特点： ·准确的回程损耗/SWR测量 ·可的测试传输线和天线 ·免受现场RF干扰 ·距离错误窗口显示功能（S120A，S251A/B） ·损耗/收益存放（S114B，S332B） ·可选瓦特计 ·可选内置T型连接器（S251A/B） ·合成器到75ppm 技术指标 Model S331A Frequency range 25 to 3300MHz(S331A) 25 to 4000MHz(S400A) Freqeuncy accuracy(CW mode) 75ppm Frequency resolution 100kHz Immunity to interfering RF signals up to^*2 -15dBm Return loss SWR Resolution:0.1dB (S120A,S251A) S810A,S818A,S820A) Return loss:0 to 54dB SWR:1 to 65 Horizontal range:0 to 128*(resolution) Horizontal resolution,rectangular widowing resolution(meter): Coax:(105*10^8)(up)/△ frequency^*3 Waveguide:(1.5*10^8)(√(1-(F F1)^2/√ frequency)^*4 monitor,Option 5) Detector range:-50 to +20dBm,10nW to 100mW Resolution:0.1dB,0.1*W Trace memory 40(S331A and S400A) 50(S120A and S251A) 70(S800A series) 50(S120A and S251A) 70(S800A series)^*5 4(S120A and S251A) 6 (S800A series) RF power detector:+20dBm,50Ω Temperature Storage:-20℃to 75℃ Weight 1.36kg(3.0lbs.)nom(S120A,S251A and S800A series) Size General RS232:9-pin D-sub,three wire serial
