jason's psyche kindly pointed out to me that my Google ads were coming up as errors on the Blogclicker frame.
If you visit her excellent blog, there is an article in the June archives that tells you how to fix this problem. As you don't see your own blog while surfing, it is unlikely that you will notice anything amiss until it is pointed out.
Again, many thanks to jason's psyche for the kind help.
Mike Hitchen