Bell rings when garden gate opens?
On Jun 17, 6:29*pm, Timothy Murphy wrote:
My small city garden has a standard Victorian railing
on the street, with the gate as part of the railing.
A few days ago someone came in the garden and stole
a (locked) bike.
This made me wonder if there is any simple way
to make a bell ring when the gate is opened?
Also, is there a standard spring which will
keep the gate closed?
If you can arrange a switch to close as the gate opens, connect it
from battery/wallwart to bell via a big capacitor (eg 4700uF) so the
bell only gets a pulse of power when the gate opens.
NT
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