Coverage map and push pin location don't agree?
 

I noticed that many times the coverage map page where it shows you colours of a station's strength (CALL SIGN LOCATOR feature) dont agree with the map where you can push pin your exact location.

For exampe, for call sign, I can put in CKVU or CHAN and I see a weak (purple?) colour in Magnolia area of Seattle. Yet when I go the the "pin point location" map, where I can put the push pin in that particular area, it doesnt show any signal at all for those stations... I would expect it to show the call signa station with a weak signal, maybe -5 or -10 NM, etc...

Basically, I want to use the features on this site to determine where my channels have some signal in a general neighbourhood, then use the pushpin to pick out a particular spot in the neighbourhood with the strongest signal there for my "next" nove. (heh).