Administrative Regulations on Radio Waves Article 46

Call signs shall be composed of English letters and Arabic numbers. The first two characters of international call sign series shall be two English letters; one letter and one Arabic number; or one Arabic number followed by one English letter.The composition of call signs shall adhere to the following rules. Combinations that can potentially be confused with distress signals or signals of the same nature, or combinations that leave radio communications messages shall not be used:1. Land and fixed stations: the first two characters shall be followed by one letter, or the first two characters shall be followed by one letter and then no more than three digits. Fixed communications shall, in principle, have two characters followed by one letter and then two digits.2. Ship stations: the first two characters shall be followed by two letters; the first two characters shall be followed by two letters and then one digit; the first two characters (should the second character be a letter) shall be followed by four digits; or the first two characters shall be followed by one letter and then four digits.3. Aircraft stations: the first two letters shall be followed by three letters.4. Ship survival craft stations: the call sign of carrier ship shall end with two digits.5. Emergency position-indicating radio beacon stations: shall use the Morse letter B or call sign of the carrier ship, on which the radio beacon station is located.6. Aircraft rescue stations: the full call sign of mother aircraft followed by one digit.7. Land mobile stations: the first two characters (should the second character be a letter) followed by four digits, or the first two characters followed by one or two letters and then four digits8. Test stations:a. One character (B, F, G, I, K, M, N, R or W) followed by one digit (except 0 and 1) and then a series of no more than four characters, where the last character must be a letter; or two characters followed by one digit (except 0 and 1) and then a series of no more than four characters, where the last character must be a letter.b. In special cases, the competent authority may, for the purpose of temporary use, provide a call sign of less than four digits in according to the preceding item.9. Space service stations: the first two characters followed by two or three digits.The first digit following the letter as prescribed in the preceding paragraphs shall not include 0 and 1.
中文原文 電波監理業務管理辦法第46條
呼號應由英文字母及阿拉伯數字組成。
國際序列內之呼號,其首二字元應為二個英文字母、一個英文字母加一個阿拉伯數字或一個阿拉伯數字加一個英文字母。
呼號之組成依下列各款之規定,且不得使用易與遇險信號或同性質之其他信號相混淆之組合,或留供無線電通信簡語之組合:
一、陸地與固定電臺:首二字元後再加一字母,或首二字元加一字母後再加不超過三個數字。
固定通信以採用首二字元加一字母加二個數字之組合為原則。
二、船舶電臺:首二字元加二個字母,或首二字元加二個字母再加一個數字,或二個字元(第二字元為字母者)加四個數字,或首二字元加一字母再加四個數字。
三、航空器電臺:首二字元加三個字母。
四、船舶營救器電臺:用母船呼號加二個數字。
五、緊急指位無線電示標電臺:用無線電示標之母船之摩氏字母B、呼號。
六、航空器營救電臺:用母機完整呼號再加一數字。
七、陸地行動電臺:首二字元(假設第二字為一字母)再加四個數字,或首二字元加一個或二個字母再加四個數字。
八、試驗電臺:
(一)一字元(提供之字元為B、F、G、I、K、M、N、R或W加一數字(0與1除外),加一組不超過四個字元,其最後之字元必須為字母者。
或二個字元加一數字(0與1除外),加一組不超過四個字元,其最後字元必須為字母者。
(二)在一特殊情況下,為暫時使用之目的,主管機關得依據前目授予一不超過四個字元之呼號。
九、太空業務電臺:首二字元加二個或三個數字。
前項各款所指字母後之第一個數字不包括0與1。

English translation for reference only; the Chinese text prevails. Not legal advice.