The recent TechNet message on the effect of nickel on high frequency 
transmission lines was of interest and we are seeking information on the 
following:
     We have several fabricators suggesting we replace hot air leveling with 
and alternative such as electroless nickel-immersion gold, electroless 
palladium, or just leave the surface bare with an organic surface protector. 
 The boards are Teflon based and dielectric constant can be as high as 10.8. 
 Sounds like nickel is not such a great idea, does anybody have experience 
or data on palladium or just leaving the surface bare on microwave boards? 
 What is the effect of Palladium?  Does the naturally occurring copper oxide 
on the bare board affect performance?

Ted Edwards
602-436-3027
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