Thursday, September 03, 2026

Royal Beginnings of Radio in Thailand

 
Temples of Thailand

Thank you to Ray Robinson and Jeff White for sharing the episode on Thailand from August 30, 2026.

Jeff: One of the countries in Southeast Asia that is still very active on medium wave is Thailand, and this week, Ray Robinson takes a look back at the royal beginnings of radio in that country.

Ray:  Thanks, Jeff.  The Kingdom of Thailand, formerly known as Siam, shares borders with Myanmar to the west, with Laos to the north and east, with Cambodia to the southeast, and in the extreme south on the Malay Peninsula, with Malaysia.  The current population is around 68 million, of whom 93% are Buddhist, 5% Muslim, and only 1% Christian.  The capital and largest city is Bangkok, which over 11 million people now call home.

During the era of Western imperialism, Siam remained the only country in Southeast Asia to avoid colonisation by European powers.  As an absolute monarchy, Siam joined World War I on the side of the Allies, but in 1932 there was a revolution which resulted in the transition to a parliamentary constitutional monarchy, and the renaming of the country to Thailand.

During World War II, a military dictatorship took over and allied Thailand with the Empire of Japan as part of the Axis powers, but during the Cold War that followed, Thailand became a key ally of the United States and played a major role in countering communism in both the Korean War and the Vietnam War.

Prince Purachatra
Radio broadcasting was introduced to Thailand in 1927 by Prince Purachatra Jayakara, a son of King Rama V.  He was a keen radio experimenter, and, convinced of radio’s potential, he instructed the Post and Telegraph Department to set up an experimental broadcasting service.  Initially, they used a shortwave frequency around 37 metres, with the first test broadcasts being aired in English and French on May 31, 1928, using the call sign HS4PJ, with the ‘PJ’ honoring the Prince, Purachatra Jayakara.  Later, the operating frequency was adjusted to 29.5 metres, and the transmitter was upgraded to 500 watts.



The official inauguration of the public radio broadcasting service took place on February 25, 1930, the Coronation Day of King Rama VII, with the transmission of his speech from the Grand Palace.

At that time, the station had the use of five rooms in the palace, consisting of two small studios where Buddhist sermons were also presented, a larger studio for musical performances (accommodating up to 40 people), a control room, and a reception room.  An antenna was set up on a pole in an adjacent field.

Phyathai Palace – Original Location of Radio Bangkok

In 1932, the station was relocated to the Post and Telegraph Department, and in addition to using the callsign, it began identifying as ‘Radio Bangkok’.  However, the results on shortwave were unsatisfactory for what they were trying to achieve, probably due to the skip zone, so on July 1, 1936 they moved to medium wave, 320 metres, 937 kHz, using a 1kW transmitter, and the callsign was changed to HS2PJ.

On January 1, 1941, Radio Bangkok was renamed the National Radio Broadcasting Service of Thailand, or, Radio Thailand.  After the 2nd World War, the radio broadcasting facilities were steadily improved.  On September 11, 1951, a 10 kW transmitter was inaugurated, with a 250-watt FM studio-to-transmitter link.  This was the first FM broadcast in Thailand.  Broadcasting was not yet an all-day affair, though.  In the 1950’s and early 60’s, Radio Thailand was only on the air from 6-8am and 6-9pm, with news, documentaries, classical and modern Thai music, and radio dramas.  Here’s an audio clip of a close-down message from 1964:

Audio Clip 1 - 1964 - Radio Thailand Overseas Service, Bangkok (11910kHz) – closedown, available as the podcast link at https://www.podomatic.com/podcasts/wavescan


On December 6, 1965, the transmitter was upgraded to 100 kW, and in 1971, a major new Program Production Center was opened, enabling full-time broadcasting.  Then on May 3, 1982, a new transmitter site with a 1 MW transmitter on 1575 kHz medium wave was inaugurated by Crown Prince Maha Vajiralongkorn, who actually switched it on himself.

In 1986, Radio Thailand moved to new headquarters once again, this time providing facilities for all of the then five networks of Radio Thailand – two national services for Thai people, one regional service, one foreign language service for foreign audience in the country and in neighboring countries, and an overseas service for both foreign audiences and Thai expats outside the country.

In 1989, commercial broadcasts in English were introduced, and here’s a recording of a newscast on shortwave with two commercials, for Bangkok Airways and for the Taiwanese airline EVA Air.

Audio Clip 2 - R Thailand World Service (17640kHz) - News, commercials at: https://www.podomatic.com/podcasts/wavescan

Early in 1985, the Voice of America expressed interest in establishing a shortwave relay station in Thailand to boost the capacity of its services to Asia and the Pacific.  It was agreed that the station would be located in Udon Thani province in the northeast of the country, and that the facility would be shared jointly by the VoA and Radio Thailand for its overseas service.  The United States agreed to finance the construction of the station, and the transmitter hall looks not unlike an updated version of the VoA station at Greenville, North Carolina.  Inside the building are seven 500 kW transmitters, which have been operational since 1994.  On inauguration day, the facility was ceremoniously sold back to Thailand for 1 Thai Baht.


The Voice of America was the primary operator and coordinated the use of all frequencies by both organizations.  But the VoA shared the transmitters equally with Radio Thailand World Service, which broadcast in English, French, German and nine regional Southeast Asian languages.  This was the sign-off after a broadcast to West Coast North America:

Classic QSL card from Radio Thailand

Audio Clip 3 - R Thailand World Service 918 kHz (Udon Thani) - end of English available at: https://www.podomatic.com/podcasts/wavescan

And here’s an audio clip from 2019, when at the start of the newscast, they mistakenly ran the news outro sweeper rather than the news intro!
 Audio Clip 4 - 2019 12 01 - R Thailand World Service, Udon Thani (918kHz) - Intro available at: 

However, the extent of Thailand’s international broadcasts has been steadily reduced in the 2020’s, and the last time it was listed at all in the World Radio TV Handbook was in the 2025 edition.  As far as I can see, the Radio Thailand World Service now operates only on the high-power medium-wave transmitter and online.

But, the country is still very active on medium wave.  The current edition of the WRTH lists some 127 medium wave stations around the country, most with 5, 10, 20 or 25 kW, but there is one 50 kW unit, three 100 kW units (on 549, 621 & 1467 kHz), one 400 kW unit (on 891 kHz), and the aforementioned 1 MW station on 1575 kHz) used by the Radio Thailand World Service and the VoA, so there are still some potentially good logging opportunities.  And then there are the usual plethora of stations on FM, including both the government networks and hundreds of private stations, plus ‘special’ stations of the Royal Thai Air Force, the Royal Thai Army, the Royal Thai Police and the Royal Thai Border Patrol.



(Temples of Thailand photo via Vecteezy)