Voice of America: Palo Alto in California
Voice of America: Palo Alto in California

This is the second in an occasional series on the stories behind shortwave broadcasting stations in the United States and its territories; it is published in cooperation with the National Association of Shortwave Broadcasters. Some stations are gone and almost forgotten, others can be heard today.

That is the story of an important international shortwave station that was on the air during the intense days of the decisive Pacific War. Programming from this station was beamed south to the Pacific and north to Alaska and it was made up of relays from OWI-VOA and also AFRS.

We take a look at the known information, admittedly a little sketchy, about this significant shortwave relay station, and we begin way back nearly 100 years ago.

Federal Telegraph

There was a maritime wireless station established on Ocean Beach in San Francisco near what became the southern end of the Golden Gate Bridge back in the year 1910. During the American involvement in World War I, this Morse Code wireless station was taken over by the Navy for naval communication, and in 1921, it was handed back to Federal Telegraph.

During the following year, another maritime station with updated electronic equipment was erected further south at a new location in the marshy areas of the inner harbor at Palo Alto. At the time, both of these stations were owned by the Federal Telegraph Company, which also owned a wireless equipment factory in the Palo Alto area, and both stations identified on the air in Morse Code as KFS. Over a period of six years, the maritime wireless communication service from the older Ocean Beach station was fully phased out in favor of the newer Palo Alto station.

Soon afterwards, the communication radio station at Palo Alto was sold to the Mackay Wireless & Cable Company, though the station still identified on air as KFS. That was its main call sign, and back in those days, every new channel in the shortwave spectrum was officially allocated a new three letter call sign. In the mid 1930s, most of the channel call signs from Palo Alto Radio were in the KW series, such as KWA, KWB, KWC, etc.

Immediately after Pearl Harbor, rapid moves were made in the United States to increase the number of shortwave transmitters on the air with international radio programming from a dozen up to about three dozen. In fact, on the West Coast at that time, there was only one regular station on the air with international shortwave programming; that was station KGEI, at Belmont, also south of San Francisco. It is true, special programs were broadcast from some of the communication transmitters operated by RCA (Radio Corporation of America) at Bolinas, but the scheduling was only occasional and spasmodic.

Quite quickly, additional shortwave transmitters were installed at various locations in California and brought into service as soon as possible to give international coverage into the Pacific and Asia, as well as to Australia and New Zealand.

Among these new stations back in the early days of the Pacific War were KWID and KWIX at Islais Creek, KRCA and KRCQ at Bolinas, and an additional unit at Belmont, KGEX. In addition, two new broadcasting units were made available at KFS, the Mackay maritime station at Palo Alto, and these identified on air with the four letter broadcast call signs, KROJ and KROU. A third unit, KROZ, was quickly commandeered for the surrender broadcasts in August 1945.


The first of these new transmitters at Palo Alto was KROJ, and according to published information at the time, the transmitter was a 50 kW Press Wireless unit, manufactured in the United States, sent to England, and re-imported back into the United States.

However, another report states that the new KROJ was in reality an RCA unit, already available, that was quickly installed at Palo Alto and pressed into service. Notwithstanding these published reports, experienced radio personnel in the San Francisco area state that they consider the new shortwave service was transmitted from communication units already on the air at the Palo Alto station, and perhaps modified for broadcast usage.

Experienced international radio monitors in Australia and New Zealand who tuned in daily to the many shortwave stations in California during the Pacific War noted the strong signals from station KROJ and estimated the power output to be at 50 kW. The signal strength surely indicated that the power output of this strong new station could not be less than 20 kW, and certainly not at 100 kW.

Without ceremony or prior publicity, transmitter KROJ suddenly appeared on the shortwave bands with a relay of programming from VOA, the Voice of America and AFRS, the Armed Forces Radio Service. The first known monitoring of this new unit was in Australia in June 1943.

Just prior to Pearl Harbor, OWI, the Office of War Information in Washington, established a branch office in San Francisco. The location was 111 Sutter Street, the well known home for NBC around that era. West Coast programming for the VOA-OWI transmitters was produced in the Sutter Street studios, and also in studios established in two hotels on Nob Hill, Fairmont and Mark Hopkins.

The OWI-VOA office in Sutter Street sent me a copy of their official schedule for the California stations, effective Aug. 1, 1945, just a few days before the surrender broadcasts. This schedule included the programming from all of the California shortwave stations that were active in the VOA network at the time. These stations were KROJ and KROU, as well as KGEI and KGEX, KWID and KWIX, KCBA and KCBF, and KNBA/KNBI/KNBX, as well as the new Hawaiian station KRHO. (Over a period of time, we hope to look here at the history of all of the shortwave stations in the United States, including the California stations.)

This VOA schedule shows such familiar programs from the wartime era as “World News,” “Concert Hall,” “Your Marine Corp,” “G. I. Jive” and “Hymns from Home.” Commentaries from major sporting events were also included in their regular programming. This schedule shows only the English language programming, and none of the programming on the air in the foreign languages of Asia and the Pacific.

It is probable that the broadcast call signs for the relay transmitters at Palo Alto were derived from KRO. The call sign KRO had been in use previously with the RCA shortwave communication station at Kahuku on the island of Oahu, Hawaii and it was recycled into use at Palo Alto in early 1943. Hence, from communication KRO was derived the broadcast call signs KROJ, KROU and KROZ.


The intended coverage areas for the transmissions from KROJ were the South Pacific, coastal Asia, New Guinea, Alaska and the Aleutians. Shortwave frequencies were chosen accordingly, to ensure propagation at the required distance and at the time of day in the reception areas.

The signal strength in the target areas was usually very good. In fact, an army officer serving in North Borneo stated on one occasion, as reported in a radio magazine in Australia, that he was hearing the broadcasts from KROJ via a local medium-wave (AM) station. It is probable that this off-air relay from KROJ in San Francisco was heard from an AM medium-wave station located on Labuan Island, North Borneo, that had been captured from the Japanese just a few days earlier.

A sister transmitter, KROU, suddenly appeared on the radio dial in April 1945, equally unheralded and unpublicized. Programming for this unit was also drawn from VOA and AFRS sources and beamed to similar areas as KROJ, north to Alaska and south to the Pacific. The planned scheduling for these two transmitters was announced ahead of time on air, and in radio magazines in the United States and Australia, and it was also sent to listeners in duplicated form.

At the time of the surrender broadcasts from Tokyo Bay in 1945, another Palo Alto transmitter suddenly joined the network, and this was identified as KROZ. This unit was already in service with communication traffic across the Pacific, it was stated, and because of the sudden requirements at the end of the Pacific War, apparently it was hurriedly given another broadcast call sign in the Palo Alto sequence and brought into service. Maybe this call sign with its very brief usage was even unofficial. Who knows?

Programming from KROZ was in parallel with KROJ. Station KROZ was on the air for a few days only, and at the most, just a week or two.

The last known program broadcasts from KROJ and KROU took place around November or December 1945. The war was over, and the two new and very large stations, VOA Delano and VOA Dixon, both in California, were already being phased into service. The temporary units at Palo Alto were no longer needed for broadcast service, and we would guess that they were quietly taken back into the regular communication service from Radio Palo Alto, station KFS.

The total time of on-air service from KROJ/KROU/KROZ was less than 1-1/2 years, and they vanished as they began, unheralded and unannounced.