N'ọnwa Machị afọ 1941, kọmitii ahụ wepụtara ụkpụrụ teknụzụ maka telivishọn ojii na nke ọcha nke wuru na nkwanye nke 1936 nke ndị Radio Manufacturers Association (RMA) mere. Ọganihu teknụzụ nke usoro akụkụ nke akụkụ ahụ kwere ka ohere iji bulie mkpebi oyiyi. NTSC họrọ 525 akara nyocha dị ka nkwekọrịta n'etiti ọkọlọtọ RCA nke 441-scan (nke RCA's NBC TV network na-eji) na Philco na DuMont chọrọ ịbawanye ọnụ ọgụgụ nke akara nyocha na 605 na 800. A tụrụ aro ọkọlọtọ nke 30 okpokolo agba (ihe oyiyi) kwa nke abụọ, nke nwere mpaghara abụọ na-agbanwe agbanwe na mpaghara 262.5 kwa nke abụọ. Ajụjụ: Gịnị ka a na-atụ aro maka oge ụda na oge ọdịdị ọhụrụ maka oge ụda?
ugboro ole modulation (FM)