[Wendymott]

When I was a TV apprentice in the early 60's, our workshop was in Ilkley west yorks. Ilkley had an RF cable system that was basically Band 1. The aerials were sited in a field just below Middleton Hospital.....in the daytime occasionally viewers were bugged by swirling patterns especially on BBC1 CH2 .. this was tracked down to a Diathermy machine use in the Physiotherapy dept. Large power on 50 mhz ish...the only cure was to re site our aerials to a field further north 1 mile away.