Mutchus

This circuit is a pulse oximeter , it is a medical device to indirectly measure the amount of oxygen in the blood of a person . The circuit is very simple and inexpensive to build , the sensor to be monitored only need an oscilloscope , but the case does not have an oscilloscope , here an article on how to make your pc a Oscilloscope . The operation is simple , light from an LED shines through on one side of your finger and is measured across the photo-transistor , a clothespin wood will engage the LED and the photo-transistor as a way to mount and align the sensor with finger . The monitor circuit uses only a single IC LM324 operational amplifier . There are three basic steps , the input signal is decoupled before being pre- amplified then passes through an adjustable low-pass filter to help eliminate noise 60Hz AC and finally a further low-pass filter in parallel with amplifier. Pulse Oximeter Circuit Diagra...

Here is a Simple Electronic Circuit Project of Simple Pushbutton Switch This circuit acts like a two-position switch but is operated using a pushbutton. After power has been applied, the circuit is in the following initial state: the bases of T1 and T2 are at the positive supply potential and the base of T3 is at ground potential. All transistors are cut off. The other contact of the pushbutton is at ground potential. No current flows through the relay coil and the status LED is off. Pushbutton Switch Circuit Diagram:   If the pushbutton is pressed, T2 and (after a slight delay due the RC network) T3 switch on. The collector of T3 is now nearly at ground potential, so current flows through the relay coil and the function LED is illuminated. T1 can also switch on. This situation is stable, since ground potential can reach the base of T2 via R1, so nothing changes when the pushbutton is released. C1 is charged via R3 to cause a positive potential to be present at the pushbutton. I...

Sometimes the need arises to construct a really simple oscillator. This could hardly be simpler than the circuit shown here, which uses just three components, and offers five separate octaves, beginning around Middle C (Stage 14). Octave # 5 is missing, due to the famous (or infamous) missing Stage 11 of the 4060B IC. We might call this a Colpitts ‘L’ oscillator, without the ‘C’. Due to the reactance of the 100-µH inductor and the propagation delay of the internal oscillator, oscillation is set up around 5 MHz. When this is divided down, Stage 14 approaches the frequency of Middle C (Middle C = 261.626 Hz). Stages 13, 12, 10, and 9 provide higher octaves, with Stages 8 to 4 being in the region of ultrasound. If the oscillator’s output is taken to the aerial of a Medium Wave Radio, L1 may serve as the search coil of a Pipe Locator, with a range of about 50 mm. This is tuned by finding a suitable heterodyne (beat note) on the medium wave band. In that case, piezo sounder Bz1 is omitted. ...

This is a Simple Period-To-Voltage Converter Circuit Diagram . The circuit input signal drives ICD. Because ICD`s positive input (V+) is slightly offset to + 0.1 V, its steady state output will be around +13 V. This voltage is sent to ICC through D2, setting ICC`s output to +13 V. Therefore, point D is cut off by Dl, and CI is charged by the current source.  Assuming the initial voltage on CI is zero, the maximum voltage (^Cinax) is given by: When the input goes from low to high, a narrow positive pulse is generated at point A. This pulse becomes -13 V at point B, which cuts off D2. ICC`s V+ voltage becomes zero. The charge on CI will be absorbed by ICC on in a short time.  The time constant of C2 and R5 determines the discharge period— about 10 /is. ICB is a buffer whose gain is equal to (R& + R9)~Rg = lM5. ICD`s average voltage will be (1362f 1.545) + 2 = 1052/. RIO and C3 smooth the sawtooth waveform to a dc output. Simple Period-To-Voltage Converter Circuit Diagram

This is a Simple 10 Amp Solar Charge Controller Circuit Diagram . The SCC2 is a solar charge controller, its function is to regulate the power flowing from a photovoltaic panel into a rechargeable battery. It features easy setup with one potentiometer for the float voltage adjustment, an equalize function for periodic overcharging, and automatic temperature compensation for better charging over a range of temperatures. 10 Amp Solar Charge Controller Circuit Diagram The goal of the circuit design was to make a charge controller with analog simplicity, high efficiency, and reliability. A medium power solar system can be built with a 12V solar panel up to 10 amps, the SCC2, and a rechargeable battery. The SCC2 works with lead acid, NiCD and NiMH batteries with ratings from less than one to several hundred amp-hours. With the appropriate parts selection, the SCC2 can be operated at 6V, 12V, 24V or other voltages. Specifications: Maximum solar panel current: 10 Amps Night time battery drain...

While LCR meters are readily available at reasonable cost, they do not measure the Q of an inductor. This circuit enables you to measure the Q of inductors with the aid of an RF signal generator. A capacitor is connected in parallel with the inductor to form a tuned circuit. By varying the frequency, you can measure the resonance frequency of the tuned circuit and its -3dB bandwidth. The Q is then the resonance frequency divided by the -3dB bandwidth. Transistor Q1 is an emitter follower acting as input buffer to drive RF transformer T1. The secondary winding of T1 then drives the parallel tuned circuit formed by the inductor under test (Lx), T1’s secondary and tuning capacitor VC. The tuned circuit so formed is buffered by JFET Q2 and transistor Q3 which form a cascode stage with about 3dB of gain. The JFET provides a high impedance so that the loading of the tuned circuit is minimal (note: an MPF102 can be substituted if you cannot obtain a 2N5485). The RF output from Q2's collec...

This circuit is used to save electricity in our homes to avoid spending too much . How it works ? This circuit of works to filter the AC voltage , and reduce the magnitude of the cosine curve AC current that will be read on the instrument KWH meters. KWH meters will work if there is a load wire passing through a coil of wire sensors to measure the AC current is passed, if the current through a lot of electricity. C1 and C2 worked as a deduction from stamping voltage if the switch is connected, so that equipment or components which enter the voltage was not much shocking. Part List : C1,C2 = 100pF / 400V or higher C3      = 10uF / 400V non polar capacitor Fuse   = 0.5W S1      = Switch on/off Use best quality capacitors Use the circuit on each item that requires AC power house to besaved using voltage field of electronics goods. Or if you take the trouble to make on each item , then use immediately near the KWH meter, to disconnect to tke...

This is a high quality power supply with a continuously variable stabilised output adjustable at any value between 0 and 30VDC. The circuit also incorporates an electronic output current limiter that effectively controls the output current from a few milliamperes (2 mA) to the maximum output of three amperes that the circuit can deliver. This feature makes this power supply indispensable in the experimenters laboratory as it is possible to limit the current to the typical maximum that a circuit under test may require, and power it up then, without any fear that it may be damaged if something goes wrong. There is also a visual indication that the current limiter is in operation so that you can see at a glance that your circuit is exceeding or not its preset limits.    Technical Specifications - Characteristics Input Voltage: ................ 24 VAC Input Current: ................ 3 A (max) Output Voltage: ............. 0-30 V adjustable Output Current: ............. 2 mA...

The circuit detects a sudden shadow falling on the light-sensor and sounds the bleeper when this happens. The circuit will not respond to gradual changes in brightness to avoid false alarms. The bleeper sounds for only a short time to prevent the battery running flat. Normal lighting can be used, but the circuit will work best if a beam of light is arranged to fall on the light-sensor. Breaking this beam will then cause the bleeper to sound. The light sensor is an LDR (light-dependant resistor), this has a low resistance in bright light and a high resistance in dim light. Simple Light Sensitive Alarm Circuit Diagram The light-sensitivity of the circuit can be adjusted by varying the 100k preset. The length of bleep can be varied from 0.5 to 10 seconds using the 1M preset. Using the 7555 low-power timer ensures that the circuit draws very little current (about 0.5mA) except for the short times when the bleeper is sounding (this uses about 7mA). If the circuit is switched on contin...

Circuit diagram: Description There are not many AM transmitters that are easier to build than this one because the inductor is not tapped and has a single winding. There is no need to wind the inductor as it is a readily available RF choke (eg, Jaycar Cat LF-1536). To make the circuit as small as possible, the conventional tuning capacitor has been dispensed with and fixed 220pF capacitors used instead. To tune it to a particular frequency, reduce one or both of the 220pF capacitors to raise the frequency or add capacitance in parallel to lower the frequency. Q1 is biased with a 1MO resistor to give a high input impedance and this allows the use of a crystal ear piece as a low cost microphone. author : Peter Goodwin Source http://www.extremecircuits.net/2010/05/simple-am-transmitter.html

DC 12V to 24V 2A Circuit diagram energy converter 12V to 24V 2A , which uses the integrated circuit CD4093 and CD40106 , and MOSFETs BUZ11 output . This converter can be used with some modifications as the source for Notebook charger , connecting equipment with voltage 24volts , etc. . For full operation of DC / DC converter input 12Volts must be a current of 4 amperes or more .    DC Converter  DC 12V to 24V 2A Circuit diagram

This is a 200W ATX PC Power Supply Circuit Diagram . Here I bring you wiring diagram of PCs power supply of DTK company. This power supply has ATX design and 200W performance. I was drawed diagram, when I repaired this power supply.   200W ATX PC Power Supply Circuit Diagram Circuit description This power supply circuit uses chip TL494. Similar circuit is used in the most power supplies with output power about 200W. Device use push-pull transistor circuit with regulation of output voltage. Input part a standby supply Line voltage goes through input filter circuit (C1, R1, T1, C4, T5) to the bridge rectifier. When voltage is switched from 230V to 115V, then rectifier works like a doubler. Varistors Z1 and Z2 have overvoltage protect function on the line input. Thermistor NTCR1 limits input current until capacitors C5 and C6 are charged. R2 and R3 are only for discharge capacitors after disconnecting power supply. When power supply is connected to the line voltage, then at first...

The LM3410 IC is a constant current LED driver useful in either boost con-verter or SEPIC design applications. A SEPIC (Single Ended Primary Induct-ance Conver ter) design allows the power supply’s output voltage to be set above, below or equal to its input voltage. In this application the chip is configured as a boost-converter (i.e. the output voltage is greater than the input voltage).  LM3410 LED Driver Circuit Diagram . The LM3410 is available in two fixed-frequency variants. Using either the 525 kHz or 1.6 MHz clock version it is possi-ble to build a ver y compact LED driver. The output stage can supply up to 2.8 A, allowing several high-power LED s to be driven from a rechargeable Lithium cell or several 1.5 V bat-teries. The chip also features a dimmer input giving simple PWM brightness control.Output current is defined by an external shunt resistor. To keep losses low the LM3410 uses an internal voltage reference of just 190 mV. Power dissipation in the shunt resistor...

This circuit is a simple two transistor (2N2222) FM transmitter. No license is required for this transmitter according to FCC regulations regarding wireless microphones. If powered by a 9 volt battery and used with an antenna no longer than 12 inches, the transmitter will be within the FCC limits. The microphone is amplified by Q1. Q2, C5, and L1 form an oscillator that operates in the 80 to 130 MHz range. The oscillator is voltage controlled, so it is modulated by the audio signal that is applied to the base of Q2. R6 limits the input to the RF section, and it's value can be adjusted as necessary to limit the volume of the input. L1 and C6 can be made with wire and a pencil. The inductor (L1) is made by winding two pieces of 24 gauge insulated wire, laid side by side, around a pencil six times. Remove the coil you have formed and unscrew the two coils apart from each other.    FM Transmitter Circuit Diagram One of these coils (the better looking of the two) will be used in th...

This is a Simple Detector Wireless Electricity Circuit Diagram . This is more of those circuits quite simple, but very useful, especially in the electrical area. This detector is an electric probe, which can also be used to detect the presence of high voltage on the wires and also as a touch switch, then the LED may be replaced with a relay to connect and disconnect a device (but only when something is detected).  The circuit is very simple and consists of only three transistors, 3 resistors, 1 LED and a 9V battery. He has a high gain by being in Darlington transistors, and the probe (copper strip) is a small piece of copper or a wire.  Detector Wireless Electricity Circuit Diagram

While detecting discontinuities on a circuit board, it is probable to include resistors, semiconductors or other elements in measurements. This situation may cause wrong results. On the other hand sometimes the voltage or current of the multimeter may defect some circuit components. Our circuit overcomes this inconvenient conditions. The circuit determines greater than 1 ohm values as discontinuity. Measure voltage is not more than 2mV. So no kind of diode, IC or other component is bypassed. Maximum current output of the circuit is about 200uA. Simple Wire Continuity Tester by LM709   Indicator of the circuit is a LED. Voltage supply may be two 9 Volt batteries. Voltage adjustment of the amplifier is done by P1 potentiometer. To do this process, first short circuit the probes and then turn P1 until LED brights. When you separate the probes again LED will fade out. This is a cheap and very useful circuit. You can build it on a PCB to use more easily.

Simple Advance Burglar alarm from dual-op amp Circuit . Device such as burglar alarms and sirens, whose basic purpose is to monitor certain conditions, make enjoyable projects because of the verity of sounds they can generate. Figure 1 shows a simple siren/alarm circuit using a dual-amp MC1458, audio amplifier LM380, and a 1-W speaker. The dual op-amp is used as a signal generator that produces square, pulse and triangular or sawtooth wave froms. The operation of the circuit is as follows. The A1 and A2 op-amps make up a waveform generator in which the output of A1 is a square wave or pulse waveform and that of A2 is either a triangular or sawtooth waveform.  The potentiometer R2 controls the frequency as well as the type of output waveform of op-amps A1 and A2. The switch SW1 connect the output of A1 or A2 to the audio power amplifier LM380, this in turn drives the speaker. Although not used in the circuit of figure 1, a potentiometer may be connected between (+) and (-) inputs o...

     This is the Simple Fluorescent Lamp Inverter Circuit Diagram. This inverter is very easy to construct, reliable, and even powerful enough to light up a 15W florescent tube (if you cool your transistor well). The only hard-to-find piece of this baby is the so-called yellow inverter transformer. It's a miniature high frequency transformer that has a 25mm x 20mm x 5mm ferrite core, 30 turns of primary, 15 turns of feedback, and 250 turns of secondary all concentric, wound on plastic frame than wrapped with a 'yellow' adhesive tape. If you can't find it in your local electronic shops then search for old portable rechargeble florescent lanterns since they have at least one yellow inverter. Of course you can wind a handmade transformer which would do the same but it is a very difficult task when you don't have an original to inspire and it will still need an appropriate ferrite core. Simple Fluorescent Lamp Inverter Circuit Diagram       This ...

This is a simple Simple LM317 Circuit Diagram. The LM317 is AN adjustable three terminal transformer that is capable of supply 1.2 to 37 volts with a secure 1.5A output current. The LM317 is prepackaged terribly} normal electronic transistor package that makes it very simple to mount in your circuits.  Simple LM317 Circuit Diagram Overview The LM317 series of adjustable 3-terminal positive voltage regulators is capable of supply in more than 1.5A over a 1.2V to 37V output vary. they're exceptionally simple to use and need solely 2 external resistors to line the output voltage. Further, each line and cargo regulation square measure higher than normal mounted regulators. In addition to higher performance than mounted regulators, the LM317 series offers full overload protection out there solely in IC's. enclosed on the chip square measure current limit, thermal overload protection and safe space protection. The LM317 makes AN particularly easy adjustable change regulator, a ...

This is a Simple Complementary metal–oxide–semiconductor connect switch circuit diagram , CMOS technology is used in microprocessors, microcontrollers, static RAM, and other digital logic circuits. This connect switch does not rely on mains hum for switching-It-can be used with battery powered circuits.  Simple Cmos Connect Switch Circuit Diagram Schmitt trigger IC1 forms a 100 kHz oscillator and IC2a which is biased into the linear region, amplifies the output and charges CI via the diode. IC2b acts as a level detector. When the sensor is touched, the oscillator signal is severely attenuated which causes CI to discharge and IC2b to change state.Sourced by : Circuitsstream