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一、概述全固态电视发射机以其高效率、低运行成本、性能稳定、停播率低、模块寿命长、维护量少等优点,再加上技术日趋成熟,得到了广泛的推广与使用。我台于2000 年购进一台北广产 VHF 固态发射机,该机由厂方来人进行了组装与调试后投入使用。在使用近两年的时间内,末级功放单元发生了多次损坏功放管的故障。该机末级功放模块采用菲利浦公司的 BLF278金属膜绝缘场效应管(MOSFET),属半永久性器件,正常状态下工作寿命很长,而损坏的 BLF278中工作时间最长的才达
First, an overview All-solid-state television transmitters with its high efficiency, low operating costs, stable performance, low stop-broadcast rate, long module life, less maintenance and other advantages, coupled with increasingly sophisticated technology, has been widely promoted and used. I Taiwan in 2000 to buy a North Canton VHF solid-state transmitters, the aircraft came from the factory after the assembly and commissioning put into use. In the past two years, the power amplifier unit failed several times to damage the power amplifier tube. The final power amplifier module uses Philips BLF278 metal film insulation FET (MOSFET), is a semi-permanent device, the working life is very long under normal conditions, and the damaged BLF278 in the longest working hours of the talent