my r7 vertical resonates about 450khz too high on ALL bands. This antenna is 15 years old, all dimensions are correct, and it suddenly jumped in resonance after working perfectly for years...nothing has changed physically...just resonates way too high all of a sudden...cap problem in matching network?...something else in the black box?...any ideas?...contact direct at coyotevergreen at q dot com. Thanx. K0SDC