"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 N416, February 12, 2017
Puerto Rico on Shortwave: The Early Years
In our program today, we pick up again the story of radio broadcasting on the American island of Puerto Rico, and on this occasion, it is the story of early shortwave radio on this Caribbean Island. It is true, there never has been a regular shortwave radio broadcasting station on Puerto Rico, but nevertheless, shortwave radio has played its part on this island of tropical delights.
Most of the professional shortwave events on Puerto Rico have centered around the activity of RCA, the Radio Corporation of America, or under its local name, the Puerto Rico Radio Corporation. They established the first mediumwave broadcasting station WKAQ in 1922, and soon afterwards, work began on establishing a shortwave communication station in the capital city area, San Juan.
The first test transmissions went on the air in the middle of the year 1925, and these were described as "satisfactory". These transmitter tests were radiated under the callsign WGT, and they were noted in the United States on 13705 kHz and 13780 kHz.
The major purpose for this new shortwave station was to communicate with the continental United States, and the mainland station in this procedure was station WNC, located at Hialeah in Florida. It is apparent that the shortwave transmitters on Puerto Rico were all operating at a lower power rating, probably considerably less than 10 kW.
During the pre-war years, RCA-RCPR in San Juan was logged on shortwave under a plethora of callsigns, and perhaps not all of the in-use calls were noted in the continental mainland. Back in those days, it was the confusing practice to issue a callsign for each shortwave transmitter with also additional callsigns for each shortwave channel is use.
The first block of callsigns for San Juan was in the WG series, including for example: WGT WGU WGX and WGXX. A second block of callsigns was utilized soon afterwards, and these were in the WC series, including: WCT WCU and WCV. A third block of callsigns was noted in the WD series, such as for example WDF.
There were many notable occasions when one of the RCA-RCPR shortwave transmitters was taken into use for the transfer of radio programming from Puerto Rico to the mainland for rebroadcast via the mediumwave networks across the United States. These shortwave program relays containing news, commentaries and island features were produced usually in the studios of the San Juan mediumwave station WKAQ.
There were numerous occasions also, when San Juan's WKAQ received a relay of mainland programming for rebroadcast in Puerto Rico. This was during the era of escalating tensions in continental and islandic Europe, immediately prior to the commencement of World War 2.
The mainland programming was beamed to Puerto Rico from the two CBS 10 kW shortwave stations, W2XE (Wayne, New Jersey) and W3XAU (Philadelphia, Pennsylvania). After the official regularization of experimental American shortwave callsigns on September 1, 1939, these two stations continued to provide a relay of programming for Puerto Rico under the new callsigns WCAB and WCBX.
In addition to the two-way shortwave services in Puerto Rico from RCA-RCPR WKAQ, there was also another similar though somewhat smaller shortwave service provided by another mediumwave station in San Juan. The mediumwave station was the original WNEL, and the shortwave counterpart was allotted the callsign W4XP.
Mediumwave WNEL was inaugurated in San Juan in 1934, some 14 years after the island's first station, WKAQ. At the time of the inauguration of the original WNEL, it was announced that a shortwave outlet would soon be added with the callsign W4XP.
Back then, a comparatively new series of consecutive callsigns was issued by the FCC in Washington, DC in the W4X series. A well-known experimental callsign during that pre-war era was W4XB, which was the shortwave counterpart of the historic mediumwave WIOD on the Isle of Dreams in Miami, Florida.
Shortwave W4XP on Puerto Rico was described as a low power remote experimental transmitter which at times relayed the WNEL mediumwave programming in the 49 metre band for the benefit of country listeners on Puerto Rico.
Mediumwave WNEL in Puerto Rico also received a relay of American radio programming by shortwave, and this was via the two NBC shortwave stations, W3XL and W3XAL at Bound Brook, New Jersey. At the time when the experimental callsigns of American shortwave stations was regularized on September 1, 1939, these two stations became WRCA and WNBI.
In June 1944, station WNEL-W4XP was heard by the noted Rex Gillett in Adelaide, South Australia with news and commentaries on 15130 kHz. This program transfer to the American mainland had to be via one of the RCA-RCPR transmitters, not the little W4XP, which in any case was no longer in use.
Another shortwave station of note in the pre-war era was the communication station operated by Pan American Airways. This station was noted with the callsign WMDU and it was allocated seven shortwave channels for communication with company planes as well as with company land-based stations at other locations.
Now, as was stated above, there never has been a regular shortwave broadcasting station on the island of Puerto Rico. However, and less well known, is the fact that there were indeed at least four major attempts to establish a shortwave broadcasting station on this strategically located island. That's our story on the next occasion when we focus on the radio scene in the Middle Americas.