A TV receiver having a single vertical sync counter is combined with various gates and a latch circuit to provide two modes of operation. In the first mode of operation, the vertical counter counts up to a first predetermined number of pulses at which time the counter is automatically reset. In the second mode of operation the counter is counted up to a second predetermined number of pulses which is greater than the number of pulses in the first mode before automatically resetting. The two modes of operation enable the TV receiver to readily operate in TV systems having different number of lines per picture.
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