| 摘要 |
PURPOSE:To measure easily an image and an audio intermediate frequencies through simple consitituton by selecting a signal among plural frequency signals corresponding to plural intermediate frequency values, and counting an electronic tuner output and a frequency conversion output. CONSTITUTION:A signal of the image intermediate frequency of an OIRT country, e.g. Germany, England - plus 5,000kHz is outputted from oscillation parts 21a-21g which generate oscillation outputs of frequencies corresponding to image intermediate frequencies of respective OIRT countries with the control signal of a selector 20. The country selected with a select button 19 is displayed on display elements 22a-22g. The intermediate frequency from a tuner part 2, on the other hand, is supplied to a frequency converter 25 through a preamplifier 24 and frequency-converted with a signal from a local oscillator 21. This frequency conversion output is supplied to a low-pass filter 26 to extract only a signal of 5.000kHz frequency, which is passed through a limiter 27 and counted by a frequency counter 17, thereby displaying the frequency of a count display device 23.
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