I seeking any information on the effects that changing from
difunctional epoxy FR-4 to tetrafunctional epoxy
(UV-blocking) FR-4 on high frequency circuits in the 200MHz
to 600MHz range.  The industry is forcing this change and
we have many customers that will require requalification of
products to them if component changes are necessary.  We
are presently designing experiments for testing various
parameters based on a typical high frequency pattern.  Any
information and suggestions are appreciated.