PURPOSE: To obtain a wide band PLL control variable oscillator which is capable of obtaining an oscillation output with high stability in a wide band and is capable of being inexpensively composed.
CONSTITUTION: In a wide band PLL control variable oscillator provided with a programmable variable frequency divider frequency-dividing the oscillation output signal of a voltage control oscillator based on the set data of a microprocessor, the voltage control oscillator forms the inductance Lp of an LC resonance circuit by the pattern of a printing wiring board and a diode D1 for band switch is connected between (a) point to be the start end of this pattern and (b) point to be intermediate. This diode D 1 is switched and controlled to an off state when a set frequency is a low band and to an on state when the frequency is a wide band by the control of the microprocessor. As a result, the oscillation condition of an LC oscillation circuit can be optimized over wide bands, and stable and continuous variable oscillation outputs in wide bands can be obtained without generating the extreme lowering or the stoppage of oscillation outputs or the jump of an oscillation frequency.
SUTANI YASUO
HATANAKA OSAMU
