Top Circuits Page 256
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Measuring range: room temperature is -10 ~ 40 ?; body temperature is 36 ~ 41 ?; Resolution: room temperature is 0.5 ?, body temperature is 0.05 ?; error: room temperature <1 ?, body temperature <0.1 ?. When S1 is in position 1, it shows the room temperature....
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The three-tone electronic doorbell circuit consists of buttons Sl-S3, transistors Vl, V2, speaker BL, resistors Rl-R3, capacitors Cl, C2, diode VD and battery GB, and it is shown in Figure 3-109. Rl-R3 use the 1/4W carbon film resistors or metal film....
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The three-tone electronic doorbell circuit consists of the coding triggered circuit, multi-tone generator and audio amplifier circuit, and it is shown in Figure 3-110. Coding trigger circuit is composed of the buttons Sl-S6, two four-input AND gate (DI, D2)....
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Touching eight-sound five-flash dynamic toy circuit diagram is shown in the diagram. It consists of HFC3018 module, and it can generate eight kinds ofdifferent voices: like step gunfire, aviation gunfire, game sight, telephone sight, bomb 1, bomb 2 sound,....
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The two-tone electronic doorbell circuit is composed of the input trigger circuit and audio output circuit, ans it is shown in Figure 3-107. The input trigger circuit is composed of the doorbell button S, transistor V1, resistors Rl-R3, capacitor Cl and dual....
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The two-tone electronic doorbell circuit is composed of the trigger control circuit and doorbell generating circuit, and it is shown in Figure 3-108. Trigger control circuit consists of doorbell button S, resistors Rl-R3, electrical wear devices Cl-C3,....
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Transmitter: Pressing the SB will make the transmitter circuit work. D1, D2 and R2, R3, C4 constitute a low-frequency oscillator to control the audio oscillator composed of the D3, D4 and D5, D6, then it works alternately. The generated audio signal is added....
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In order to remove circulating current of zero-voltage switch three-level DC converter in zero state, we come up with kind of zero-voltage zero-current switch three-level DC converter circuit. The circuit is shown in the following diagram 1, the main....
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Withthe 1.5V battery supply power, The Integrated circuit LM3909 can drive the light emitting diode NSL5027. The 300uF electrolytic capacitor is circumscribed capacitor? which makes the flash speed limit around 1Hz....
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A few months ago Milardo starting to study the 8051 Microcontroller. From his research Miardo has designed a new circuit and called it 3-Digit Display Scoreboard with 4x4 Keypad Matrix....
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This discussion covers 3 different Xenon flashing circuits from disposable cameras. From them, you will learn circuit tricks that have NEVER been shown in any theory book.The first circuit covers 6 BUILDING BLOCKS.You will need an old disposable Flash Camera....
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When the circuit is connected to the hi-fi equipment or at both ends of the electronic instruments speaker, the audio level can be modulated to 500W lamp by proportion. Using 3 appropriate sets of audio filters and 3 different color light Union microscopy to....
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The chart shows the Christmas lights circuit which uses simple, inexpensive CD4069 CMOS hex inverter to control four circuits with 200 light-emitting diodes (each circuit has 50 LEDs), and it is directly supplied by the 220V power source without power....
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Four-wire ballast connection of fluorescent There are four lead wires in four-wire ballast, including main and auxiliary coils. The connection of two lead wires in main coil is the same with second-line ballast, both of them connect between the lamp and....
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This circuit takes signal (doppler) from a radar,un, amplifies and limits it, and feeds the frequency into a counter (U4) and display circuit (DISP1, DISP2,U5,U6). Counter calibration is set by clock circuit U2B. Calibration is obtained via R21 and R22. R21....
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This solar birdhouse light is an economical circuit of a mini solar lighting system circuit is presented here. At the heart of the circuit is a mini 6V/2W solar panel. Here, this solar panel is used to charge a 4V/800mAh rechargeable battery through a charge....
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This bicycle safety flashing light system is based on a newly invented electrical generating system, NO battery needed, No friction on any parts of the bicycle. No drag. get the energy almost free (at least on bicycle). Very bright. Standby light....
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General connection method of fluorescent lamp Fluorescent lamps used in homes and public places lighting and so on, with luminous efficiency, long service life, Figure 20 is the general wiring diagram for lamp. Fluorescent working principle: When the switch....
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Homemade 20W fluorescent lamp dimmer Using the method of connecting capacitor in series can easily control the brightness of fluorescent lamps. To adapt to different lighting requirements. Figure 28 is a modified circuit diagram. When the switch connects to....
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Figure A shows the circuit of a direct-trigger timing light. The trigger voltage is taken from the car`s ignition circuit by a direct connection to a spark plug. A circuit using an inductive pickup is shown in Fig. B. A trigger transformer is used to develop....
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Is infrared emission circuit diagram. NE555 circuit generates a 40kHz pulse which is sent by the infrared emission control SE303 after beingamplified by VT. (b) is remote receiver and infrared dimming circuit composed of the KA2184. LS7232 is an integrated....
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The circuit is based on the grid-dip or absorption effect, which occurs when a parallel resonant circuit is coupled to an oscillator of the same frequency. Q1 operates in a conventional Colpitts oscillator circuit at a ftxed frequency of approximately 4 MHz.....
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MAX7316`s main technical characteristics are as follow. ? 400kbps, 2-wire Serial Interface, 5.5V voltage tolerance. ? working voltage is 2 ~ 3.6V. ? 8-bit PWM White LED brightness control, global brightness control 16 with additional 16 independent....
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Multiplexed display suitable for LED readouts is provided by circuit using TTL counters to count 60-Hz Iine.When count reaches o`clock, flip-flop M is set on evely cycle. Gate G3 then detects when time goes to 13 o`clock, and clears shift register.Carry....
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The circuit described here provides three channels of optically isolated input that will work for many precision signal-acquisition applications. The only power required is a single 15-V rail with ground common to the analog-to-digital converter. Multiplexer....
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This Outdoor LED Solar Garden Lights project is a hobby circuit of an automatic garden light using a LDR and 6V/5W solar panel. During day time, the internal rechargeable 6 Volt SLA battery receives charging current from the connected solar panel through....
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Used in multiplier that acts with one of operational amplifiers of analog computer. Double-triode V1 here provides pulse-amplitude modulation, for use with separate pulse-width modulator to form desired product of two input variables.-A. J. Ferraro,....
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As shown in the diagram above, it is a radio remote control dimmer circuit. The radio remote control dimmer circuit adopts micro radio transmit/receive module and light modulation ASIC. So the circuit is concise and easy to produce. It works reliably. And....
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Simple silicon-controlled dimmer As shown in Figure 13, it is a simple circuit of SCR dimming lights. The w resistance in the potentiometer decreases, SCR conduction angle increases, the light`s intensity increases, the resistance enlarges, the SCR....
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This circuitry zooms in magnification of 1200000 times, the bandwidth is 0.5~14 Mhzs, the input impedance is 700 ?, the output impedance is 35 ?(to measure in the 5 MHZ), the output level of noise is 0.6~0.8 V. In the chart, T1 and T2 are direct coupling....
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This simple circuit shown int the schematic diagram actives the switch using sound. We can use this circuit for various applications, such as automatic (sound-controlled) disco light or car s LED light show. The Q1 amplify the audio from mic. The R1 is used....
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In order to solve the lag and light transition phenomena, it can use the Triac dimming light circuit shown in the figure with dual time constant. The circuit increases R3, C2 resistor-capacitor network, and the reducing charge on capacitor C1 can get....
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The diagram shows telephone control automatic lighting circuit. At night, when telephone rings or master takes up telephone transmitter dialing, the light can lighten; when telephone ringer stopped (no one listen) or on-hook, it can delay 10~40s, then the....
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The fluorescent with reactive power compensation As ballast is an inductive load. It needs to consume some reactive power, causing the power factor of fluorescent lamp decreases. It affects the ability of full-powered devices, and reduces the voltage of....
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As shown in the figure, it isa sensing automatically lightmade by newHN911L pyroelectric infrared detection module. The HN911L integrates high - sensitivity infrared sensors, PIR, amplifiers, signal processing circuit andoutput circuit. Itisable to remote....
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Portable counter is designed with low-power logic to minimize battery drain, yet provides good performance.Since most of milliwatt power drain is taken by digital readout, circuit blanks out LED display when there is no input signal. Time base divides 1-MHz....
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The circuit shown is a simple digital frequency meter, which indicates the frequency in hertz of an astable 555 timer. It could, perhaps, be adapted for other uses. An NPN transistor, TR2, is connected to the 555 astable to be measured, as shown in the....
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The figures(a), (b) are as shown, they are AC measuring circuits. The 21(a) is a current measuring schematic diagram of magnetic balanced mode Hall device. If the magnetic field produced by the measured current IN is B1, then B1 will produce Hall voltage. If....
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This 1-kHz linear-scale analog frequency meter circuit uses the 555 as a pulse counter. Frequency is read on M1, (or 1 mA meter) which can be calibrated to read 0 to 1 kHz....
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Synchronous clock signal is input to a cascade of timer circuit composed of two LM122H, then the synchronization clock is converted to the desired width of the pulse (Fig. 10?s) which will be add to LF198 LOGIC end (8 feet) as the sampling and holding....
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Working principle: Two pairs of photoelectric detection devices are installed in the access channel. On one side the light source A (transmitter) and the photoresistor LDR1 (receiver) are installed in the entrance of the channel; on the other side, the light....
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The circuit is shown in Figure, which consists of capacitance three-point oscillator, isolation level, voltage doubler rectifier circuit and stereo sound circuit and flash display circuit. It can detect the crystal`s goodness or badness, good crystal will....
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The circuit can measure the frequency between 1. 5kHz ~ 500kHz by connecting C1 ~ C6 different capacitors. The maximum frequency is up to 1MHz. Transistor T1 can be used as the integrator, and its load resistor is 15k © resistor and R1 ~~ R6 adjustable....
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The proximity detector senses the passing of the PC board pieces as the wheel rotates, providing an output signal, which has a clean transition between high and low voltage levels, and is ideal for triggering counting or processing circuits. Next is the....
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Ball game scoring device s circuit is as shown in the picture. It is used to record and display the performance of a ball game. The first Nixie tube has only two states, that is extinguishing or displaying 1; the next two Nixie tube can display ten states....
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The bearing fault detector circuit is composed of the bearing detection sensor, signal processing circuit, transistor V, audio amplifier integrated circuit IC2, speaker BL and the RC element, and IC1, light-emitting diode VL, transistor are shown as the....
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This circuit has a focused optical sensor to transmit light to the CO reagent, and then sense the amount of light reflected. The reagent for CO detection darkens from a light yellow color when exposed to CO. According to the card`s manufacturer, a....
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The above picture is audio logic level probe circuit, which is composed of voltage comparator, multivibrator, and piezoelectric ceramics HTD etc. The latter two constitute audio circuit and the audio frequency is used to assess the TTL or COMOS instrument s....
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A Coil Coupled Operation Metal Detector made from readily obtainable components and using an ordinary medium receiver as a detector....
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DC capacitor tester circuit diagram composed of 555 is shown as the chart. The tester is composed of the pulse generator, one-shot, DC amplifier and meter indication circuit. It can measures the npF ~ 10?F capacitor. The range is divided into 0 ~ 100PF, 0 ~....
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A basic digital voltmeter circuit using the Harris Semiconductor ICL7107 is shown. It has a 2-V range. Calibration consists of applying a known voltage of 1.2 V to the input and adjusting R3 for a correct reading on the display. Supply is ±5 V, and S1....
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The monitor senses an ajar door and, if the situation isn`t corrected within 20 seconds, sounds a beeping alarm. The circuit is controlled by a magnetic reed switch and magnet on the door. With the door closed, the switch is closed and the alarm is disarmed.....
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Displays up to eight different DC voltages on CRT terminal of microprocessor under key-board control, using BASIC commands and BASIC routine given in article. Uses Motorola MC14433 modified dual-lamp integrating analog-to-digital converter. Unknown voltage....
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Capacitor instrument is not to be used to measure the capacity of the capacitor but for identifing good or bad and short circuit or open circuit, then it provides a reliable quality assurance for the production of circuit to reduce the circuit making....
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Game-scoring display screen circuit diagram is shown as in the above picture. The circuit is composed of add/subtract scoring input circuit, add/subtract scoring circuit, counting - decoding display circuit and reset circuit....
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The circuit uses a Hall-effect sensor, which consists of an IC that resides in a small gap in a flux-collector toroid, to measure dc current from 1 to 40 A. Wrap the current-carrying wire through the toroid; the Hall voltage VH is then linearly proportional....
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This homemade metal detector circuit will help you find objects composed of materials with relatively high magnetic permeability. It is not suitable for buried coins discovery that is not sensitive enough but you can detect pirates treasures! The metal....
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The circuit is based on an LM3914N bar graph display driver device (IC1), which can be used to drive up to ten LEDs. This is connected so that with OV12 at the input only the first LED indicator switches on. This simple peak reading VU meter circuit uses six....
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This battery-powered metal detector uses four exclusive-OR gates contained in the 4030 CMOS integrated circuit. The gates are wired as a twin-oscillators and a search coil serves as the inductance element in one of the oscillators. When the coil is brought....
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This circuit canbeused for detecting infrared light, for example, it is used for detecting infrared band light signal in spectrophotometer. Amplifier output voltage Vo=Is·Rd·Rf/Ri wherein : Is-signal current; Rd-optical detector essential resistance Dector....
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The heart of the motion detector movement detection circuit is motion detection chip IC1 (KC778B). The signal frequency from PIR sensor is low (0.1Hz ~ 10Hz) while the band is very wide, the chip will optimize it. The working voltage of KC778B is 4V ~ 15V,....
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As is shown in the picture, the Pulse Demodulator is composed by CMOS Hex Inverter. This circuit can be used to process envelop detection on Amplitude Pulse....
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Here is one basic circuit of a simple but accurate 1Hz timebase generator built around a standard Quartz clock circuit board. Just lift the clock PCB from any cheap quartz clock and carefully remove all extra components like the drive coil, buzzer, alarm....
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The RF modulator is the very important component in TV, VCR, satellite receiver, format converter, home computer and game machine. This circuit is simple, stable and easy to make, it can be easily connected with a lot kinds of circuit boards. The figure is....
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Reaction Capability Tester is used to test and train man s quick-response capability. It has various type of construction and the Reaction Capability Tester as shown in the picture is composed of decimal counter CD4017 and luminous diode. The construction of....
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This figure shows the schematic diagram of the simple inductance meter. U1, a 74LS00 two-input quad NAND gate logic integrated circuit, two resistors, a capacitor, and a surplus microprocessor crystal form a stable crystal oscillator near the marked....
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Switching of feedback resistors for opamp driven by Radio Shack 276-115 selenium solar cell gives multirange linear light meter. With 1000-megohm resistor for highest sensitivity, star Sirius will produce pho-tocurrent of about 25 pA when aolar cell is....
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Because of the transmitter circuit of the inductive headphone must installed on the room wall or on the ceiling, so the inductive headphone can not be used outdoor, this is the main weak point of the inductive headphone. But the infrared rays wireless....
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This metal detector circuit needs to be powered using a 9 volts power supply ( DC) or a 9 volts battery. The C1 capacitor is a variable capacitor with a value of 365 pF, C2 is a 100pF silver mica capacitor, C3 is a 0.05 uF disc capacitor and the C4 is a 4.7....
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In the figure is the 567 FM demodulator circuit. In the figure, the FM signal is input from 3-pin and the demodulated signal is output from 5-pin. The central frequency of the FM signal that the circuit can demodulate is: fo=1.1/RC. In the circuit, C1 is the....
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By the dual sound multi-frequency encoding signal, the circuit modulates the emitted carrier frequency, and it composes a DTMF encoding wireless calling system circuit. The circuit uses DTMF encoding circuit UM97085 and decoding circuit YN9101 to form a....
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In the figure is the bilateral band modem circuit composed of NE561B. The loading frequency of the input modulating signal is f0=1MHz. When the AM modulation signal is added on the input terminal of the multiplier, it is also added on the phase detection....
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The thermistor RT and R1, R2, R3 and RP1 form a temperature measurement bridge. When temperature is at 20 ?, using R1, R3 and adjusting RP1 can allow bridge to keep balance. When temperature rises, the resistance of the thermistor RT reduces, the bridge in....
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Plug the diode VD under test into sockets X1 and X2. Stabilized power supply adds reverse breakdown voltage to VD and the stabilized voltage value Uz can be read from voltage meter V, and the stable-working current value can be read from the milliammeter mA....
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Using an LM3915 VU meter LED bar graph driver?10 LEDs are driven?A simple audio amplifierdrives a detector circuit?which provides dc drive for the LM3915....
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This power supply based 7805 IC regulator, it can provides a regulated output voltage of between 5 V to 15 VDC, it is adjusted and set by a preset resistor. Maximum output current range of this power supply is 350 mA, its enough to supply powered calculator,....
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In the measurement of changed supply current, the return line of the power -side is grounded, sometimes it can not be connected to shunt resistor between the casing and the rack. INA168 is a current detecting circuit ASIC, the indicators are as following:....
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Consists essentially of 60-Hz sine-wave oscillator with 10K frequency-control pot, two buffer stages, and push-pull power amplifier. Circuit eliminates noise problems of square-wave inverters when operating 115-V radio receiver or cassette player in car.- G.....
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The 7208 seven-stage decimal counter can be used as the frequency counter, it has the latch and multiplexing functions, and it has the direct digital driving circuit and the display driving circuit. 7207IC 6.5536MHZ crystal oscillator`s output frequency is....
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A schematic diagram of the high-voltage power supply recommended for use with the power transformer. This power supply can also be used for other equipment with similar requirements.CAUTION: hazardous high voltages....
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The constant current charging circuit which is composed of the three-port voltage stabilizer is as shown in figure 2-21. Because the electric potential difference of the LM317`s pin-1 and pin-2 is 1. 25V, if we ignore the shunting effects of R3, R1, LED, the....
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Here we introduce a kind of 30W micro switch regulated power supply composed of TOP224Y, its circuit is shown in the diagram. Its feature is using TL431 to replace regulation tube VDz2 in the sampling circuit. That is, it can reach the technical target of....
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This IF system uses a NE602 oscillator/mixer to convert VHF TV signals of 60 to 72 MHz (channe13 or channel4 under the U.S. NTSC) to 45 MHz. An SAW filter is used to provide bandpass filtering, followed by an LM1823 video IF/AGC/AFC/detector IC. Recovered....
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The input stage of this voltmeter circuit uses operational amplifier and diode feedback to form linearity peak value rectifier circuit. Through R2/R2 partial pressure isolation, it is sent to double multi-channel BCD output A/D converter CA3162E, it also can....
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An audio mixer is a handy circuit that will combine two or more audio signal sources into one signal channel. The figure shows an audio mixer that is built around the LM3900 CDA. The crux of this circuit is the three input networks, principally R3, R4, and....
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The aim of a DC power supply is to provide the required level of DC power to the load using an AC supply at the input. Different applications require different attributes, but more often than not these days DC power supplies provide an accurate output....
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Measuring range: room temperature is -10 ~ 40 ?; body temperature is 36 ~ 41 ?; Resolution: room temperature is 0.5 ?, body temperature is 0.05 ?; error: room temperature <1 ?, body temperature <0.1 ?. When S1 is in position 1, it shows the room temperature....
The three-tone electronic doorbell circuit consists of buttons Sl-S3, transistors Vl, V2, speaker BL, resistors Rl-R3, capacitors Cl, C2, diode VD and battery GB, and it is shown in Figure 3-109. Rl-R3 use the 1/4W carbon film resistors or metal film....
The three-tone electronic doorbell circuit consists of the coding triggered circuit, multi-tone generator and audio amplifier circuit, and it is shown in Figure 3-110. Coding trigger circuit is composed of the buttons Sl-S6, two four-input AND gate (DI, D2)....
Touching eight-sound five-flash dynamic toy circuit diagram is shown in the diagram. It consists of HFC3018 module, and it can generate eight kinds ofdifferent voices: like step gunfire, aviation gunfire, game sight, telephone sight, bomb 1, bomb 2 sound,....
The two-tone electronic doorbell circuit is composed of the input trigger circuit and audio output circuit, ans it is shown in Figure 3-107. The input trigger circuit is composed of the doorbell button S, transistor V1, resistors Rl-R3, capacitor Cl and dual....
The two-tone electronic doorbell circuit is composed of the trigger control circuit and doorbell generating circuit, and it is shown in Figure 3-108. Trigger control circuit consists of doorbell button S, resistors Rl-R3, electrical wear devices Cl-C3,....
Transmitter: Pressing the SB will make the transmitter circuit work. D1, D2 and R2, R3, C4 constitute a low-frequency oscillator to control the audio oscillator composed of the D3, D4 and D5, D6, then it works alternately. The generated audio signal is added....
In order to remove circulating current of zero-voltage switch three-level DC converter in zero state, we come up with kind of zero-voltage zero-current switch three-level DC converter circuit. The circuit is shown in the following diagram 1, the main....
Withthe 1.5V battery supply power, The Integrated circuit LM3909 can drive the light emitting diode NSL5027. The 300uF electrolytic capacitor is circumscribed capacitor? which makes the flash speed limit around 1Hz....
A few months ago Milardo starting to study the 8051 Microcontroller. From his research Miardo has designed a new circuit and called it 3-Digit Display Scoreboard with 4x4 Keypad Matrix....
This discussion covers 3 different Xenon flashing circuits from disposable cameras. From them, you will learn circuit tricks that have NEVER been shown in any theory book.The first circuit covers 6 BUILDING BLOCKS.You will need an old disposable Flash Camera....
When the circuit is connected to the hi-fi equipment or at both ends of the electronic instruments speaker, the audio level can be modulated to 500W lamp by proportion. Using 3 appropriate sets of audio filters and 3 different color light Union microscopy to....
The chart shows the Christmas lights circuit which uses simple, inexpensive CD4069 CMOS hex inverter to control four circuits with 200 light-emitting diodes (each circuit has 50 LEDs), and it is directly supplied by the 220V power source without power....
Four-wire ballast connection of fluorescent There are four lead wires in four-wire ballast, including main and auxiliary coils. The connection of two lead wires in main coil is the same with second-line ballast, both of them connect between the lamp and....
This circuit takes signal (doppler) from a radar,un, amplifies and limits it, and feeds the frequency into a counter (U4) and display circuit (DISP1, DISP2,U5,U6). Counter calibration is set by clock circuit U2B. Calibration is obtained via R21 and R22. R21....
This solar birdhouse light is an economical circuit of a mini solar lighting system circuit is presented here. At the heart of the circuit is a mini 6V/2W solar panel. Here, this solar panel is used to charge a 4V/800mAh rechargeable battery through a charge....
This bicycle safety flashing light system is based on a newly invented electrical generating system, NO battery needed, No friction on any parts of the bicycle. No drag. get the energy almost free (at least on bicycle). Very bright. Standby light....
General connection method of fluorescent lamp Fluorescent lamps used in homes and public places lighting and so on, with luminous efficiency, long service life, Figure 20 is the general wiring diagram for lamp. Fluorescent working principle: When the switch....
Homemade 20W fluorescent lamp dimmer Using the method of connecting capacitor in series can easily control the brightness of fluorescent lamps. To adapt to different lighting requirements. Figure 28 is a modified circuit diagram. When the switch connects to....
Figure A shows the circuit of a direct-trigger timing light. The trigger voltage is taken from the car`s ignition circuit by a direct connection to a spark plug. A circuit using an inductive pickup is shown in Fig. B. A trigger transformer is used to develop....
Is infrared emission circuit diagram. NE555 circuit generates a 40kHz pulse which is sent by the infrared emission control SE303 after beingamplified by VT. (b) is remote receiver and infrared dimming circuit composed of the KA2184. LS7232 is an integrated....
The circuit is based on the grid-dip or absorption effect, which occurs when a parallel resonant circuit is coupled to an oscillator of the same frequency. Q1 operates in a conventional Colpitts oscillator circuit at a ftxed frequency of approximately 4 MHz.....
MAX7316`s main technical characteristics are as follow. ? 400kbps, 2-wire Serial Interface, 5.5V voltage tolerance. ? working voltage is 2 ~ 3.6V. ? 8-bit PWM White LED brightness control, global brightness control 16 with additional 16 independent....
Multiplexed display suitable for LED readouts is provided by circuit using TTL counters to count 60-Hz Iine.When count reaches o`clock, flip-flop M is set on evely cycle. Gate G3 then detects when time goes to 13 o`clock, and clears shift register.Carry....
The circuit described here provides three channels of optically isolated input that will work for many precision signal-acquisition applications. The only power required is a single 15-V rail with ground common to the analog-to-digital converter. Multiplexer....
This Outdoor LED Solar Garden Lights project is a hobby circuit of an automatic garden light using a LDR and 6V/5W solar panel. During day time, the internal rechargeable 6 Volt SLA battery receives charging current from the connected solar panel through....
Used in multiplier that acts with one of operational amplifiers of analog computer. Double-triode V1 here provides pulse-amplitude modulation, for use with separate pulse-width modulator to form desired product of two input variables.-A. J. Ferraro,....
As shown in the diagram above, it is a radio remote control dimmer circuit. The radio remote control dimmer circuit adopts micro radio transmit/receive module and light modulation ASIC. So the circuit is concise and easy to produce. It works reliably. And....
Simple silicon-controlled dimmer As shown in Figure 13, it is a simple circuit of SCR dimming lights. The w resistance in the potentiometer decreases, SCR conduction angle increases, the light`s intensity increases, the resistance enlarges, the SCR....
This circuitry zooms in magnification of 1200000 times, the bandwidth is 0.5~14 Mhzs, the input impedance is 700 ?, the output impedance is 35 ?(to measure in the 5 MHZ), the output level of noise is 0.6~0.8 V. In the chart, T1 and T2 are direct coupling....
This simple circuit shown int the schematic diagram actives the switch using sound. We can use this circuit for various applications, such as automatic (sound-controlled) disco light or car s LED light show. The Q1 amplify the audio from mic. The R1 is used....
In order to solve the lag and light transition phenomena, it can use the Triac dimming light circuit shown in the figure with dual time constant. The circuit increases R3, C2 resistor-capacitor network, and the reducing charge on capacitor C1 can get....
The diagram shows telephone control automatic lighting circuit. At night, when telephone rings or master takes up telephone transmitter dialing, the light can lighten; when telephone ringer stopped (no one listen) or on-hook, it can delay 10~40s, then the....
The fluorescent with reactive power compensation As ballast is an inductive load. It needs to consume some reactive power, causing the power factor of fluorescent lamp decreases. It affects the ability of full-powered devices, and reduces the voltage of....
As shown in the figure, it isa sensing automatically lightmade by newHN911L pyroelectric infrared detection module. The HN911L integrates high - sensitivity infrared sensors, PIR, amplifiers, signal processing circuit andoutput circuit. Itisable to remote....
Portable counter is designed with low-power logic to minimize battery drain, yet provides good performance.Since most of milliwatt power drain is taken by digital readout, circuit blanks out LED display when there is no input signal. Time base divides 1-MHz....
The circuit shown is a simple digital frequency meter, which indicates the frequency in hertz of an astable 555 timer. It could, perhaps, be adapted for other uses. An NPN transistor, TR2, is connected to the 555 astable to be measured, as shown in the....
The figures(a), (b) are as shown, they are AC measuring circuits. The 21(a) is a current measuring schematic diagram of magnetic balanced mode Hall device. If the magnetic field produced by the measured current IN is B1, then B1 will produce Hall voltage. If....
This 1-kHz linear-scale analog frequency meter circuit uses the 555 as a pulse counter. Frequency is read on M1, (or 1 mA meter) which can be calibrated to read 0 to 1 kHz....
Synchronous clock signal is input to a cascade of timer circuit composed of two LM122H, then the synchronization clock is converted to the desired width of the pulse (Fig. 10?s) which will be add to LF198 LOGIC end (8 feet) as the sampling and holding....
Working principle: Two pairs of photoelectric detection devices are installed in the access channel. On one side the light source A (transmitter) and the photoresistor LDR1 (receiver) are installed in the entrance of the channel; on the other side, the light....
The circuit is shown in Figure, which consists of capacitance three-point oscillator, isolation level, voltage doubler rectifier circuit and stereo sound circuit and flash display circuit. It can detect the crystal`s goodness or badness, good crystal will....
The circuit can measure the frequency between 1. 5kHz ~ 500kHz by connecting C1 ~ C6 different capacitors. The maximum frequency is up to 1MHz. Transistor T1 can be used as the integrator, and its load resistor is 15k © resistor and R1 ~~ R6 adjustable....
The proximity detector senses the passing of the PC board pieces as the wheel rotates, providing an output signal, which has a clean transition between high and low voltage levels, and is ideal for triggering counting or processing circuits. Next is the....
Ball game scoring device s circuit is as shown in the picture. It is used to record and display the performance of a ball game. The first Nixie tube has only two states, that is extinguishing or displaying 1; the next two Nixie tube can display ten states....
The bearing fault detector circuit is composed of the bearing detection sensor, signal processing circuit, transistor V, audio amplifier integrated circuit IC2, speaker BL and the RC element, and IC1, light-emitting diode VL, transistor are shown as the....
This circuit has a focused optical sensor to transmit light to the CO reagent, and then sense the amount of light reflected. The reagent for CO detection darkens from a light yellow color when exposed to CO. According to the card`s manufacturer, a....
The above picture is audio logic level probe circuit, which is composed of voltage comparator, multivibrator, and piezoelectric ceramics HTD etc. The latter two constitute audio circuit and the audio frequency is used to assess the TTL or COMOS instrument s....
A Coil Coupled Operation Metal Detector made from readily obtainable components and using an ordinary medium receiver as a detector....
DC capacitor tester circuit diagram composed of 555 is shown as the chart. The tester is composed of the pulse generator, one-shot, DC amplifier and meter indication circuit. It can measures the npF ~ 10?F capacitor. The range is divided into 0 ~ 100PF, 0 ~....
A basic digital voltmeter circuit using the Harris Semiconductor ICL7107 is shown. It has a 2-V range. Calibration consists of applying a known voltage of 1.2 V to the input and adjusting R3 for a correct reading on the display. Supply is ±5 V, and S1....
The monitor senses an ajar door and, if the situation isn`t corrected within 20 seconds, sounds a beeping alarm. The circuit is controlled by a magnetic reed switch and magnet on the door. With the door closed, the switch is closed and the alarm is disarmed.....
Displays up to eight different DC voltages on CRT terminal of microprocessor under key-board control, using BASIC commands and BASIC routine given in article. Uses Motorola MC14433 modified dual-lamp integrating analog-to-digital converter. Unknown voltage....
Capacitor instrument is not to be used to measure the capacity of the capacitor but for identifing good or bad and short circuit or open circuit, then it provides a reliable quality assurance for the production of circuit to reduce the circuit making....
Game-scoring display screen circuit diagram is shown as in the above picture. The circuit is composed of add/subtract scoring input circuit, add/subtract scoring circuit, counting - decoding display circuit and reset circuit....
The circuit uses a Hall-effect sensor, which consists of an IC that resides in a small gap in a flux-collector toroid, to measure dc current from 1 to 40 A. Wrap the current-carrying wire through the toroid; the Hall voltage VH is then linearly proportional....
This homemade metal detector circuit will help you find objects composed of materials with relatively high magnetic permeability. It is not suitable for buried coins discovery that is not sensitive enough but you can detect pirates treasures! The metal....
The circuit is based on an LM3914N bar graph display driver device (IC1), which can be used to drive up to ten LEDs. This is connected so that with OV12 at the input only the first LED indicator switches on. This simple peak reading VU meter circuit uses six....
This battery-powered metal detector uses four exclusive-OR gates contained in the 4030 CMOS integrated circuit. The gates are wired as a twin-oscillators and a search coil serves as the inductance element in one of the oscillators. When the coil is brought....
This circuit canbeused for detecting infrared light, for example, it is used for detecting infrared band light signal in spectrophotometer. Amplifier output voltage Vo=Is·Rd·Rf/Ri wherein : Is-signal current; Rd-optical detector essential resistance Dector....
The heart of the motion detector movement detection circuit is motion detection chip IC1 (KC778B). The signal frequency from PIR sensor is low (0.1Hz ~ 10Hz) while the band is very wide, the chip will optimize it. The working voltage of KC778B is 4V ~ 15V,....
As is shown in the picture, the Pulse Demodulator is composed by CMOS Hex Inverter. This circuit can be used to process envelop detection on Amplitude Pulse....
Here is one basic circuit of a simple but accurate 1Hz timebase generator built around a standard Quartz clock circuit board. Just lift the clock PCB from any cheap quartz clock and carefully remove all extra components like the drive coil, buzzer, alarm....
The RF modulator is the very important component in TV, VCR, satellite receiver, format converter, home computer and game machine. This circuit is simple, stable and easy to make, it can be easily connected with a lot kinds of circuit boards. The figure is....
Reaction Capability Tester is used to test and train man s quick-response capability. It has various type of construction and the Reaction Capability Tester as shown in the picture is composed of decimal counter CD4017 and luminous diode. The construction of....
This figure shows the schematic diagram of the simple inductance meter. U1, a 74LS00 two-input quad NAND gate logic integrated circuit, two resistors, a capacitor, and a surplus microprocessor crystal form a stable crystal oscillator near the marked....
Switching of feedback resistors for opamp driven by Radio Shack 276-115 selenium solar cell gives multirange linear light meter. With 1000-megohm resistor for highest sensitivity, star Sirius will produce pho-tocurrent of about 25 pA when aolar cell is....
Because of the transmitter circuit of the inductive headphone must installed on the room wall or on the ceiling, so the inductive headphone can not be used outdoor, this is the main weak point of the inductive headphone. But the infrared rays wireless....
This metal detector circuit needs to be powered using a 9 volts power supply ( DC) or a 9 volts battery. The C1 capacitor is a variable capacitor with a value of 365 pF, C2 is a 100pF silver mica capacitor, C3 is a 0.05 uF disc capacitor and the C4 is a 4.7....
In the figure is the 567 FM demodulator circuit. In the figure, the FM signal is input from 3-pin and the demodulated signal is output from 5-pin. The central frequency of the FM signal that the circuit can demodulate is: fo=1.1/RC. In the circuit, C1 is the....
By the dual sound multi-frequency encoding signal, the circuit modulates the emitted carrier frequency, and it composes a DTMF encoding wireless calling system circuit. The circuit uses DTMF encoding circuit UM97085 and decoding circuit YN9101 to form a....
In the figure is the bilateral band modem circuit composed of NE561B. The loading frequency of the input modulating signal is f0=1MHz. When the AM modulation signal is added on the input terminal of the multiplier, it is also added on the phase detection....
The thermistor RT and R1, R2, R3 and RP1 form a temperature measurement bridge. When temperature is at 20 ?, using R1, R3 and adjusting RP1 can allow bridge to keep balance. When temperature rises, the resistance of the thermistor RT reduces, the bridge in....
Plug the diode VD under test into sockets X1 and X2. Stabilized power supply adds reverse breakdown voltage to VD and the stabilized voltage value Uz can be read from voltage meter V, and the stable-working current value can be read from the milliammeter mA....
Using an LM3915 VU meter LED bar graph driver?10 LEDs are driven?A simple audio amplifierdrives a detector circuit?which provides dc drive for the LM3915....
This power supply based 7805 IC regulator, it can provides a regulated output voltage of between 5 V to 15 VDC, it is adjusted and set by a preset resistor. Maximum output current range of this power supply is 350 mA, its enough to supply powered calculator,....
In the measurement of changed supply current, the return line of the power -side is grounded, sometimes it can not be connected to shunt resistor between the casing and the rack. INA168 is a current detecting circuit ASIC, the indicators are as following:....
Consists essentially of 60-Hz sine-wave oscillator with 10K frequency-control pot, two buffer stages, and push-pull power amplifier. Circuit eliminates noise problems of square-wave inverters when operating 115-V radio receiver or cassette player in car.- G.....
The 7208 seven-stage decimal counter can be used as the frequency counter, it has the latch and multiplexing functions, and it has the direct digital driving circuit and the display driving circuit. 7207IC 6.5536MHZ crystal oscillator`s output frequency is....
A schematic diagram of the high-voltage power supply recommended for use with the power transformer. This power supply can also be used for other equipment with similar requirements.CAUTION: hazardous high voltages....
The constant current charging circuit which is composed of the three-port voltage stabilizer is as shown in figure 2-21. Because the electric potential difference of the LM317`s pin-1 and pin-2 is 1. 25V, if we ignore the shunting effects of R3, R1, LED, the....
Here we introduce a kind of 30W micro switch regulated power supply composed of TOP224Y, its circuit is shown in the diagram. Its feature is using TL431 to replace regulation tube VDz2 in the sampling circuit. That is, it can reach the technical target of....
This IF system uses a NE602 oscillator/mixer to convert VHF TV signals of 60 to 72 MHz (channe13 or channel4 under the U.S. NTSC) to 45 MHz. An SAW filter is used to provide bandpass filtering, followed by an LM1823 video IF/AGC/AFC/detector IC. Recovered....
The input stage of this voltmeter circuit uses operational amplifier and diode feedback to form linearity peak value rectifier circuit. Through R2/R2 partial pressure isolation, it is sent to double multi-channel BCD output A/D converter CA3162E, it also can....
An audio mixer is a handy circuit that will combine two or more audio signal sources into one signal channel. The figure shows an audio mixer that is built around the LM3900 CDA. The crux of this circuit is the three input networks, principally R3, R4, and....
The aim of a DC power supply is to provide the required level of DC power to the load using an AC supply at the input. Different applications require different attributes, but more often than not these days DC power supplies provide an accurate output....
