Lighting Circuits
- Page 2-
This circuit changes the average value of the dc supply voltage because of the high switching frequency. The tungsten lamp will have an almost continuous adjustable light output between 0 and 100%.. -
The 5AH will trigger when the voltage across the two 0 juF capacitors reaches the breakdown voltage of the lamp. Control can be obtained full off to 95% of the half wave RMS output voltage.. -
This simple circuit providers battery operated emergency lighting instantaneously upon failure of the regular ac service. When line power is restored, the emergency light turns off and the battery recharges automatically. The circuit is ideal for use in.... -
An input signal of less than 1 mA and 1V is required to switch on CS1. As long as this input -signal is maintained, CS1 will conduct during each positive half cycle of anode voltage, thereby energizing load LI with half-wave rectified dc. L2 remains.... -
The shift pulse amplitude is less than 15 volts. If a stage is off, the shift pulse will not be coupled to the next stage. If it is on, the diode will conduct and trigger the next stage. Just prior to the shift pulse the anode supply is interrupted to tum.... -
This circuit uses a low-input-bias op amp to give a steady dc indication of light level. To reduce circuit sensitivity to light, Rl can be reduced, but should not be less than 100 K.. -
The meter reading is directlyjproportiona! to the logarithm of the input light power. The logarithmic circuit behavior arises from the nonlineardiode pnjunction current/voltage relationship.. -
This counter uses a four-digit display, but with a flip of the range switch, it can display frequencies from 1 to 40 MHz, with a resolution of 100Hz. The MM74C926 CMOS IC contains a four-digit decimal counter that can latch a given count and then use this.... -
The circuit consists of ICM7208 seven-decade counter U1, ICM7207A oscillator controller U2, and CA3130 biFET op amp U3. IC U1 counts input signals, decodes them to 7-segment format, and outputs signals that are used to drive a 7-digit display. IC U2.... -
This CMOS circuit can be used as a 1-shot time delay switch and general-purpose timer. The circuit consists of a gated oscillator and a latch made from one CD4001 quad 2-input NOR gate as shown and a CD4020 14-stage counter. TON is a function of the.... -
This circuit can be used to measure frequencies up to 40 MHz. To obtain the correct measured value, it is necessary to divide the oscillator frequency and the input frequency by four. .. -
By using the preamplifier with a short length of shielded cable and clip leads, signals that generally could not generate a readout, generate precise and stable readouts on the counter. The DPDT switch is used to bypass the circuit when amplification is.... -
The output of the CA3179 is fed through the Dl!Q1 circuit. Those components serve to boost the 1-V output of the CA3179 to a standard TTL level. Then, depending on the position of range switch S2b, the signal is passed directly to the 7216, or through the.... -
Opening SA, changes the indicator lamp from flashing to steady-lit condition. The 6-V incandescent lamp on the collector of Q2 requires about 0.3 A. A 1-KO load resistor limits Ql"s collector current to about 6 mA. .. -
The circuit is built around two power FETs, which are configured as a simple astable multivibrator to alternately switch the two lamps on and off. The rc values given sets the flash rate to about 1/3 Hz. By varying either the resistor or capacitor.... -
This circuit is suitable for fitting into slide projectors without a dimmer facility as witb 24-Vac fed halogen lamps. With a few small alterations, it can also be used for dimming 12-V halogen lamps, but not those in a car, because these are fed from a de.... -
This pseudorandom sequencer drives a solid-state relay. If you power a low-wattage lamp from the relay, the lamp will appear to flicker like a candle"s flame in the wind; using higher-wattage lamps allows you to simulate the blaze of a fireplace or.... -
The lights seem to dance in time with the music. Line-voltage lamps of about 40 to 100 W do nicely. The current for the lamp is from an SCR. When low-level audio is present across Tl, SCR1 is not triggered into conduction. A louder signal, however,.... -
Lamp life can be extended by improving the conditions under which its filament is operated. This includes eliminating the inrush overcurrent surge and reduclog the mechanical stress (vibration) on the filament caused by an ac source. The circuit shown.... -
This circuit uses a PUT for phases control of an SCR. The relaxation oscillator formed by Q2 provides conduction control of Ql from 1 to 7.8 ms or 21.6° to 168.5°. This constitutes control of over 97% of the power available to the load. .. -
The dimming action is controlled by varying the amount of current passed through triac Q4 and, thus, the lamp plugged into ac receptacle SOL Unijunction transistor Q3 operates as a relaxation oscillator whose output pulse frequency depends on how fast.... -
At half brightness, the lamp current is pulsed on and off (Fig. 50-12b) by the voltage developed across the resistor and capacitor at the current-sense output. Lamp current is sensed by the current-sense output. A simple pulse-width modulation.... -
A 1-V amplitude pulse triggers SCSl, but has insufficient amplitude to trigger SCS2. A 3-V input pulse is delayed in reaching SCSl by the 10-KO and .001-!"F integrating network. Instead, it triggers SCS2, then raises the common emitter voltage to prevent.... -
Assume first that SCR1 is on and SCR2 is off so that CI is fully charged, with its LMP2 end positive. The.. -
A three-way switch to control a lamp (off-dim-bright, etc.) uses an NE555 timer to generate a one-second pulse, trigge.. -
This unit uses a Nicad battery to provide power to an emergency lighting setup. When power fails, T1 beco.. -
This hookup is useful in some house wiring situations, where only two wires are available between switches, rather than.. -
The circuit presented here guarantees that if bulb Lai "gives up the ghost," bulb La2 will take over its tas.. -
After the SCR turns on, CI charges up to almost the full supply voltage via R3 and the anode of the SCR. Whe.. -
The ac line power is brought back into the circuit through Fl, a protective 5-A fuse. One side of the ac line is connected to one side of each ac outlet. The other side of the ac line is connected to each SGR or silicon-controlled rectifier. Each SCR is, in.... -
The automatic porch-light control circuit holds a triac on until a 4020 divider counts a number of 60-Hz powerlinc pulses. The circuit turns off a light after a predetermined time by using pins other than pin 3 of III. Various times can be set... -
You can turn any ordinary household bulb into one that shimmers or blinks. This circuit works on any incandescent light up to 200 W, arid runs on standard 120 Vac. The circuit uses an SCR to cause an ordinary lamp to sliimmer. Note that one side of the lamp....
New Circuits
-
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of.... -
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is.... -
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to.... -
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This.... -
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the.... -
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,.... -
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the.... -
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power.... -
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
Popular Circuits
The design objective was to produce an hFE tester with switched collector currents for the DUT...
The pitch of the tone is dependent upon the resistance under test. The tester will respond to...
For a dark photocell, high resistance, the vohage across the diac rises rapidly with the line...
This circuit is useful if you need a low-energy flashing alarm. The 200 to 400-dc supply should...
Circuit diagram is very simple and works as follows: N1 Schmitt trigger works as an oscillator...
Use this in your garden and listen for any unusual sounds, or maybe just wildlife noises. If you...
A module of modules: 3 dome filters, 4 ring modulators and some summing/differencing amps...
A touch switch for a USB powered desk lamp, and the touch switch isn`t working. The circuit...
This circuit shows how to use an ordinary LED as a light sensor. It makes use of the photovoltaic...
When no light, photocell PC1, PC2 was high resistance, Q1, Q2 is turned off the relay contacts...
If the CMOS circuit load (actuator) is a relay device, the circuit must have a large load...
TDA1308 is class AB headphone driver IC Philips recently launched its biggest feature is the...
AMP - 04 is a single-supply, single resistor gain adjustment, the input voltage drift of less...
Circuit shown in Figure 3-115. It uses contactors and double buttons, so when converting speed...