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我台有四部中波发射机,两套广播节目,一套为转播河北省台节目,频率为1278kHz.另一套为本台自办节目,频率为954kHz.由于地势所限,只有1付铁塔作为发射天线,去年实现了双频共塔的工作.954kHz主机为1kW屏调机,备机为1kW脉宽调制机,馈线为75Ω电缆.1278kHz主机为10kW屏调机,备机是1kW脉宽机,馈线为六线式鼠笼式天线.我台经过反复研究实现了两机自动上天线的工作.转播台1278kHz两回两台发射机主机为甲机、备机为乙机,原理如图1.
There are four medium-wave transmitters in Taiwan, two sets of radio programs, one is a program broadcast on Hebei Province, with a frequency of 1278 kHz, and the other is a program run by this station at a frequency of 954 kHz. Due to the limited terrain, only one tower As a transmitting antenna, last year achieved a dual-band co-tower work. 954kHz host 1kW screen machine, preparation machine 1kW pulse width modulation machine, feeder 75Ω cable .1278kHz host 10kW screen machine, preparation machine is 1kW pulse width Machine, feeder for the six-wire squirrel-cage antenna.Our station after repeated research to achieve the work of the two antennas automatically on the antenna.Transmission station 1278kHz two back two transmitter host A machine, preparation machine B, the principle shown in Figure 1.