reduce volume of quartz wristwatch beep

[rastapapa]

Hello,
My mother bought my kids digital wristwatches. Theyre great, but their beep is so loud. I remember someone telling me as a child that one could chip away the piezo crystal on the back plate of the watch to decrease the volume and the concept has always stuck with me. However, I havent seen any discussion of this online. Volume control is typically suggested by adding resistance, which may be challenging to do in a chinese wristwatch. using a small pliers or screwdriver to break away edge pieces of the crystal I presume should change (increase) the frequency, and perhaps drive it to the inaudible range. Is this feasible? Before I test it on my sons watch and risk killing the alarm completely I was hoping to get some others' opinions.

 

[73's de Edd]

Sir rastapapa . . . . .
I would go for mechanically damping the transducer element to the required degree with a small cotton / polyester ball / pad placed at its mechanical center.
Experiment with area and density of coverage, until deadening to that desired acoustical level.
Poly is preferred . . . . . quilt and pillow batting . . . . .due to its waterproof repression..
If like most units I have seen, the complete back case / disc with its transducer epoxy mounted to it is held on by 4 small SS jewelers screws.
NO do chippee-chippee to transducer disc ! . . . . . . . .¿ ¿ ¿ WHASSAMATTAHYOU ? ? ?

73's de Edd . . . . .

 

[kellys_eye]

Bluetack - that sticky stuff used to fit poster to your bedroom wall....... tiny ball squished onto the rear of the transducer will 'kill' the volume instantly.