For the past couple of months, my clock/radio light, on occasion, will
go dim and then brighten back up, dim and brighten back up.  This will
happen for a few minutes and then stop.  No problems for days/weeks
even.  Then, it will start again.  About a month ago I started my car
and had no light on the radio at all.  After driving for a couple of
minutes it came on.  All other interior lights were working.  I also
notice sometimes when I am parking that my headlights will dim and
then come back full strength.  Like when I'm breaking, shifting from
drive to reverse or vise versa is when I notice it.  I had my
alternator replaced about 4 months ago.  Thinking that maybe I got a
bad one, I took it to my mechanic who hooked my battery? up to a
voltage reader (sorry, I don't know the correct name) and the reading
was a steady 14.  Any ideas?