雙語暢銷書《艾倫圖靈傳》第6章:連接兩個世界(9)
They had begun in 1941 with the Vocoder, and tried to adapt it to their purpose by approximating its eleven outputs as being either 'on' or 'off'.
This, however, resulted in a 'badly mutilated' speech signal.
但是這樣產生的語音信號是嚴重殘缺的，無法使用。Accordingly they had abandoned the simple binary 'on or off of the Vernam cipher, and instead approximated the Vocoder outputs not by two possible levels, but by six.
於是，他們放棄了簡單的二進制形式，轉而採用六進制來對聲碼器的輸出進行編碼。
The effect was to encode the speech-signal as a total of twelve streams of 'base six' digits, like 041435243021353....
其效果就是把語音信號編成12串六進制數，比如041435243021353……Each such stream would then be added in modular fashion to a similar but random key sequence, and the result transmitted.
這樣的，然後給它模加註上一串形式相似、但卻是隨機的密鑰，最後再進行傳送。At the other end the identical key would be subtracted, and the speech reconstituted.
接收端收到信號後，減掉一組同樣的密鑰，就可以重新得到語音。The speech signal was to be sampled for its 'levels' fifty times a second, which meant that the transmission was roughly equivalent to sending 300 teleprinter characters a second.
語音信號每秒要採樣50次，這意味着每秒要發送300個字符。They had succeeded in devising the equivalent of a one-time pad system for speech.
他們成功地爲這套語音系統設計了一次性密鑰手冊注。The development was given the intriguing name of 'Project X' or the 'X-system'.
這項新發明，被賦予了一個非常激動人心的名字：X系統。By November 1942 an experimental model had been installed at New York and tested with5 'a synthetic set of signals from a signal generator that had previously been sent to England'.
1942年11月，一臺實驗樣機在紐約部署完畢，並用之前送到英國的信號發生器來產生信號進行測試。In January 1943 they were beginning to assemble the first model intended for operational use.
1943年1月，他們開始裝配第一臺軍用樣機。
