| 摘要 |
FIELD: frequency-selective facilities employed in communication, measurement technology, automatics and telemechanics. SUBSTANCE: frequency selector includes frequency-to-voltage converter 1, voltage-to-current converter 2, amplifier 3 with controlled element connected in series. Inputs of amplifier 3 and frequency-to-voltage converter 1 are simultaneously input of frequency selector. Bipolar transistor which emitter is connected to output of voltage-to-current converter 2 functions as controlled element. Bipolar transistor sets maximal gain factor only with certain value of current of emitter so that amplitude-frequency characteristic of frequency selector is similar to amplitude-frequency characteristic of narrow-band band-pass filter and amplitude-frequency characteristic is altered by way of change of conversion characteristics of frequency-to-voltage converter 1 and voltage-to-current converter 2. EFFECT: increased functional potential of frequency selector by way of control over form of its amplitude-frequency characteristic. 1 dwg
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