Filter for coaxial cable coupling - uses coaxial ceramics resonator for providing frequency selective filter

摘要

The filter uses an interchangeable coaxial ceramic resonator (24) which is electrically coupled to the outer conductor (10) of the coaxial cable. The ceramic resonator acts as a frequency selective filter, with a variable bandwidth. Pref. the ceramic resonator (24) is screwed to the inner conductor (30) via a hollow screw (20) extending radially. The hollow screw also houses spring discs (26) with sealing rings (27, 28) for providing a water-tight seal. The ceramic resonator (24) is pref. made of a material with a high dielectric constant for reducing the overall size when handling frequencies in the lower MHz range. ADVANTAGE - Narrow bandwidth and improved noise isolation.