BUILD CARD · EASY

Morse Code LED

A safe LED variation of manual Project 103 for practicing short and long light pulses.

Time
15 min
Age
8+
Pieces
6
Board
10×7
Learning goals
  • Build and check a 10×7 snap-grid circuit from a visual diagram.
  • Short and long button presses encode information as visible dots and dashes.
FINAL CIRCUITBOARD 10×7
Morse Code LED final circuit diagram with labeled electronic components
Morse Code LED — final 10×7 snap-grid layout.

02 / PARTS CHECK

Parts list

  • 7-snap wireconnector
  • 3-snap wireconnector
  • White LEDsemiconductor
  • 100 Ω resistorresistor
  • Press switchswitch
  • 3V two-cell battery holderpower

03 / ASSEMBLY

How to build the circuit

  1. 1

    Disconnect the battery and clear the base grid before placing any part.

  2. 2

    Match the final diagram one grid position at a time, placing connecting wires and lower layers first.

  3. 3

    Check the direction of every LED, diode, transistor, battery, and other terminal-sensitive part.

  4. 4

    Press every shared snap firmly, check that no wire shorts the battery, then connect power last.

04 / FIELD NOTES

How it works

Short presses make dots and longer presses make dashes.

The resistor limits LED current during every pulse.

A planned pulse pattern can represent letters and numbers.

THE IDEAShort and long button presses encode information as visible dots and dashes.

05 / TEST

Test and expected result

What to do
Send three short, three long, and three short light pulses.
What to expect
The LED displays the SOS Morse-code pattern as dots and dashes.

06 / SAFETY

Build smart

  • Use only the 3V two-cell battery holder.
  • Never connect the battery terminals directly together.
  • Disconnect the battery before moving any component.

07 / TROUBLESHOOTING

If it does not work

  • Press every overlapping snap down firmly.
  • Check the battery direction and replace weak batteries.
  • Compare every component position with the final diagram.

08 / FREQUENTLY ASKED QUESTIONS

Questions about this circuit

What is the main idea behind this circuit?

Short and long button presses encode information as visible dots and dashes.

What should I check first if it does not work?

Press every overlapping snap down firmly.