This is an outdoor aerial system designed for interference suppression. It consists of a length of multi-stranded copper wire, two aerial insulators, an aerial balun transformer and a receiver balun transformer.

The principle behind it is that it allowed aerials to be erected far away from power lines and other forms of interference without introducing signal losses because two core balanced screened cable is used to connect the balun transformers together (the screened cable had to be bought separately). The large screw on top of the aerial balun connects straight onto one end of the long-wire aerial and the base of the balun can be removed to attach the screened coax. The receiver balun would be situated indoors and the other end of the screened cable would connect to the terminal block in the receiver balun base. The red wire from the receiver balun goes to the receiver aerial socket and the black wire goes to the receiver earth socket.

 

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