By Harjap Singh Aujla
In the aftermath of Second World War, the British used Himalayan peaks of Simla to monitor shortwave broadcasts originating from their adversary nations. This arrangement worked in independent India too. Our radio broadcast monitoring station worked for a long time in Shimla, it might have folded up by now, because most the nations have ceased their international shortwave services. The shortwave and medium-wave have been replaced by FM.
Harjap Singh Aujla
I did something similar during the summer of 2021. I spent four months of extreme heat and humidity at Shoghi a small suburb located some eight miles short of Shimla on Kalka – Shimla Highway. From this location the plains of Punjab can be seen clearly as far as the eye can see. My technical companion in this period was my German Radio Satellit 700, which is a sensitive receiver. FM coverage is based on the principle of point to point contact above the horizon. Surprisingly I could pick up the signals from all the All India Radio (AIR) FM stations located in Punjab.
The farthest station is AIR Fazilka located more than 250 kilometers from Shoghi and its signal was clear on 100.8 MHz. The second farthest station is the AIR External Service Station Amritsar radiating on 103.6 MHz. As long as it was the only station on the air starting at 5:00 am, its reception was crystal clear. But the moment AIR Shimla goes on the air at 6:00 am, it is effectively blocked by the transmissions of the high altitude station AIR Shimla at 103.7 MHz. The clear range of AIR Shimla is nearly 175 kilometers, which blocks the adjacent frequency of AIR Amritsar up to Dhilwan in Kapurthala district. The designed range of the 300 meter high tower of AIR Amritsar at Gharinda, with 20 kilowatt transmitter power, is 100 kilometers, which can reach the city of Jalandhar, but AIR Shimla does not let it cross Dhilwan. This I have personally experienced while driving between Chandigarh and Amritsar.
The signal of AIR Amritsar is disturbed by another high altitude transmitter of AIR Dharamshala broadcasting on 103.4 MHz. How can three powerful transmitters operating from Dharamshala, Amritsar and Shimla be clustered so closely on 103.4, 103.6 and 103.7 MHz. This is obviously a big technical blunder, which deserves to be corrected immediately by the frequency allocation officials of All India Radio.
AIR Bathinda can be tuned in easily on 101.1 MHz. AIR Patiala 100.2 MHz is very well received at Shoghi. The finest reception is of AIR Chandigarh on 107.2 MHz and AIR Jalandhar on 100.9 MHz. Both are transmitted from the high altitude transmitting tower located at Kasauli. The reception of AIR Ludhiana 100.1 MHz is quite powerful in Shoghi, but at times it is blocked by AIR Patiala operating on the adjoining frequency of 100.2. The range of both AIR Ludhiana and AIR Patiala is 50 kilometers each and overlapping, for optimum utility they also deserve to be separated.
harjapaujla@gmail.com