| 单词 | PTT |
| 释义 | PTT 1. Post, Telegraph, and Telephone. Referring to the government agencies in many countries that traditionally operated the public postal, telegraph, and telephone services. PTTs were the rule outside the United States, which never owned or operated the telegraph or telephone networks. Most nations later divided the responsibilities for postal, telegraph, and telephone services, and assigned telegraph and telephone services to what generically was known as a telecommunications organization ( TO). More recently, most developed nations have fully or partially privatized telecommunications services. 2. Push-To-Talk or Press-To-Talk. Also known as over-over. In reference to the process used to key a microphone or transmitter to send a message over a half-duplex radio system, such as Citizens Band (CB).The full cycle is push-to-talk and release-to-listen. As the half-duplex radio system will support transmission in only one direction at a time, the parties must negotiate a dynamic protocol that considers the demands of the conversation and the various conversationalists. See also CB Radio Services, key, protocol, and radio. 74570c16.qxd 9/11/07 12:27 PM Page 396 |
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