Understanding a simple electronic device

[morphex]

Hi.

I've studied a little about electrical and electronical devices, and this Christmas I bought a simple kids set to create an alarm from scratch.

I was wondering if you could help me understand how it works.

See attached photos on my Google Drive:

2 new items by Morten W. Petersen

photos.app.goo.gl

Points 15-16 are an alarm enable/disable switch, points 8 and 12 are for connecting to a simple on-off sensor.

-Morten

 

[danadak]

Basically "walk" the path, starting at + of battery (red lead) and see where it takes you.

If you come to a switch think bridge when its closed, no path if its open.

And see how you get all the way back to the - lead of the battery (black lead).

If you walk a path that goes thru switch, an R, an LED and get back to - lead of
battery then LED is lit when path is continuous, eg. switch is closed.....

Note LED is a diode, so it is polarity sensitive, one way no current will flow thru
it, polarity opposite configured it conducts and lights up.

Diode Basics for Beginners (Simple Guide, 2024)

In this post, I share everything I know about diode basics. I wanted someone to teach me these basics when I was learning about diodes myself.

www.yamanelectronics.com

Regards, Dana.

 

[camerart]

Hi M,
Note, that an LED must have a current limiting resistor in line with it to keep the current at the correct level, so don't connect a battery straight across the LED or it will glow too brightly for a very short time.
C.