Simplify the following text for a Grade 6 native English-speaking person.
Original: BBC1 and ITV soon added their own 625-line services on UHF ( British channels 21 to 69 ) , and PAL color was introduced on UHF only in 1967 â `` 1969 .
Simplified: PAL color was introduced on UHF only in 1967 ( for BBC2 ) and 1969 ( for BBC1 & ITV ) .