| 摘要 |
<p>The antenna filter network protects against parasitically induced signals in networks associated with local high powered transmitters. The filter is a four terminal i.c. network (10) with a series i.c. circuit (12) to ground from the screens of the incoming (14) and outgoing (19) coaxial cables. It has low impedance within the passband and high impedance outside it. When used with an antenna fed either with twin wire feeders or coaxial cables, two such units are connected symmetrically in parallel. Input and output connections to the four terminal networks are via variable coupling transformers, the series, i.c. circuits are housed within separate screens inside the overall screen.</p> |
