DiscoverCircuits.com -- Hobby Corner
Last Updated on:
Tuesday, June 01, 2021 03:06 PM
Hobby Circuits List
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LINK to Dave's circuit, but DO NOT COPY any files to your WEB
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More
Lamp Controls
Switches |
12v Light/Dark Switch |
Often, for certain low voltage lighting systems; you would like to turn off the
lights during the bright light of the day. Most commercial day/night switches
are designed
for AC lighting. This hobby circuit below was designed
for a 12v
DC system. But, it could be modified for other voltage as well. It uses
an inexpensive phototransistor as the light detector. An n-channel FET is used
to switch power to the lights. A transistor circuit is included to provide
some hysteresis. This keeps the circuit from fluttering the light during the
transition from day to night and night to day. It is recommended that a
plastic tube be placed over the transistor to prevent it from being illuminated by
the lights it is controlling. By selecting the appropriate power FET, the
circuit could control over 100 watts worth of 12v lighting. (July 22,
2008) |
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Click on Circuit Below to view PDF of Schematic |
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