Light Laser LED Circuits
- Page 4
-
The circuit shows a simplex fiber link between the NE5080 transmitter and the NE5081 receiver. The components shown are for a center frequency of 5 MHz, although this frequency can be increased to 20 MHz with proper selection of external component values.....
-
-
This two-chip receiver with minimum external component count has been designed for low-cost fiber optic applications to 100-M baud (50 MHz). The receiver is divided into pre-and postamplifier !Cs for increased stability. The preamplifier IC features low....
-
The optical signal is coupled to the pin diode. Current flowing in the diode also flows into the input of the NE5211 preamplifier. The preamplifier is a fixed-gain block that has a 28-K!J differential transimpedance and does a single-ended to differential....
-
When power is first turned on, two of the LEDs are on and the other two remain off until the timing cycle reverses. The LEDs flash in pairs, but by pressing and holding Sl closed until only one of the LEDs is on, and then releasing it, the four LEDs can be....
-
Inserting two 1-MO resistors, R1 and R2, in the output stage of one of the circuit"s inverters limits the current needed by the oscillator tone more than a few pA. This circuit includes a CD4007 package, which has three CMOS inverters. It forms a standard....
-
The timing components are Rl, R2, and C,. Cl is a bypass capacitor used to reduce the effects of noise. At start-up, the voltage across C, is less than the trigger level voltage (1/3 Vnn). causing the timer to be triggered via pin 2. The output of the....
-
Uses a low cost CMOS IC to tum four LEDs on and off at a rate that is set by the values of R1, R2, Cl, and C2. The pulse rate for the component values given for R1 and R2 is about one cycle every four seconds. By lowering the values of Rl and R2 to 220 KO,....
-
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 indicator is basically a switch with hysteresis characteristics. If the input voltage momentarily (or permanently) exceeds the most positive reference level, LEDl is switched on. If, on the other hand, the voltage falls below the negative, or least....
-
Although theIR region is free from radio interference, it is subject to interference from incandescent lamps, fluorescent lamps, stray reflections, and other sources. A simple way to overcome that problem is to create a carrier by chopping the IR radiation....
-
When long ranges must be worked with IR light sources, and when high system reliability is required, pulsed-mode operation of the IRis required. Additional reliability of operation is attained by synchronously detecting the photodetector current, as this....
-
Infrared emissions detected by Ql are fed through Ula to Ulb, which amplifies the signal by a factor of 100. The amplified output ofUlb is fed to Ulc through R9, C2, and R6. Potentiometer R9 serves as a volume control. With R9 set to pass the maximum....
-
The transmitter consists of an oscillator which drives a high output IR emitting diode. The oscillator is a sJire start multivibrator circuit that provides an output of 15 to 1000 mark to space ratio at a frequency of 1 kHz. This large mark to space ratio....
-
Gates U1a and U1b are configured as a low-frequency oscillator. The output waveform at pin 11 is nonsymmetrical with the positive portion of the signal, making up only 20% of the time period. Diode D1, a 1N914 general-purpose unit, together with C1, R1,....
-
This simple IR detector turns on a real LED when Q2 is exposed to invisible IR radiation found in fiber-optics systems, position sensors, and TV remote-control units. The device can be built on top of a 9V battery and held in place with RTV. Its power....
-
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 zener provides a constant voltage of 20 V to unijunction transistor Ql, except at the end of each half-cycle of the input when the line voltage drops to zero. Initially, the voltage across capacitor Cl is zero and capacitor C2 cannot charge to trigger....
-
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....
-
This circuit has been designed to drive an 8-W fluorescent lamp from a 12-V source using an inexpensive inverter based on the ZTX652 transistor. The inverter will operate from supplies in the range of 10 to 16.5 V, thus making it suitable for use in....
-
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....
-
-
Ql and Q2 switch the primary windings of transformer Tl via a square wave at a frequency determined by its magnetic properties. Diodes Dl and D2 provide base return paths for the feedback current of Ql and Q2. The output winding of T1 is connected to a....
-
The laser diode·pulser is a simple drive circuit capable of driving the laser diode with 10-A, 20-ns pulses. For a 0.1 % duty cycle, the repetition rate will be 50 kHz. A complementary emitter follower is used as a driver. Switching speed is determined by....
-
The ·circuit includes a peak detector that irrunediately drives the readout to any new higher signal level and slowly lowers it after the signal drops to zero. The readout is a moving dot or expanding bar display. The circuit can be expanded for a longer....
-
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....
-
A resonance-tuned narrow-band amplifier reduces this optical object detector"s sensitivity to stray light. C1 and L1 in IC2A"s feedback loop cause tbe op amp to pass only those frequencies at or near the LED"s 5-kHz modulation rate. ..
-
A common method of transforming the output current of a photodiode into a voltage signal, paralleling the photodiode with a high-value load resistor, produces a nonlinear response. Also the combination of the load"s transresistance, Rr. and the....
-
In this strobe-light, two circuits are needed; one circuit charges a capacitor placing 320 V de between the cathode and anode of the flashtube. The other circuit provides bursts of approximately 4000 V to trigger the flashtube into conduction. The....
The circuit shows a simplex fiber link between the NE5080 transmitter and the NE5081 receiver. The components shown are for a center frequency of 5 MHz, although this frequency can be increased to 20 MHz with proper selection of external component values.....
This two-chip receiver with minimum external component count has been designed for low-cost fiber optic applications to 100-M baud (50 MHz). The receiver is divided into pre-and postamplifier !Cs for increased stability. The preamplifier IC features low....
The optical signal is coupled to the pin diode. Current flowing in the diode also flows into the input of the NE5211 preamplifier. The preamplifier is a fixed-gain block that has a 28-K!J differential transimpedance and does a single-ended to differential....
When power is first turned on, two of the LEDs are on and the other two remain off until the timing cycle reverses. The LEDs flash in pairs, but by pressing and holding Sl closed until only one of the LEDs is on, and then releasing it, the four LEDs can be....
Inserting two 1-MO resistors, R1 and R2, in the output stage of one of the circuit"s inverters limits the current needed by the oscillator tone more than a few pA. This circuit includes a CD4007 package, which has three CMOS inverters. It forms a standard....
The timing components are Rl, R2, and C,. Cl is a bypass capacitor used to reduce the effects of noise. At start-up, the voltage across C, is less than the trigger level voltage (1/3 Vnn). causing the timer to be triggered via pin 2. The output of the....
Uses a low cost CMOS IC to tum four LEDs on and off at a rate that is set by the values of R1, R2, Cl, and C2. The pulse rate for the component values given for R1 and R2 is about one cycle every four seconds. By lowering the values of Rl and R2 to 220 KO,....
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 indicator is basically a switch with hysteresis characteristics. If the input voltage momentarily (or permanently) exceeds the most positive reference level, LEDl is switched on. If, on the other hand, the voltage falls below the negative, or least....
Although theIR region is free from radio interference, it is subject to interference from incandescent lamps, fluorescent lamps, stray reflections, and other sources. A simple way to overcome that problem is to create a carrier by chopping the IR radiation....
When long ranges must be worked with IR light sources, and when high system reliability is required, pulsed-mode operation of the IRis required. Additional reliability of operation is attained by synchronously detecting the photodetector current, as this....
Infrared emissions detected by Ql are fed through Ula to Ulb, which amplifies the signal by a factor of 100. The amplified output ofUlb is fed to Ulc through R9, C2, and R6. Potentiometer R9 serves as a volume control. With R9 set to pass the maximum....
The transmitter consists of an oscillator which drives a high output IR emitting diode. The oscillator is a sJire start multivibrator circuit that provides an output of 15 to 1000 mark to space ratio at a frequency of 1 kHz. This large mark to space ratio....
Gates U1a and U1b are configured as a low-frequency oscillator. The output waveform at pin 11 is nonsymmetrical with the positive portion of the signal, making up only 20% of the time period. Diode D1, a 1N914 general-purpose unit, together with C1, R1,....
This simple IR detector turns on a real LED when Q2 is exposed to invisible IR radiation found in fiber-optics systems, position sensors, and TV remote-control units. The device can be built on top of a 9V battery and held in place with RTV. Its power....
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 zener provides a constant voltage of 20 V to unijunction transistor Ql, except at the end of each half-cycle of the input when the line voltage drops to zero. Initially, the voltage across capacitor Cl is zero and capacitor C2 cannot charge to trigger....
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....
This circuit has been designed to drive an 8-W fluorescent lamp from a 12-V source using an inexpensive inverter based on the ZTX652 transistor. The inverter will operate from supplies in the range of 10 to 16.5 V, thus making it suitable for use in....
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....
Ql and Q2 switch the primary windings of transformer Tl via a square wave at a frequency determined by its magnetic properties. Diodes Dl and D2 provide base return paths for the feedback current of Ql and Q2. The output winding of T1 is connected to a....
The laser diode·pulser is a simple drive circuit capable of driving the laser diode with 10-A, 20-ns pulses. For a 0.1 % duty cycle, the repetition rate will be 50 kHz. A complementary emitter follower is used as a driver. Switching speed is determined by....
The ·circuit includes a peak detector that irrunediately drives the readout to any new higher signal level and slowly lowers it after the signal drops to zero. The readout is a moving dot or expanding bar display. The circuit can be expanded for a longer....
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....
A resonance-tuned narrow-band amplifier reduces this optical object detector"s sensitivity to stray light. C1 and L1 in IC2A"s feedback loop cause tbe op amp to pass only those frequencies at or near the LED"s 5-kHz modulation rate. ..
A common method of transforming the output current of a photodiode into a voltage signal, paralleling the photodiode with a high-value load resistor, produces a nonlinear response. Also the combination of the load"s transresistance, Rr. and the....
In this strobe-light, two circuits are needed; one circuit charges a capacitor placing 320 V de between the cathode and anode of the flashtube. The other circuit provides bursts of approximately 4000 V to trigger the flashtube into conduction. The....
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.....
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to....
