The daytime sensors present in Minecraft are used to detect the time of day since they are able to measure the intensity of sunlight and to emit a current signal of equivalent intensity that can be conveyed in a circuit created with the Pietrarossa powder. When paired with special Redstone blocks, they can be used as a twilight switch to detect nightfall. These capabilities make them perfect for crafting various objects, such as an alarm clock, time bomb, twilight switch, and many more.
Steps
Method 1 of 4: Basic Alarm Clock
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Step 1. Place a day sensor where you want it
You can also cover it with a block of clear material.
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Step 2. Create a redstone dust circuit that connects the sensor to a machine that can be activated by the current produced by the circuit
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Step 3. When sunlight hits the sensor, the connected machine will be activated automatically
Method 2 of 4: Time Bomb
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Step 1. Place a TNT block wherever you want
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Step 2. Hide it well so it won't get noticed
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Step 3. Place a daytime sensor on top of the TNT block
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Step 4. When sunlight hits the sensor, the TNT block will explode
Method 3 of 4: Inverted Daytime Sensor
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Step 1. Place a day sensor where you want it
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Step 2. Place your character next to the day sensor, then press the "Use" button
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Step 3. The day sensor will turn blue
In this way it will work exactly like a real twilight switch and will only activate when the night arrives.
Method 4 of 4: Auto Turn On Lights
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Step 1. Place a daytime sensor on the roof of your home
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Step 2. Use the "Use" command to turn it into an inverted day sensor
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Step 3. Create a redstone dust circuit that reaches where you want to place the redstone lamps
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