VHF波段的DSC移频调制的范围是() ["A.±400MZ","B.±85HZ","C.±40HZ","D.±15HZ"]
氧化钛基反应器设计入口烟温达到()时投入喷氨系统。 ["305℃","320℃","420℃","450℃"]
VHF无线电话的调频指mf越高,则() ["A、抗干扰性强,门限效应小","B、抗干扰性强,门限效应大","C、抗干扰性差,门限效应小","D、抗干扰性差,门限效应大"]
关于VHF通信的特点,不正确的是() ["A、是近距离的通信","B、天线尺寸小","C、接收机中须加静噪电路","D、接收机中须加有AGC电路"]
卸氨操作过程要缓慢进行,保持卸氨压力在()左右(即槽车与储罐间的压差)。 ["0.1MPA","0.2MPA","0.4MPA","压力大小均可"]
三位滑阀中位为H型机能的特点是:系统()卸荷,换向精度(),启动(),()浮动。