I've been ignoring an input SWR problem on my Centaur for a while and decided to take a look at it today. 10 and 15 are higher than the others, (about 1.8 to 1) The others range from 1.1 to 1.3 to 1. Is that typical? If not, the 81763 10/15 meter optional filter board seems to be a likely culprit, but there's not much circuitry on it. Thanks, Joe, K8MP