A wireless telegraph corresponding to two transmission frequencies, wherein first frequency is double or around double second frequency, comprising first local oscillator for oscillating a signal of first local frequency; a P-divider for dividing said first local frequency signal by a factor of P; second local oscillator for oscillating a signal of second local frequency; a Q-divider for dividing said second local frequency signal by a factor of Q; first mixer for entering said first and second local frequency signals and outputting a signal of said first frequency; and second mixer for entering said P-divided first local frequency signal and said Q-divided second local frequency signal and outputting said second frequency signal.