[LectronFanModerator]

Hi all,

This circuit is a 3 bit counter which can display the decimal numbers 0-7 in BCD code.

With the Schmitt trigger as clock generator, the counting goes automatically !
Very cool to see how the light bulbs switch on and off accordingly !

BCD stands for Binary Coded Decimal, this means that any decimal number can be expressed as a binary number.

I’ve included a small table in the circuit setup which expresses the decimal numbers 0-7 into binary.

A BIT is the shortest binary state and can be either 0 or 1
So, a 3 bit counter is a circuit that can count from 0 (in decimal, 000 in binary) up to 7 (in decimal, 111 in binary).

Some questions :

• Why do we use C1 and C2 in series ?
• What’s the equivalent capacitor value then ?
• Do you think we can make a circuit that counts back from 7 to 0 (decimal), or 111 to 000 (binary) ?
• Be sure to write your answers in the comments !

Here’s a setup and some pictures.

Greetings

 

[MichaelKeymaster]

Hi Frank,

Great introduction to the digital circuit design!  You’ve even included a little tutorial on the binary number system.  Awesome and so helpful, particularly to those just starting their journey into electronics.

How great that the Ausbausystem 3 (System 300) is still proving its worth all these years later.  Wonderful!

I wish that our recently deceased colleague Günther Stabe could enjoy all the great tutorials that you are coming up with!

Thank you so much!

• This reply was modified 3 years, 8 months ago by Michael.
• This reply was modified 3 years, 8 months ago by Michael.
• This reply was modified 3 years, 8 months ago by Michael.

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