Published:2009/7/10 22:19:00 Author:May | From:SeekIC
Uses 3.579545-MHz crystal osdllator to drive string of CMOS buffers forming digital delay line. Output delays caused by propagation times in each buffer can be used directly or can be trimmed to specific colors by varying supply voltage. Reference phase and delayed color outputs go to 1-of-8 data selector whose output is determined by code presented digitally to its three color select Iines. Selector drive Iogic must retum to 000 (reference phase) immediately before, during, and for at least several microseconds after each.horizontal sync pulse so set can lock and hold on reference color burst. Sine-wave output chrominance signal is cut down to about one-fourth of maximum video white level.-D. Lancaster, TV Typewriter Cookbook, Howard W Sams, Indianapolis, IN, 1976, p 205-206.
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