"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, January 13, 2013
100 Years of Wireless & Radio in Bulgaria - Part 2: Early Radio Broadcasting
In our continuing series of topics on the hundred year history of wireless & radio in Bulgaria, we come to the story of early radio broadcasting in this eastern European country. We take this interesting information from all available sources, including Bulgarian sources accessible on the internet, and radio magazines in Europe & the United States, as well as radio magazines in Australia & New Zealand.
The very 1st radio broadcasting event in Bulgaria took place on September 25, 1921. At the time, radio broadcasting in any country was still very young, not much more than a couple of years old at the most. As we assemble the story in Bulgaria, this is what happened.
The radio event was announced in advance. The German radio station at Nauen, out from Berlin, planned the broadcast of a radio program in German & Russian. According to the available information, engineers in Bulgaria modified a Morse Code transmitter in a building near the railway station in Sofia.
They received the broadcast from Germany and fed it into the low power local transmitter in Sofia for rebroadcast. This programming was received best, it is stated, in the Sofia Post Office and also at the telegraph station located at Kyustendil, around 50 miles southwest of Sofia. His Majesty King Boris 3 donned the antiquated headphones of the day at the Sofia location on this historic occasion and heard the radio broadcast from Germany.
Five years later, a radio club was formed in Sofia, and they announced that they planned to obtain a radio transmitter and put it on the air. However, their intended project was never fulfilled. That was in 1926. Then around 3 years later, plans for two separate radio broadcasting stations were implemented somewhat simultaneously.
The 1st of this pair of radio organizations was a group of military technicians at the local military barracks in Sofia. Under the initiative of Georg Vulkov, they built a simple radio transmitter, using 2 Marconi valves at 80 watts each. The transmitting antenna was a regular wire receiving antenna, 160 ft long and 30 ft high. Electric power for this new facility was provided by a generator attached to a petrol motor.
At 9:00 am on Sunday November 24, 1929, this new "Radio Sofia" was launched on 1429 kHz mediumwave, though the operating frequency was changed to 857 kHz soon afterwards. This 1st historic inaugural broadcast was composed of recorded music with occasional announcements.
A few weeks later, on December 13, a somewhat regular programming schedule was introduced with evening broadcasts usually 3 times each week. This era of radio broadcasting in Bulgaria was under the patronage of Professor Assen Zlatarov. As time went by, additional planned programming was presented on air, including agricultural information, Children's Hour, sports and language lessons.
A few months after the 1st station Radio Sofia was launched, a planning meeting was held for the formation of another radio broadcasting station, Rodno Radio, Homeland Radio. That was on March 30, 1930.
Six weeks later, the usage of a building at 3 Benkovski Street was granted to the new Rodno Radio, and they installed their studio and transmission equipment on the 2d floor. The electronic equipment came from the 1st Engineering Battalion of the Bulgarian army.
This new Rodno Radio, the 2nd radio broadcasting station in Sofia, was inaugurated at 6:00 pm on June 15, 1930, also a Sunday. Subsequently, the two hour programming was on the air 2 or 3 times a week, with 2 kW on the longwave channel 105 kHz, and it was heard by listeners living in nearby towns with the use of crystal set receivers.
On June 6 of the following year 1931, the name of Rodno Radio was changed to Radio Sofia, apparently indicating the amalgamation of the 2 different radio stations. At the end of that same year, December 31, His Majesty, Tsar Boris 3, made his first radio broadcast, in honor of New Year's Day.
A new broadcast transmitter for capital city coverage on 1187 kHz was installed at Pavlova during the year 1934; and on January 25 of the following year 1935, the radio broadcasting station was nationalized and taken over by the government, by order of King Boris. Construction work on a new studio building began in 1938 at 4 Dragan Tsankov Boulevard though this facility was not completed for several years.
Regional mediumwave stations were installed at 2 country locations around the middle of the 1930s, and these were:
All 3 of their mediumwave stations were incorporated into a radio broadcasting network on May 21, 1936, with regular relays from the headquarters station in Sofia.
It was on Wednesday, October 13, 1937, that a huge new mediumwave station was officially dedicated at Vakarel, 15 miles south east from Sofia, for nationwide coverage from the one location. Test broadcasts began 6 weeks later, on November 17 with 100 kW on 850 kHz.
At the time of construction, the Blaw-Knox radio tower at 705 feet was the 2nd tallest man made structure in the world, and the tallest in Europe. To this day, it is still the tallest in Bulgaria.
On the next occasion, when we take another look at the radio scene in Bulgaria, we will focus on the early shortwave developments in their country.