View Single Post
  #7   Report Post  
Old January 10th 05, 06:25 AM
Brian Reay
 
Posts: n/a
Default


"Alun" wrote in message
...

Plus, of course, the issue isn't so much the power as the current when
thinking of high resistance connections. The cranking current drawn via
a car battery terminal is around 100A. If the grease ingress caused a
high resistance connection, the car wouldn't start. In practice,
ungreased connections tend to 'go high' due to corrosion.


It's not normally grease, it's vaseline, which is conductive. I don't know
how vaseline behaves at RF, though. Maybe not too well?


If it isn't in the the current path (ie between the mating surfaces) and
also not acting as an unwanted path (eg between the earth clap and the
antenna), does it matter? OK, you may get some local absortion of RF energy,
but how much grease are you going to use? Not enough to absorb much RF and
the mass of grease (or vaseline) will be far less than other unquantified RF
conductors and absorbers in the vicinity.

You need to look at things like this in the context of the problem.

--
Brian Reay
www.g8osn.org.uk
www.amateurradiotraining.org.uk
FP#898