HC Deb 27 November 1980 vol 994 c140W
Mr. Shersby

asked the Secretary of State for the Home Department what estimate he has made of the cost of filtering interference to television transmissions if open channel were to be introduced in a frequency below 900 MHz.

Mr. Raison

Filtering would be either ineffective or impracticable as a means of preventing interference to television reception from open channel transmissions in certain frequency bands below 928 MHz. In cases where filtering would be effective the cost would depend on a variety of factors.