Optical Sensing Circuits
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DC power supply can also be controlled via an optical fiber. The circuit is a small DC motor ( 1/12hp) providing an insulating speed control channel. The control logic is an in.. -
Fans (Ceiling) Fifth gear speed control circuit shown in Figure 3-6. It uses capacitor step-down, three-terminal fixed 7806 integrated steady voltage regulator Ai regulator to .. -
FIG sensitive ((InW) .OPA111 optical receiver amplifier feedback resistor of FIG 200Mn, because the gain of the amplifier is high .OPAI11 receiving signals transmitted over an .. -
Ethernet is the most widely used networking technology with high reliability, media informative, easy to expand and update, etc., in businesses, schools and other fields are wi.. -
Dimming control circuit as shown in FIG. Single-chip I/O port sinking method to achieve control thyristor switch and dimming control. MOC3041 optocoupler with internal zero-cro.. -
With the coupler biased in the linear region by the 10 mA dc bias on the IRED and the voltage divider on the phototransistor base, photodiode current flows out of the base into the voltage divider, producing an ac voltage proportional to the ac current in.... -
A circuit stabilizes the current-transfer ratio (CTR) of an optically coupled isolator used as a linear transducer. The optocoupler produces a voltage output that is proportional to—but electrically isolated from—the voltage input. However, the output.... -
The application involves observing the light pulse emerging from a thick specimen after transillumination by a laser pulse. Pulses derived from the laser source are amplified using a Video Amplifier LM733. The reference level is set to 1 V in the comparator.... -
Fiber Optic applications require analog drivers and receivers operating in the megahertz region. This complete analog transmission system is suitable for optical communication applications up to 3 MHz. The transmitter LED is normally biased at 50 mA.... -
To simplify the following schematics and facilitate easy understanding of the principles involved, the following schematic substitution is used (Note the triac driver is of limited use at 3 f voltage levels). .. -
The accuracy of direct linear coupling of analog current signals via an optocoupler is determined by the coupler linearity and its temperature coefficient. Use of an additional coupler for feedback can provide linearity only if the two couplers are perfectly.... -
Semiconductor color sensor having an identification of the object color capacity by three photodiodes PD1, PD2, PD3 and three color filters X-PHOTO, Y-PHOTO and Z-PHOTO constitution. Respectively mounted on each of the photo diode red (R), green (G), blue .. -
A reflex isolators (A) the light reflected by an object detecting its presence. When an object is very close to the sensor (B), this technique can be used to detect circuit. .. -
A, RS485 bus Introduction RS485 bus is a common serial bus standard, using balanced differential transmit and receive mode, and therefore has the ability to suppress common mod.. -
As shown by the bistable circuit and optocoupler transistor of FIG. In the initial state the moment the supply voltage is turned on, the transistor VT off, the circuit outputs .. -
As shown is a very attractive Christmas lights circuit. When the power is turned on, lights HL will gradually become brighter; when it reaches the brightest, it will automatica.. -
By the photocell photoelectric tracking circuit configuration, with two similar performance as a photoelectric cell the same light receiving device. When the incident light flu.. -
Circuit is shown. Group 4 analog electronic circuit switch (S1 ~ S4): S1, S2, S3 for parallel delay circuit, when the power is turned on by their R4, VB6 drive Triac VT, VT dir.. -
This document presents technical details, hardware and software of a complete imaging system which uses a fast CCD sensor and a 41 Msample/s A/D converter to acquire full-frame 12 bit/pixel digitised images with a time resolution of 1.25 ms/image. The noise.... -
The circuit in Figure 1 eliminates the need for adjustments. The circuit uses dc-coupled feedback to control the current in the output resistor. Hence, the output voltage is predictable and constant... -
This circuit will activate a relay when light falls to a preset level. Light level can be adjusted with VR1 and the relay contacts may be used to operate an external light or buzzer... -
This device allows one or more lamps to illuminate at sunset and turn off at dawn. Q1 and Q2 form a trigger device for the SCR, providing short pulses at 100Hz frequency. Pulse duration is set by R2 and C1... -
This circuit adopts the rather unusual Bowes/White emitter coupled multivibrator circuit. The oscillation frequency is about 1Hz and is set by C1 value. The LED starts flashing when the photo resistor is scarcely illuminated. The onset of flashing can be set.... -
The following is a method to allow day and night detection using Infrared/Visible light sensitive phototransistors and a simple LM339 voltage comparator circuit... -
Variable resistor R1 adjusts the light threshold at which the circuit triggers. R1`s value is chosen to match the photocells resistance at darkness. The circuit uses a CMOS 4001 IC. Gate U1a acts as the trigger, U1b and c form a latch. S1 resets the circuit..... -
This train detector makes use of hand held laser pointer devices that are widely available to detect trains over long distances... -
This page presents information on infrared - `Across The Track` train detection circuits. The circuits are designed around the LM339 comparator chip and can use a wide assortment of matched infrared - emitter / detector pairs... -
This page features basic, visible light photo-detector circuits that can be used to detect trains. These methods would normally be used with the photo sensor mounted between the rails... -
When the phototransistor is stroken by IR light it conducts and the voltage between the 1Mohm resistor(arbitrary) and the phototrans drops from VCC to lower values. When the voltage drops lower than VCC/3 the 555 is triggered and goes high (from 0 TO VCC)..... -
The output of the amplifier is to be measured on a digital voltmeter. Besides being able to accept 20 na to 200 micro amps and output voltages that range form 100 mv to 2 or 3 volts, the amplifier needed to have a low input resistance so the diode could be.... -
When the phototransistor is stroken by IR light it conducts and the voltage between the 1Mohm resistor(arbitrary) and the phototrans drops from VCC to lower values. When the voltage drops lower than VCC/3 the 555 is triggered and goes high (from 0 TO VCC)..... -
The Visual Target Tracking System (VTTS) is a system for visually tracking targets using a gimbal mounted camera and digital control circuitry. A small black and white camera is mounted on a stand that can be moved with two directions of freedom. When an....
New Circuits
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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.....
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