摘要 |
<p>A method and apparatus for locating the source of noise ingress into a CATV system return path (16) by coupling a filter (18, 18') having a passband in the noise frequency bandwidth to the nodes between adjacent return path amplifiers (22l, 22m, 22n). The filter (18, 18') is sequentially coupled to the nodes, working away from the CATV system headend (30). A signal level meter (50) or the like monitors the effect on the noise of coupling the filter (18, 18') to the nodes. When a node is reached at which coupling of the filter (18, 18') to the node no longer has any effect on the signal level in the node, the source of the noise is isolated in the node immediately preceding the node under test.</p> |