Remote Doorbell Warning Switch
Important Note:
This circuit should only be used with the solenoid type chime doorbells, the
electronic type that play tunes will not work here.
Notes:
The hardest part for this circuit was the title. It is quite easy to miss the
sound of a doorbell if you are watching TV , this circuit gets round the problem
by providing a visual indication, i.e. a lamp. As an alternative, a LED could
also be used. You could just parallel a lamp across the doorbell, but this would
mean extra drain from
the doorbell batteries or transformer. Using a series resistor R1 actually
reduces current flow , and if run from batteries, will give them a longer life.
The value of R1 is chosen so that about 0.6 to 0.7 volts is dropped across it,
and the doorbell should
still ring. I used a combination of a 22 ohm resistor in parallel with a 50 ohm.
The doorbell still rang and circuit operated correctly. I used to have an
electromechanical counter that registered each time when someone pressed the
switch....in fact, I remember a time when I had more "hits" at my doorbell then
at my web site=:)
Title: Remote Doorbell Warning Switch
electronic circuit
Source: www.electronics-lab.com
Published on: 2005-02-10
Reads: 1012
Print version:
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