A method for jam and monitoring of a large have in common shaft - an antenna system

摘要

The aerial has pilot frequency controlled hf amplifiers. A testing lf signal, different for each amplifier is modulated in the head station onto a pilot frequency near to the transmitted useful frequency band (HF), which serves for level control of the amplifier. The modulated pilot frequency is separated at the output of each amplifier to be tested and rectified. The low frequency (NF), obtained by rectification, which is selected and passes only the low frequency associated with the respective amplifier. - The lf signals, passed by the different filter networks are fed back via the hf cable network to the head station, where they are separately evaluated. Pref. the most distant path amplifier in the hf cable network is continuously checked and monitored. Its associated lf is evaluated in the head station by an audio or video alarm signal and possibly sent further.