	home shopping hsn to purchase tv station home shopping network inc said its silver king broadcasting co inc unit entered a definitive contract to buy the broadcasting assets of tv station kwvt channel in the portland salem ore area for undisclosed terms additionally the company said kwvt which serves homes began broadcasting home shopping network full time this morning under an affiliation agreement home shopping also said it entered a definitive contract to buy tv station kpst channel in san francisco and kltj channel in dallas reuter 
