Showing posts with label light. Show all posts
Showing posts with label light. Show all posts
Saturday, September 28, 2013
Courtesy Light Extender
In essence, this circuit is a 15 to 20-second courtesy light extender for cars. It is activated in the usual way by opening a door but it also samples the negative lock/unlock signals from a car alarm or central locking and does two more things. First, when an unlock signal is received, it turns on the courtesy light for 15-20 seconds before you open the door. Second, when a lock signal is received, it turns off the courtesy light immediately, with no fade-out. This is done to eliminate false triggering of the burglar alarm through current drain sensing. When a car door is open or the unlock relay is activated, the 33µF capacitor discharges through diode D1 and this keeps transistor Q1 turned off.
This allows Q2 and Q3 to turn on and the courtesy lamp is activated. When the door is closed, the courtesy lamps stay illuminated and the 33µF electrolytic capacitor starts charging through the associated 1MO resistor. As the voltages rises, Q1 turns on slowly, turning off Q2 and Q3 which gradually fades out the courtesy lamp. If a lock signal from the central locking system is received, relay 1 closes and charges the capacitor instantly, so the lamp turns off immediately. Relays were used to interface to the central locking/alarm system as a safety feature, to provide isolation in case something goes wrong.
Read the rest entry[...]
This allows Q2 and Q3 to turn on and the courtesy lamp is activated. When the door is closed, the courtesy lamps stay illuminated and the 33µF electrolytic capacitor starts charging through the associated 1MO resistor. As the voltages rises, Q1 turns on slowly, turning off Q2 and Q3 which gradually fades out the courtesy lamp. If a lock signal from the central locking system is received, relay 1 closes and charges the capacitor instantly, so the lamp turns off immediately. Relays were used to interface to the central locking/alarm system as a safety feature, to provide isolation in case something goes wrong.
Sunday, May 12, 2013
Nokia C7 Camera Flash Light IC Problem Solutions
Nokia C7 Camera Flash Light IC Problem Solutions
Nokia C7 Camera Flash Light IC Problem Solutions
Saturday, April 13, 2013
Installtrailer Light Taillight Converter Towing
Looking To The Rear For The Trailer Plug The Pins Are Reversed And.
Trailer Wiring Diagram Light Plug Brakes Hitch 4 Pin Way Wire Brake.
Trailer Light Wiring Typical Trailer Light Wiring Diagram.
Trailer Parts Depot Trailer Wiring Kits Trailer Parts.
How To Install A Trailer Light Taillight Converter In Your Towing.
Wiring For 13 Pin Euro Plugs Sockets For Trailers Caravans Uk.
Trailer Wiring Diagram.
Wiring Color For 7 Pin Trailer Plug Jpg.
Trailer Wiring Diagrams Johnson Trailer Sales Colfax Wisconsin.
12s Wiring Diagram.
Wednesday, April 3, 2013
Simple Automatic Street Light System
The left hand side transistor T1 is rigged as a voltage comparator using a resistive network. The resistor at the upper arm is the LDR and the lower arm resistor is the preset which is used to set the threshold values or levels. T2 is arranged as an inverter, and inverts the response received from T1.
Initially, assuming the light level is less, the LDR sustains a high resistance level across it, which does not allow enough current to reach the base of the transistor T1. This allows the potential level at the collector to saturate T2 and consequently the relay remains activated in this condition.
When the light level increases and becomes sufficiently large on the LDR, its resistance level falls, this allows more current to pass through it which eventually reaches the base of T1.
The transistor T1 conducts, pulling its collector potential to ground. This inhibits the conduction of the transistor T2, switching OFF its collector load relay and the connected lamp.
The power supply is a standard transformer, bridge, capacitor network, which supplies a clean DC to the circuit for executing the proposed actions.
The whole circuit can be built over a small piece of vero board and the entire assembly along with the power supply may be housed inside a sturdy little plastic box.
The LDR must be placed outside the box, meaning its sensing surface should be exposed toward the ambient area from where the light level is required to be sensed.
Care should be taken that the light from the lamps does not in any way reach the LDR, which may result in false switching and oscillations.
Parts List
R1, R2, R3 = 2K2,
VR1 = 10K preset,
C1 = 100uF/25V,
C2 = 10uF/25V,
D1 ---- D6 = 1N4007
T1, T2 = BC547,
Relay = 12 volt, 400 Ohm, SPDT,
LDR = any type with 10K to 47K resistance at ambient light.
Transformer = 0-12V, 200m
Monday, April 1, 2013
Trailer Light Connectorwire Extension Cord
Trailer Tail Lights Running Lights Fog Light This Goes Converter.
Diagram 2004 Silverado Wiring Diagram Light Switch Wiring Diagram.
World S Best Resource For Restoring Upgrading 1967 2012 Camaros.
Wire Testers And Turn Park Lights On And Find That Wire Then 4 Ways.
Trailer Light Connector 4 Wire Extension Cord 12.
Tail Light Problem Trailer Wire Jpg.
2003 03 Grand Cherokee Trailer Light Wiring 118369.
Hooking Up Trailer Brake Lights Requires A Few Important.
Tm Tail Marker Tail Light Brown.
Trailer Wiring Diagram Light Plug Brakes Hitch 7 Pin Way Wire Brake.
Subscribe to:
Posts (Atom)