "Gilligan's Island". On July 5, 1992, Gilligan and his six fellow castaways on a lonely and unidentified tropical island somewhere out in the Pacific tuned in their radio receiver and they heard a broadcast from a radio station that gave the identification announcement, "WCAU". At the time, the real WCAU in Philadelphia had become WOGL, and so there really was no radio station on the air with the callsign WCAU at that stage.
W3XAU QSL 1936

W3XAU Listener Confirmation Card 1936

Not only was there a new suite of studios and offices, and a new transmitter facility back in 1932, but the relatively new medium of shortwave broadcasting was also under development. Early in the year 1930, a small locally made 1 kW shortwave transmitter with the callsign W3XAU was installed with the regular mediumwave unit in Philadelphia. It is claimed that this was the first license issued by the FCC for an international shortwave broadcast station as a commercial operation.

However, two years after the Newtown Square facility was inaugurated, a re-built version of the same 1 kW shortwave transmitter was installed alongside the huge 50 kW mediumwave unit. All of these developments took place during the era when the innovative William Paley of later CBS fame was at the helm.

Four years later, this same transmitter was re-built to 10 kW capacity and two V type antennas were erected for coverage into Europe and South America. Station WCAU became even more ambitious for a truly international outreach with the erection of two large curtain antennas for coverage into the same areas, Europe and South America. At the same time, they made a request to the federal licensing authorities for 50 kW operation on shortwave. In fact, on several occasions in the late 1930s and early 1940s, they made similar applications, but on each occasion the request was denied.

With war clouds developing over Europe in 1939, the FCC took a hard look at the international shortwave scene in the United States and issued three new rules. This edict, issued on May 23, 1939, required that shortwave callsigns should be regularized, power should be increased to 50 kW, and directional antennas should be installed.

As far as callsigns were concerned, this edict gave time for consideration and negotiation regarding desired call letters. Initially, the first new callsign chosen to replace W3XAU was WCAI. This new callsign for the shortwave outlet, WCAI, proved to be only temporary. With information derived from Time magazine, FCC news releases, and several other sources, it is learned that this temporary new callsign was in use for a little less than two weeks beginning in mid August 1939.

The FCC subsequently ruled that all callsign changes for the shortwave stations should become effective on September 1. However, some stations introduced their new callsign prematurely and at least a couple were a little tardy in implementing the change. As far as W3XAU was concerned, the change from the initial WCAI to the subsequent WCAB was implemented on August 26, one week before the official date.

As for the directional antennas, they were already in place. And the power increase to 50 kW? They had already applied on several occasions and been denied. However, there was another mitigating factor involved; CBS had a large new shortwave station under construction at Brentwood on Long Island. Initially, the concept was for WCAB in Philadelphia to supplement the new Brentwood facility. However, in view of the power restriction, it was finally considered best to close the Pennsylvania station in favor of the large new facility under development on Long Island.

Programming from the Philadelphia shortwave station was initially a tandem relay from mediumwave WCAU, though separate identification announcements were given live over the air. However, when the station became a genuine international broadcaster, much of the scheduling was specifically prepared programming for the target areas, Europe & Latin America. Programming in foreign languages was taken on relay from the CBS sister shortwave station W2XE in Wayne New Jersey, and programming in English was also taken live from the CBS national network. This shortwave station was heard quite frequently throughout the Americas, over in Europe, and also in the South Pacific.

The new 50 kW shortwave transmitter WCRC at Brentwood was officially inaugurated on January 1, 1941. Just one year later, the 10 kW W3XAU-WCAI-WCAB at Newtown Square was finally switched off, and this nostalgic event occurred at midnight on December 31 in the same year 1941.

However, that is not the end of the story. The large new international shortwave station at Brentwood was taken into service with OWI-VOA (Office of War Information & Voice of America) programming less than two months later, on February 24, 1942 and the 10 kW unit in Philadelphia was packed up and sent over to England for use by the BBC in London.

How interesting it would be to find out the information from the other side of the Atlantic as to what happened to this famous American transmitter while it was in service over there in islandic Europe.

Read this column with appendices and additional material.

image of Adventist World Radio logo
Adrian Petersen is a noted radio historian and broadcaster for many years with Indianapolis based Adventist World Radio, a global shortwave, AM, FM and satellite radio network. Originally from South Australia, Adrian has worked in radio across Asia and the Pacific and is well known worldwide for his long running Wavescan radio series. He has published an extensive number of radio heritage articles using his large database of historical information, and personally maintains the AWR heritage collection, one of the world's largest privately held memorabilia collections.

Views expressed in this column are those of the author and may not necessarily represent those of the Radio Heritage Foundation. Send us your column comments and feedback.


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