An experiment with an audio recording of the reception of a broadcasting radio station in the medium wave band was carried out in order to once again confirm the ability of the anti-noise ferrite rod antenna “Olusha-10” to suppress industrial and domestic radio interference. The principle of operation of the “Olusha-10” antenna is described in detail in the author’s article “Suppression of Common-mode Interference to Radio Reception”.
The essence of the experiment was to compare the sound quality of the same radio transmission from a powerful broadcasting radio station, received by two radio receivers of the same type, one of which received the radio station signal to the built-in standard ferrite rod antenna, and the other was connected to the anti-noise ferrite rod antenna “Olusha-10” instead of the standard one.
The photo below illustrates how the experiment was carried out. In the experiment, two DEGEN DE1103 radio receivers were used, one of which was modified in such a way that, when operating in the medium wave band, the signal to the input of the radio frequency path was supplied not from the built-in ferrite antenna, but from the socket for connecting an external antenna. It was to this socket that the “Olusha-10” anti-noise ferrite rod antenna was connected. Both radios were tuned to a frequency of 1089 kHz, on which the “Voice of Russia” radio station operated. All other radio receivers controls were also set to the same position. The audio signal from the line output of each of the radio receivers was fed in turn to the input of the sound card built into the computer. Audio recording was carried out using the ScanRec ver.1.8.1 program.
The audio recording of the “Voice of Russia” radio program was made on March 11, 2011, from 19:59:32 to 20:03:33 MSK. During the first minute of recording, a radio receiver was connected to the computer’s sound card, which received the radio station signal to the built-in ferrite antenna. Then, during the next minute – a modified DEGEN DE1103 radio receiver with the “Olusha-10” antenna connected to it. Then again a minute was recorded from the first radio receiver, and again a minute – from the second. The difference in sound quality is clearly audible – when recording from the line output of the receiver with the “Olusha-10” anti-noise ferrite rod antenna connected to it, there is practically no noticeable interference, the reception is clear.
Copyright © Sergii Zadorozhnyi, 2011