I would check the coil in the hand piece. Either try a different base or
open by twisting. The hand piece coil is accessible. I fixed one that had
opened and needed resoldering.

"pedro" wrote in message
...
The Braun Triumph 3738 toothbrush and 3731 charger use an inductive
coupling arrangement to charge the toothbrush battery. Right now
SWMBO's unit isn't charging and I'm tasked with fixing it. Does
anyone know if this operates at line frequency or something higher?
(That will help sensing the field from the charging base to verify it
is operational before I disassemble the toothbrush itself.)