Dave Plowman (News) wrote:
In article ,
ian field wrote:
A good clue as to whether its a piezo sounder is that some other
component would provide a DC path for the collector of the driver
transistor - maybe an inductor or just a resistor if its a real
cheapie.

Isn't it easier just to look at it? A piezo sounder looks nothing like a
moving coil speaker.

The manual is available here,
http://www.pestingers.net/Heathkit_m...sequential.htm

I assume the OP has it but for others trying to help in the manual the
speaker looks like a normal moving coil speaker