Strange problem with a colour tv I have here. A very loud 50Hz-ish sounding buzzing noise has been causing severe interference to low freqs, LW MW radio and conventional telephone which I traced its source back to the TV. Noise only appears when set is connected to aerial/scart which acts as a radiating aerial. TV works perfectly, but with a 'scope looking at both the inner and outer of the coax socket, there appears a significant waveform. It doesn't alter with picture changes so I presume it's not line timebase. Any ideas? It's a Grundig T70-1020.
Richard UK