Tutorials/Day and night detector

Day and night detectors are mechanisms in which allows for the player to detect what time of day it is.

Making the circuit

 * Place the detector in an appropriate place, near a house.
 * Place lamps in an outer wall. Note that they must be visible from inside.
 * Connect the detector to a NOT gate, for best effect have a distance of 5-6 blocks.
 * Connect the NOT gate to the lamps.

Thanks to the Java Edition 1.8 update, there is an easier way to do this:
 * Place the detector in an appropriate place, e.g. near or on top of the home.
 * Place the lamps in an outer wall. Again, they must be visible from the inside.
 * Connect the detector to the lamps.
 * the detector

Uses
This circuit can be used for many things, including
 * Turn on lights inside or outside
 * Turn on in-ground "street lights" to prevent mobs from spawning in a certain area
 * Use lights to prevent spawning, and combine with other defenses to keep mobs out of the house (For example, the player could make a drawbridge that retracts at night, or something to automatically kill mobs outside the door in the morning, hooked up to the same circuit that will reduce mob spawning in the first place).
 * Use an AND gate to create a circuit that will only work at day, or one that will only work at night

BUD Method
This method of time of day detecting uses a block update detector.

Video
Детектор дня и ночи