modem tester
A small portable selfcontained device that simulates data communications control functions, evaluates system performance, and isolates equipment failures.It is intended for testing of either asynchronous or synchronous modems in simplex, halfduplex, or fullduplex mode. It determines the overall condition of a data channel consisting of a telephone line with a modem at each end.This type of tester transmits a 511bit pseudorandom test pattern and measures the biterror rate of the received signal.; 一個(gè)小型攜帶式的獨(dú)立裝置,可以模擬數(shù)據(jù)通信控制功能、估價(jià)系統(tǒng)性能以及查找設(shè)備 故障。其目的在于檢測(cè)單工、半雙工或雙工通信方式下的異步或同步調(diào)制解調(diào)器。它用 來(lái)測(cè)定由電話線及其兩端的調(diào)制解調(diào)器組成的數(shù)據(jù)信道的全部情況。這種檢測(cè)器 發(fā)送一個(gè)511位的偽隨機(jī)測(cè)試編碼并測(cè)量接收信號(hào)的誤碼率。