发明名称 |
TELEVISION RECEIVER FOR TUNING A SIGNAL INCLUDING A PILOT SIGNAL |
摘要 |
A synchronous demodulator is controlled by a phase locked loop for tuning to a pilot in a television signal. A start-up interval is commenced upon initiation of tuning (either after power-up or a channel change) during which a substitute signal at the pilot frequency is supplied to the phase locked loop to rapidly bring the VCO close to its lock-up frequency. Thereafter the IF signal is supplied. The start-up interval is defined by an AFC Defeat signal from a microprocessor and controls an IF switch. The substitute signal is from a crystal oscillator. |
申请公布号 |
CA2296861(A1) |
申请公布日期 |
1995.07.06 |
申请号 |
CA19942296861 |
申请日期 |
1994.12.15 |
申请人 |
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发明人 |
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分类号 |
H03D1/22;H03D3/00;H03G3/20;H03J7/02;H03L7/10;H04L27/02;H04N5/44;H04N5/455;H04N5/50;H04N21/2383;H04N21/438 |
主分类号 |
H03D1/22 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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