Measurement of the Immunity of TV-Receivers to AM, RF-Fields in the 3 to 30 MHZ Range, Including the Influence of Connected Cables

The first part of this paper describes an immunity test method and results applied to 10 colour TV-sets (PAL, B/G, with coax input) in the frequency range of 3 to 30 MHz. The method is called "integral test method", because TV-sets as well as cables are exposed to the interference field, simulating real situations. A simple RFI suppression technique is also tested. The second part describes a "synthetic test method" which is simple to realize. Prom results of four different test methods applied to three TV-sets we conclude that the immunity of a TV-set is proportional to the open circuit voltage of an interference source, having 150 Ω internal impedance, whereby the interference source drives currents through the chassis. The interference power from this source is to be applied to the antenna cable shield and to the mains respectively. Results from the synthetic method are in good agreement with those from the integral method. On the other hand the irradiation of the TV-set only (in a stripline) or the injection of an interference voltage at the antenna input do not reproduce the worst interference conditions of a real situation.