| 摘要 |
PROBLEM TO BE SOLVED: To provide a receiver which can receive both standard and highly fine TV signals. SOLUTION: A 3rd mixer 22 converts an NTSC signal into an IF signal, and an NTSC signal IF filter separates a selected channel from the IF signal in a single superheterodyne system. Meanwhile, a 1st mixer 10 converts a high- definition TV signal into a 1st IF signal of 10 GHz or higher, a 2nd mixer 13 converts the 1st IF signal into a 2nd IF signal having a frequency band equal to the IF signal of the NTSC signal, and a high-definition TV signal IF filter 15 serving as an SAW filter separates a selected channel from the 2nd IF signal in a double-superheterodyne system. Then an IF filter 11, to which the 1st IF signal is supplied from the mixer 10, uses a band pass filter having the in-band flatness and low group delay deviation.
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