Developed for DC Audiovisuel by an electronics engineer specialist in RF, the A.I.R ("Analyseur d'Interférences Radio") is very user friendly. The first tests in the field have just started.
The purpose of this device is to take measurements on the shooting set in order to visualize the presence of perturbing frequencies like the Digital TV ones and to estimate their proximity with the useful frequencies.
First, we carry out, at DCA, the memorizing of the radio mikes which have been rented for the film. This saving is carried out with the transmitters on, mike connected, one radio mike after another. Once this process is completed, the useful frequencies of the radio mikes are stored in a non-volatile EEPROM.
The whole set of memorized frequencies can be displayed on the large LCD screen with a touchkey. Another key makes it possible to visualize, on the X-coordinate of a graphic, the dotted lines of these frequencies. The A.I.R is then ready to be used on the set.
When the sound mixer arrives on the shooting place, he can immediately check, on the LCD display of the A.I.R., if the selected frequencies are clear of any disturbance, without even powering on his radio mikes.
- ZC=OK : RF is not likely to be disturbed
- ZC=KO : RF is likely to be disturbed
Of course it is advised to walk around the set and to remake measurements several times in order to check for the presence of disturbing frequencies. As a matter of fact, the A.I.R makes sequential control of the 470-870 MHz band several times per second, so new disturbances can suddenly appear.
There is one general band screen from 470 to 870 MHz and seven more detailed ones, with steps of 200, 100 or 50 MHz, for more precise informations.
A Clear Zone key makes it possible to display the frequency bands in which the power of pollution is low enough not to be of any disturbing influence for the proper use of radio mikes.
Thus, thanks to the indications provided by the A.I.R, the sound mixer can get in touch with our rental office in order to replace a disturbed radio mike, and to precisely tell us the potential clear zones of his shooting place.
In conclusion this device will become an essential tool for radio mike users in an environment which alas becomes more and more polluted by the increasing number of transmitters operating on the 470 - 870 MHz band.