I'll add a few comments based mostly on my Colorado days
when I had both a decent vertical and an inverted-V at 145'. I very
often saw post-sunrise conditions favor the inverted-V, even though
pre-sunrise almost always favored the vertical. Usually the vertical
was about 10 dB better before sunrise, then they would both be
equal at exact sunrise, then the inverted-V would be 10 dB better.
I did many, many tests with VK's and this was very consistent.
I believe the post-sunrise peak is high-angle for the following
reason. Beverages and verticals are both low-angle antennas and
are therefore very complementary. After sunrise, in addition to the
vertical being down on transmit, the Beverages would become poor
for DX stations (but still good for local USA which was probably
still low-angle). I remember when I first worked YB0ARA (when he was
near Jakarta before he moved to /9 in Irian Jaya ) well after sunrise. He
was perfectly readable on the inverted-V but was inaudible on any Beverage.
So yes, I believe there IS a post-sunrise peak, especially for high-
angles. Eventually I plan to put up an inverted-V here in NC but have not
done it yet.
73, Bill W4ZV