为了保证调幅无线电稳定地发射、有效地工作以及广播设备的保养,日本广播公司(NHK)正采用全固态发射机来代替普通的、真空管发射机。这种发射机采用场效应晶体管(FET)作为功率放大器。为了适应输出功率等于或大于20kW的大功率发射机的需要,NHK同Tokin两公司联合研制了一种用于高频大功率广播的THE-51静电感应晶体管(SIT)。NHK把这种SIT用于本财政年度制造的20kW AM无线电发射机上,并将用于1989年生产的100kW发射机上。 In order to ensure the stable launch of AM radio, effective operation and maintenance of broadcasting equipment, NHK is using all-solid-state transmitter instead of ordinary vacuum tube transmitter. This transmitter uses field-effect transistors (FETs) as power amplifiers. In order to meet the needs of high-power transmitters with output powers equal to or greater than 20 kW, NHK has jointly developed a THE-51 electrostatic induction transistor (SIT) for high-frequency high-power broadcasting with Tokin Corporation. NHK uses this SIT for the 20kW AM radio transmitter manufactured for the current fiscal year and will be used on a 100kW transmitter manufactured in 1989.