Gadget: Door Bell That Does Not Need Battery

Date:  Feb 6, 2014

Problem

What is a function of a door bell?

When your guest press the door bell, you should be able to hear that and open the door.

But sometimes, if you are inside your room, and you can’t hear the door bell, then, how?

I am sure that the door bell has been installed when you renovate the house, and it is actually “hard wired” and concealed under the wall.  So, you can’t actually move the door bell (the ringer).

Solution 

Introducing the door bell that does not need battery.

But it needs “electricity”.  Wahahaha.  

OK.  You don’t need to put battery on any of these devices.  Basically, you press the door bell on the left, and the ringer on the right will DING DONG.

Door bell ringer.

You need to plug this in any of the power socket.  It does not need battery, but it needs electricity.

So, what exactly he meant by "no need battery"?

The door bell (the one that you press) no need battery to operate.  Apparently, the body temptation is enough to trigger some mechanism within the door bell and generate a faint WIFI signal to signal the ringer to DING DONG.  And it does it without any battery or electricity to transmit that faint WIFI signal.

It has to be within 200 meter.

I tis quite cool.  Let’s see how it works.

Here are some of the manual pages in Chinese.

Oh, it actually convert the mechanical and generate electricity.

oh.. it’s low frequency.  I like.

OK.  Now seriously, how do I use this?

If you think that for the next few days, you going to lock your door and work alcoholically in your room, better move the ringer closer to you and place it in your room.  So that if there is any one come to visit you. you still can know about it and open the door.

So, you can move around your door bell ringer and place it some where you can hear the ringing.  

 

Bought it from Taobao.  For RMB138 per set.