38. 以無線電話發送警報信號，其中雙音頻變換信號部分，頻率為多少？
(A) 500Hz 與 1100Hz
(B) 2200Hz 與 1300Hz
(C) 2100Hz 與 1300Hz
(D) 2100Hz 與 2200Hz

答案：登入後查看
統計： A(43), B(247), C(99), D(53), E(0) #1312417

詳解 (共 1 筆)

#3216617

依ITU無線電規則(Radio Regulations)第41條第3270款 The radiotelephone alarm signal consists of two substantiallynsinusoidal audio frequency tones transmitted alternately. One tonenshall have a frequency of 2 200 Hz and the other a frequency of 1 300nHz, the duration of each tone being 250 milliseconds. 可得知答案為2200Hz和1300Hz

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