User manual

Metal Detector

Bend the strips outwards using a sharp edge. Cut two

slits into the bottom of the cup right and le to the center.

One of the slits shall be 38mm long, the other one 23mm.

The distance between the slits is approx. 5–8mm.

Push the piezo buzzer through the slits so that it is

held by the remaining strip between the slits. Make sure

to clamp the buzzer as tightly as possible. Now you mount

this self-assembled speaker above the sound holes in the

ﬂap lid. For this purpose, you attach the bent strips with ad-

hesive tape at a suitable location on the lid. If the diameter

of the cup is too large so that the speaker overlaps with the

circuit board, you can safely cut oﬀ a piece of the cup side.

Fig. 2.7:

Piezo speaker