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"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 476, February 15, 2004

The Story of the Indian Chronohertz Station ATA

Several weeks back, our correspondent in India, Jose (his name is not Spanish; it is pronounced as in English, Jose) Jacob provided us with some interesting information about the chronohertz station ATA in New Delhi, and he suggested that we present a Station Profile in Wavescan about this now non-existent station.  OK, Jose, here it is!  Itís the story of the Indian chronohertz station, ATA.     

It was back in the year 1956 that the National Physical Laboratory on the edge of New Delhi in India began to formulate plans for establishing a radio broadcast service for the dissemination of very accurate time signals on a very accurate frequency in the international shortwave bands.  Three years later, on Feruary 4, 1959, this new broadcast service was launched without prior publicity using a 2 kw transmitter on exactly 10 MHz.

This new station was located at Kalkaji, in Greater Kailash on the edge of New Delhi.  The antenna was a horizontal dipole, one wavelength high, directed physically northeast-southwest, giving it an almost circular coverage pattern. 

The frequency 10 MHz is used by many other chronohertz stations in Europe, the United States, the Pacific and Asia, but the lower power of all of these units means that little interference is encountered in the main coverage area of each station.  In 1974, the National Physical Laboratory installed an atomic caesium clock, thus increasing the accuracy of the time signals to an infinite degree.

It was in the following year 1974 that the international radio community in Southern Asia began to focus attention on this station, and as a result of reception reports from many distant listeners, QSL letters were issued by the station director.  One year later again, an 8 kw transmitter was installed at ATA, replacing the original 2 kw unit.

In  November 1976, the National Physical Laboratory conducted a three day convention under the title, "Seminar on Time and Frequency."  Our own DX editor, Dr. Peterson, was invited to present a paper at this convention on "The Usage of Chronohertz Signals by DXers, Shortwave Listeners and International Radio Monitors."  He also designed a new QSL card for them.  At this seminar, they also announced that an additional 8 kw transmitter had just been inaugurated for use on the additional channel 15 MHz.

During the following year, an additional transmitter of the same power was installed at station ATA, and this radiated on 5 MHz.  By this time, the old AWR DX program ìRadio Monitors Internationalî was well established, and so, beginning in 1978, an annual ìATA Dayî was conducted on air, drawing attention to the station and to the availability of their QSL card.

In 1988, the chronohertz signals from ATA were placed onto the INSAT satellite over India, and by this time the transmitters were ailing and at times malfunctioning.  After a long period of consideration, and increasing technical problems, the decision was finally made not to replace the old electronic equipment, but rather to take the station off the air.  Jose states that ATA staff told him in telephone conversations that the radio station was closed somewhere around the year 2000.

Over the more than 40 years of broadcast activity, station ATA in New Delhi had been on the air with a total of four different transmitters on three different channels--5 MHz, 10 MHz and 15 MHz.  Their signal was heard throughout Southern Asia and at times in countries far beyond, and there are just a few distant listeners who are now holding a historic QSL card from station ATA, printed with black text on a yellow card.