| 摘要 |
The bitclocks generating circuit in the receiver of TELETEXT generates the sampling bitclocks to sample a character signal without error by using CRI signal which is contained in compound signal. This generating circuit is composed of a demodulator (10), letter signal processor (20) and display (30). As one phase can be selected out of either 28MHz, 28MHz by CRI signal or five phases by the setting of an initial value of counter (56), the most appropriate phase is obtained out of ten phases. Hence, accurate bitclocks can be generated by fixed crystal frequency.
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