video pattern generator

video pattern generator Focussing by eye is possibly accept- able with a B/W set but the resultant pattern will be an egg-shaped "circle". This haphazard method of tuning is totally out of the question with a colour TV set and a pattern generator is essential in this case. IC manufacturers Ferranti saw the need for such a device and have introduced a complete video pat- tern generator on a single chip. When combined in a circuit with a few external components this IC delivers an excellent synchron- ization signal (CCIR standard) and five possible patterns. With S2 included in the circuit there are actually seven patterns availiable. The trick in getting an extra two patterns is quite simple. Considering that "no pattern is also a pattern", white (switch pos- ition A) and black (G) are also possible. The other patterns are (with switch positions of S2 shown in parentheses): vertical lines (B), dots (Cl, crosshatch (D), horizontal lines (E) and degrees of grey (F). The breadth of th...