| 摘要 |
PURPOSE:To increase the stability of not only the frequency but the degree of IF shift, by forming a local oscillator and a beat oscillator with different frequency synthesizers and giving an equal shift to the division ratio of a variable divider contained in each of the two oscillators mentioned above. CONSTITUTION:The division ratio set value R for local oscillation synthesizer is fed to a display device 12 and a digital operator 11; and the division ratio set value S for beat oscillation synthesizer is set to a digital operator 15. An IF shift knob is operated to generate a pulse train from a rotary pulse generator 14, and the pulse train is totalized by an up-down counter 13 to produce the digital value DELTAS corresponding to the number of IF shift pulses. The value 8 is applied to the operators 11 and 15, and the output of these operators become S and S+DELTAS each. Accordingly the division ratio becomes equal between the variable dividers incorporated in the frequency synthesizers 50 and 80 respectively. |
