摘要 |
When changeover switch (26) selects the output of L band filter (23), changeover switch (28) is turned off and mixer (29) is operated as an amplifier such that the oscillation frequency of local oscillator (31) is controlled based on data fed to data terminal (37) and a channel selection can be performed in mixer (32). When changeover switch (26) selects the output of V band filter (25), changeover switch (28) is turned on and a channel selection is performed based on data fed to data terminal (37) in mixer (29). With this arrangement, the need for a tuning filter is eliminated and a broadband tuner not requiring manpower for adjustments can be provided.
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