Instructions

41
Game and Knowledge in Electronics-Lab
Build your own doorbell! For the doorbell,
you will need the push-button and the
loudspeaker, which are connected to the
micro-controller as done previously. The
corresponding programme is selected with
40
Ding-dong doorbell
PROG
PB1 PB2
A
two wire connections A-C and D-E. Find a
suitable piece of string and make a loop at
the mounting plate. You can then hang the
bell on the door handle. Only people who
ring the bell may enter!