YDT 789-2006 免提电话机技术要求和测试方法.doc

YD/T 789-2006 YD Communications Industry Standard of the People’s Republic of China YD/T 789-2006 In place of YD/T 789-1995 Technical Requirements and Measuring Methods of Hands-Free Telephone Sets Issued on December 11, 2006 Implemented on January 1, 2007 Issued by Ministry of Industry and Information Technology of the People’s Republic of ChinaYD/T 789-2006 Contents  TOC \o 1-2 \h \z \u  HYPERLINK \l _Toc422141058 Foreword  PAGEREF _Toc422141058 \h 3  HYPERLINK \l _Toc422141059 1. Scope  PAGEREF _Toc422141059 \h 5  HYPERLINK \l _Toc422141060 2. Normative References  PAGEREF _Toc422141060 \h 5  HYPERLINK \l _Toc422141061 3. Terms, Definitions, Abbreviations and Graphic Symbols  PAGEREF _Toc422141061 \h 5  HYPERLINK \l _Toc422141062 3.1 Terms and Definitions  PAGEREF _Toc422141062 \h 5  HYPERLINK \l _Toc422141063 3.2 Abbreviations  PAGEREF _Toc422141063 \h 7  HYPERLINK \l _Toc422141064 3.3 Graphic Symbols  PAGEREF _Toc422141064 \h 7  HYPERLINK \l _Toc422141065 4. Technical Requirements  PAGEREF _Toc422141065 \h 7  HYPERLINK \l _Toc422141066 4.1 Service Conditions  PAGEREF _Toc422141066 \h 7  HYPERLINK \l _Toc422141067 4.2 Transmission Characteristics of Hands-free Calls  PAGEREF _Toc422141067 \h 8  HYPERLINK \l _Toc422141069 4.3 Direct Current Resistance  PAGEREF _Toc422141069 \h 9  HYPERLINK \l _Toc422141070 4.4 Dialing Characteristics of Telephone Set  PAGEREF _Toc422141070 \h 9  HYPERLINK \l _Toc422141071 4.5 Switching Characteristics of Telephone Set  PAGEREF _Toc422141071 \h 9  HYPERLINK \l _Toc422141072 4.6 Safety Requirements  PAGEREF _Toc422141072 \h 9  HYPERLINK \l _Toc422141073 4.7 Environmental Adaptation of Telephone Set  PAGEREF _Toc422141073 \h 9  HYPERLINK \l _Toc422141074 4.8 Lightning Resistance  PAGEREF _Toc422141074 \h 10  HYPERLINK \l _Toc422141075 4.9 Electromagnetic Compatibility  PAGEREF _Toc422141075 \h 10  HYPERLINK \l