Mission 688
Signal Hill: Send a Secret Code Across the Sea
Badge: Code Breaker
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Build a radio tower with a note block code machine and send a secret.
1901. A faint click-click-click crosses the Atlantic. Build your own tower and send a code nobody can crack.
- New skill Wiring note blocks to buttons
- Level 7 · Time Travellers
- Difficulty Intermediate
- Mode Creative
- Time 40–50 min
- Ages 13+
What you’ll build
Build a tall radio tower on a hilltop with a radio room at its base. Wire two note blocks to buttons for a high dot and a low dash, tune them and test them with SOS, then send a secret word in Morse code and time your decoder.
Finish line: Your radio tower sends dots and dashes, SOS works and your decoder has cracked your secret word.
Bonus challenge: Add a redstone lamp at the top of the tower that flashes with every signal, so ships can read your message by light as well as sound.
You’ll need
- Iron bars
- A lightning rod
- Note blocks
- Buttons
- A Morse code chart
- A decoder
You choose
- My station's call sign
- Dot sound and dash sound
- My secret word (5 letters or fewer)
Stuck?
- Note block silent? It needs an empty space directly above it to play.
- Both sounds the same? Tap one to change its pitch, or put a different block under it.
- Decoder confused? Leave a short pause between letters and a longer one between words.
For grown-ups
Get this mission
This mission is in Mission Pack 68. Each printable has the full steps, a Plan & Log page and a parent page.
Print one mission at a time. You never need to print everything.
Played on Minecraft Bedrock on iPad. Buttons can differ on other devices and versions.