"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.)

It's an air-cored transformer in its simplest form, with absolutely no
"smarts" in the base unit - meaning you'll have 50Hz emanating from the
base.

Whereas with most battery-powered devices you expect the charge to gradually
diminish, with these units the base unit usually fails long before the
battery starts deteriorating. Almost invariably, the coil in the base goes
open-circuit.

Good luck in getting the base open (my one attempt revealed liberal use of
epoxy), and when (or rather, if) you do, good luck in re-winding the coil.
Given the time of year, you might just want to kill the proverbial pair of
birds by buying her a new one - it'll be far less hassle.

--
Bob Milutinovic
Cognicom