Superheterodyne receiver of scanning type with indicator means to display received frequency and frequency being stored in memory
AssigneeSanyo Electric Co., Ltd.
InventorEigo Imamura
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AssigneeSanyo Electric Co., Ltd.
InventorEigo Imamura
Estimating the term…
A superheterodyne receiver of a scanning type, comprising a high frequency amplifier, a mixer, a local oscillator, an interdmediate frequency amplifier, a detector, an audio frequency amplifier, a loud speaker, and an automatic scanning/manual scanning selecting switch, said local oscillator comprising a digital frequency synthesizer comprising a voltage controlled oscillator, a programmable frequency divider for dividing the frequency of the output from the voltage controlled oscillator, a reference oscillator, a random access memory for storing the information concerning the rate of the frequency division by the frequency divider, and a phase detector for phase detecting the frequencies of the outputs from the reference oscillator and the frequency divider for providing a control voltage to said voltage controlled oscillator, said receiver further comprising an astable multivibrator for generating pulses for scanning the frequencies of the receiving bands, a counter for counting the pulses from the astable multivibrator, a decoder for decoding the count output from the counter, a plurality of light emitting diodes correspondingly coupled to the decoder output, a plurality of switching transistors connected to a plurality of bit parallel outputs of the random access memory, a plurality of switches for presetting in the random access memory the information concerning the rate of frequency division by the frequency divider corresponding to a predetermined channel, a squelch circuit responsive to a noise detected output obtained when the said detector detects a noise for disabling the audio frequency amplifier, a plurality of undesired channel setteing switches for presetting a channel reception of which is not desired, and a switching transistor responsive to the reception of the frequency corresponding to the channel as set by the said undesired channel setting switch for providing a potential for forcibly enabling the said squelch circuit for disabling the audio frequency amplifier.
A superheterodyne receiver of a scanning type, comprising means for selectively receiving a high frequency signal including a plurality of channels each channel being a different frequency, local oscillator means for providing an oscillation frequency signal the frequency of which is different by a given frequency difference from the frequency of said received high frequency signal, and mixing means responsive to said received high frequency signal and said local oscillation frequency signal for providing an intermediate frequency signal;
Dependencies are inferred from the claim text.