scope:

It describes the conditions and methods of measurement to be used to evaluate the protection afforded in frequency-modulation receivers against impulsive interference, produced by the ignition system of internal combustion engines, or other impulsive interference with a similar repetition rate. The impulsive interference is simulated by a generator giving short pulses with a repetition rate of 100 Hz. The methods of measurement described in this Recommendation apply to interference entering through the normal aerial input circuit and, most particularly, to radio receivers designed for reception of frequency-modulation sound broadcasting in the frequency range between 54 MHz and 108 MHz, and apply both to mains-operated and to battery-operated receivers.