I've got a Kundo clock which doesn't work. A clock shop near me advises that it looks complete from the photographs but it might be the coil which has failed. Any ideas where I can get one please and is it easy to fit?
There were two types of transistor clocks. The newer ones
used an external circuit board and the coil assembly was only a coil.
This type used a single coil winding and two transistors plus some
components mounted on the external board in the base.
The older type has the transistor and resistor inside the coil assembly.
These used the two coil windings as shown in the pictures, if you follow
the pointers in the treads.
The coils are wound with #42 magnet wire ( smaller than a hair ).
The original coils have a clear potting material holding them to the bobbin
and can not be unwound easily without breaking the wires.
The common failure is not the transistor ( although I worry some about your
battery holder. they are designed to run on 1.5V ) but the coil going
open. This is caused by the insulation decomposing and creating a corrosive
material. The wire I'm talking about is the fabric wire covered wire producing the
corrosive material not from the magnet wire. The magnet wire is what fails.
These coil assemblies are not available any more and haven't been manufactured
They can be rebuilt. see :