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: 1057
        Print version: ![]()
Other electronic circuits and schematics from Security and other sensors and detectors
-  
Police Siren
 -  
Factory Siren
 -  
Sound Operated Switch
 -  
Mains Remote-Alert
 -  
Field-strength meter
 -  
Infrared Alarm
 -  
Metal Detector
 -  
IR transceiver 1.0
 -  
UltraSonic Radar
 -  
Big Ben Sound
 
