7400 competition entry: Beeping down counter

Chris decided to enter another project into the Open 7400 Logic Competition. The beeping down counter, as it’s name suggests, is a pre-settable timer which beeps and uses a display to show the seconds left on the timer.

The goal of this project is to duplicate the down counting circuit used by the character Ivan Vanko in Iron Man 2 to aid his escape from prison in Manaco. There are three key components that go into this design:


  • A Down Counter With Dual 7 Segment LEDs
  • A Push Button To Initiate The Down Counting
  • A Quick ‘Beep’ Sound With Each Down Count

Via the contact form.

He also filmed a video of his project which is shown below.

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1 Comment

  1. its not working in my app. in livewire and multisim so i cannot convert it into the pcv..i thought it will work so i buy the components but when i try to simulate it does not working…i tried it many times but still it does not working…can you send me a better schematic diagram so i can convert it to a pcv layout and i can use it in my project?..ty..

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