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Showing posts with the label Lamp

Fog Lamp Sensor

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For several years now, a rear fog lamp has been mandatory for trailers and caravans in order to improve visibility under foggy conditions. When this fog lamp is switched on, the fog lamp of the pulling vehicle must be switched of to avoid irritating reflections. For this purpose, a mechanical switch is now built into the 13-way female connector in order to switch of the fog lamp of the pulling vehicle and switch on the fog lamp of the trailer or caravan. For anyone who uses a 7-way connector, this switching can also be implemented electronically with the aid of the circuit illustrated here. Fog Lamp Sensor Circuit Diagram:   Here a type P521 optocoupler detects whether the fog lamp of the caravan or trailer is connected. If the fog lamp is switched on in the car, a current flows through the caravan fog lamp via diodes D1 and D2. This causes the LED in the optocoupler to light up, with the result that the photo-transistor conducts and energies the relay via transistor T1. The relay ...

White LED Lamp

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Nowadays you can buy white LEDs, which emit quite a bit of light. They are so bright that you shouldn’t look directly at them. They are still expensive, but that is bound to change. You can make a very good solid-state pocket torch using a few of these white LEDs. The simplest approach is naturally to use a separate series resistor for each LED, which has an operating voltage of around 3.5 V at 20 mA. Depending on the value of the supply voltage, quite a bit of power will be lost in the resistors. The converter shown here generates a voltage that is high enough to allow ten LEDs to be connected in series. In addition, this converter supplies a constant current instead of a constant voltage. A resistor in series with the LEDs produces a voltage drop that depends on the current through the LEDs. This voltage is compared inside the IC to a 1.25-V reference value, and the current is held constant at 18.4 mA (1.25 V ÷ 68 Ω). The IC used here is one of a series of National Semiconductor ‘sim...

20W 40W Fluorescent Lamp Inverter Circuit Diagram

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This is certainly a low-cost 20W/40W fluorescent lamp inverter circuit project. Even so the maximum effective would be to make use of a 40 watt tube (or two 20 watt tubes in series). It is a circuit you may put collectively from junk box parts or assemble from a kit. It certainly is quite easy to construct and no need printed circuit board. The transformer is hand-wound on a ferrite rod (from an old transistor radio) and the winding wire could be salvaged from an old transformer. We’re intentionally maintaining bills down to confirm how cheaply it could be put together. 20W/40W Fluorescent Lamp Inverter Schematic Dependant upon your stock of components, the cost could vary from $3.00 to about $15.00 and in case the wires from the transformer are soldered to the ends of the tube(s), you are able to make a free-standing light that can be set-up in the garden to light up a dark place without having the worry of operating 240v wiring. The cost of powering the circuit is about 22 watts and ...