Input change-over type amplifier and frequency change-over type oscillator using the same

Abstract

An input change-over amplifier is capable of effecting a change-over in outputting two signals having different frequencies, without lowering the signal levels thereof. Two signals having different frequencies are fed into two input terminals of an amplifying element. When a signal is input through one input terminal, the other input terminal is grounded. When a signal is input through the other input terminal, the above one input terminal is grounded. In this way, it is possible to effect a change-over in outputting two signals having different frequencies, without lowering the signal levels thereof. Further, since two signals can be fed into an amplifying element through different paths, it is not necessary to provide a matching circuit at a connection point of signal paths. Therefore, the number of required electronic parts can be reduced, an oscillator which is compact in size can be manufactured, and a necessary circuit can be designed within only a short time.

Dependencies are inferred from the claim text.