Thanks for the info... I'm should have added that the one I was
working with was contained in RF transparent plastic tube. So that's
how I can mount the whole thing right next to the mast. Maybe if you
were using a traditional copper model, it might be different. But with
the one I have, there was no difference with the mast next to the stub
section. Though I have noticed similar commercial models do seem to
leave an air gap between the mount area and the element.