New Circuits Page 65
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Even as display devices move toward digital video, they retain the legacy of an RF-modulated analog TV output. That output is specified in the US by the National Television Standards Committee (NTSC), and utilized in security applications and in the Digital....
-
The Intersil ICL32XX devices are 3. 0V to 5. 5V powered RS-232 transmitters/receivers which meet ElA/TIA-232 and V. 28/V. 24 specifications, even at VCC = 3. 0V. Targeted applications are PDAs, Palmtops, and notebook and laptop computers where the low....
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This is a small tv transmitter circuit wich trasmittes in VHF, negative sound modulation and PAL video modulation. It is suitable in countries where the B and G system is used. T1 which type of transformer. what is C1 value. what means of letter P which in....
-
Using the ISL8012 high efficiency, monolithic, synchronous step-down DC DC converter can be designed a very simple DC DC converter electronic project that can support a maximum output current up to 2A (continuous output current ) from a 2. 7V to 5. 5V input....
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An RF condenser design, it was powered by 12v, supplied to the microphone via the mike cable using a phantom circuit. This is the first known usage of a phantom circuit for microphone powering[1]. Sometime around 1970, Neumann introduced the Fet-80 series of....
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-
Use this fm antenna amplifier in areas where the signal reception of FM stations is too bad. This circuit is just the right thing to do it. It is designed...
-
-
This is a well designed basic FM transmitter that you can easily recive the signals transmitted from this transmitter in a 1-2km range with using a normal FM reciever. Another property of this circuit is that the bobin is placed on the printed circuit board.....
-
The TDA7010T is a monolithic integrated circuit for mono FM portable radios, where a minimum on peripheral components is important (small dimensions and low costs). The IC has an FLL (Frequency-Locked....
-
This simple 220V power interface is intended as an interface for monitoring electric equipments and devices using a computer. The interface only senses whether the device being monitored is turned on or off. The most important aspect of the circuit is the....
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The frequency is controlled by the pin 5 of the IC. When the supply is switched ON, the capacitor charges slowly and this alters the voltage at pin 5 of the IC hence the frequenct gradually increases. After the capacitor is fully charged, the frequency no....
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This is a simple circuit for automatic switchover between battery and USB port. This circuit uses more general step-up converter architecture. Compared with an....
-
A difficult problem in the design of conventional stereo tone controls is obtaining synchronous travel of the potentiometers. Even a slight error in synchrony can cause phase and amplitude differences between the two channels. Moreover, linear potentiometers....
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This variation on my Digital Setting Circles project was created by Craig Combes. He provided the following content so others could recreate his version. Thanks, Craig! Many people use Dave`s serial DSC board with a serial to Bluetooth adapter and that can....
-
The open-loop concept of oscillator design is often met with considerable skepticism by engineers familiar with classic oscillator terminology. For comfort consider Figure 2-4A where the oscillator cascade is drawn with only the RF components. Next, the....
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Control a little 5v motor from an external power supply by using the Arduino to trigger a transistor. Like this: Is that at all correct Will it work I want to experiment but I don`t want to break my new toy in the process. The transistor I am using is an....
-
Until Willow Garage was acquired, I was working there as a Web Robotics Engineer. Really, it`s just a title I gave myself for a full-stack engineer who deals with the issues of real-time, distributed robot control. I`m on GitHub, of course. My most popular....
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Place the transmitter about 10 feet from a FM radio. Set the radio to somewhere about 89 - 90 MHz. Walk back tothe FM transmitter and turn it on. Spread the winding of the coil apart by approximately 1mm from each other. No coilwinding should be touching....
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A simple yet accurate automatic, regulated 6/12/24 volt lead acid battery charger circuit is explained in this article. The circuit switches off the current to the battery as soon as the battery reaches full charge. An illuminated LED at the output....
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-
this LM4702 has found a new home in a Crown DC150 -- for some reason the driver board in the crown was fried but the power supply in good shape:....
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This is a fairly simple schematic of the amplifier and filter. At the core of the circuit is an LM124 op-amp running in an inverting configuration. Th....
-
-
This circuit uses the popular and easy to find LM3914 IC. This IC is very simple to drive, needs no voltage regulators (it has a built in voltage regulator) and can be powered from almost every source. When the test button is pressed, the Car battery voltage....
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This circuit also prevents the shutdown circuit of the IR2161 from operating in the normal way and therefore the external SCR based protection circuit also needs to be added. ..
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This project started from seeing pages describing arcstarters that could be constructed for practically no cost from stuff just laying around in the typical tinker`s shop. It has been a fun project, but I have a basement crammed full of stuff and I still had....
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The following circuit shows about Chevrolet Malibu 1997 Electrical Wiring Diagram. Features: 2.4L (VIN T) Engine Performance Circuits,. Component: ....
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My projects typically involve many LEDs and microcontrollers. However sometimes I just love the simplest of things with LEDs. One of the very basic L....
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A lot of FM transmitter circuits have been already published here. This just another one, a simple two transistor FM transmitter. The first stage of the circuit is a preamplifier stage based on transistor Q1. This is a collector to base biased amplifier....
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Below is two single ended circuits which connected back to back give differential input. This circuit is not only has differential input feature, but also high impedance, much higher compared with the analog ammeter without this circuit. Here is the....
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IR2156 can offer solution of high cost-effectiveness for fluorescent electron ballast. It can integrate lighting tube error protection and the programmable working frequency with warm-up, lighting and ballast continue working...
-
Laser-receiver circuits must bias their avalanche photo diodes (APD) to achieve optimal gain. Unfortunately, an APD""s gain depends on the operating temperature. The circuit controls the operating voltage of an APD over a large temperature range to maintain....
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This is a design circuit for mass air flow sensor circuit. The mass air flow sensors converts the amount of air drawn into the engine into a voltage signal. The primary components of the MAF sensor are thermistor, a platinum hot wire, and an electronic....
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The 555 astable board uses a 555 timer in its astable configuration. This means that it outputs a square wave or a series of high and low signals. The speed that the signal goes high and low is set by the capacitor C1 and variable resistor R3. The board is....
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Not only on ecologically grounds but also economically it makes sense to collect rainwater for use in the garden and increasingly for `grey water` domestic use. People who take rainwater collection seriously use large underground tanks for storage. The....
-
For several years now, a rear fog lamp has been mandatory for trailers and caravans in order to improve visibility under foggy conditions. When this fog lamp is switched on, the fog lamp of the pulling vehicle must be switched of to avoid irritating....
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This 555 timer circuit Remote control Jammer device it s useful when we need to block someone to use the remote control (children that change frequently t....
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The panels look good and the cases are neat. What are the cases made from. MDF board I noticed the panels are recessed quite a bit too. I`m guessing this is to protect the knobs etc. I`m curious how deep your cases are I`m working on getting my circuits....
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This circuit is a circuit diagram to convert the speaker into the microphone. In principle When sound waves fall on the diaphragm of a speaker, there will be fluctuations in the coil and the induced voltage will be no small proportion. This induced voltage....
-
It is one of the most popular type of oscillators used in audio and sub-audio frequency ranges (20 20 kHz). This type of oscillator is simple in design, compact in size, and remarkably stable in its frequency output. Furthermore, its output is relatively....
-
FM and AM transmitter in one small device built of cd4001 integrated circuit. It broadcasts on 20MHz(AM) and 100Mhz(FM)....
-
Hi I am currently working through the prototype of my first guitar pedal. I am having issues with the input buffer, and I would like someone to look....
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Real time controller is a device used to exercise control over household device continuously ongoing and scheduled. The series of Real Time Controllers with microcontroller AT89C2051 which dituls in this article is a tool that can do that serve targeted. The....
-
When the water-level is below the steel rods, no contact is occurring from the metal can and the rods, which are supported by a small insulated (wooden) board. The small circuit built around IC1 draws no current and therefore no voltage drop is generated....
-
This circuit generates a two-tone effect very much alike the cuckoo sound. It can be used for door-bells or other purposes thanks to a built-in audio amplifier and loudspeaker....
-
-
This handy circuit can be used to charge from one to 12 NiCd cells from a car battery. Up to six cells can be charged with switch S1 in the normal posit....
-
The main amplifying stages are triode connected 6088 stages. As indicated from the previous part, there are two amplifying stages. This provides a non-inverted input to output connection, as well as sufficient gain to incorporate tone control. The tone....
-
1N4001 a 1Amp Silicon rectifier with voltage range of 50 to 1000 Volts and possessing features such as guaranteed high temperature soldering, high current capability, diffused junction, low reverse leakage, utilizes void-free molded plastic technique for low....
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This is a 7 tube 20 watt amplifier that must be used in conjunction with a pre amplifier having volume an tone controls. For this, I recommend this 6 tube pre-amp. With this amplifier you may use 6BQ5 output tubes. A 5U4-G rectifier is used so that the power....
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This oscillator is a variation of the oscillator presented by Ulrich L. Rohde, DJ2LR, in his article "Evaluating Noise Sideband Performance in Oscillators", Ham Radio, October 1978, Page 51. The original circuit is at the bottom of the web page "4 MHz....
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This circuit shows an active antenna that can be used for AM, FM, and shortwave (SW). On the shortwave band this active antenna is comparable to a 20 to 30 foot wire antenna. This circuit is designed to be used on receivers that use untuned wire antennas,....
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This basic PIC-based RS-232 serial interface can control up to 120 digital TTL outputs....
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Multiplexed 7-Segment Display PCB The display PCB consists of four MAN72 7-segment common-anode ....
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A MIDI interface for an automatic accompaniment or controlling an MIDI expander. MIDIvice supports both manuals and has some nifty program features. It`s a MIDI output interface for upper and lower manual, working with a dirt-cheap 8031 and single-sided PCBs....
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-
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The two circuits illustrate using the 555 timer to close a relay for a predetermined amount of time by pressing a momentary N/O push button. The circuit on the left can be used for long time periods where the push button can be pressed and released before....
-
Here is a simple circuit for a one transistor Audion type radio powered by a 1. 5 V battery. It employs a set of standard low-impedance headphones with the headphone socket wired so that the two sides are connected in series thus giving an impedance of 64 ©.....
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This post shares a proximity detector circuit comprising mainly NE555 IC. This circuit can be used for burglar alarms based on beam interruption, with the added advantage that the transmitter and receiver are housed in the same enclosure, avoiding any wiring....
-
Circuit designed for 5-mA meter movement uses two-stage voltage ampilfer Q1-Q2 with emitter-follower output Q3 serving as impedance-matching stage AF input for S-9 reading is 25-30mV P-P and forfull scale is 50-60mV P-P Frequency response is 500 Hz to 10....
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The LA1061M is an Antenna switching controller for mobile Radio equipment. The LA1061M uses a number of inputs from the receiver circuitry to select the main Antenna or sub-antenna according to signal strength and quality. Weak and strong signals are....
-
This simple circuit has helped me out on many occasions. It is able to check transistors, in the circuit, down to 40 ohms across the collector-base or base-emitter junctions. It can also check the output power transistors on amplifier circuits. Circuit....
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This is Hot Water Level Indicator circuit. This circuit can be used to monitor level of hot water in a tank. This circuit is simple and inexpensive. this....
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-
Good pitching beats good hitting and a good magnetic mic beats a good carbon mic. This one transistor carbon mic converter takes a carbon mic input and converts it to the magnetic variety. Note that no ground connection is used, even if the circuit is built....
-
The Intersil ISL43485 is a high speed BiCMOS 3. 3V powered, single transceiver that meets both the RS-485 and RS-422 standards for balanced communication. Unlike some competitive devices, this Intersil transceiver is specified for 10% tolerance supplies (3V....
-
LM331 is the single voltage / frequency conversion IC within 1.9 v reference voltage, current switch, comparator and flip-flop, etc. In order to expand the range, the circuit is added A1 op amp. The reference current IR is decided by (Rl + R (RPl)), as the....
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This is the circuit diagram of a simple electronic combination lock using IC LS 7220. This circuit can be used to activate a relay for controlling (on & off) any device when a preset combination of 4 digits are pressed. The circuit can be operated from 5V to....
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Addition of dual-triode amplifier V2 to conventional peak voltmeter reduces charging time constant while increasing available time for measuring peak value. Linearity is good up to 40 v. -M. Uno, Amplifier Improves Peak Voltmeter Response, Electronics,....
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The DIAC is a 28V bidirectional (bilateral) trigger device that is used on virtually all inexpensive phase controls. The trigger voltage is somewhat high for phase control of 115VAC. Years ago, there was a similar low voltage (6 to 8V) trigger device called....
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Fly back transformers are commonly found in television sets and can put out 50, 000 volts, enough power to lift a 350 pound man up and throw him back 10-20 feet killing him instantly. Also the component`s are picky sometimes and reversing the polarity....
-
-
This is the schematic for an FM transmitter with 3 to 3.5 W output power that can be used between 90 and 110 MHz. Although the stability isn`t so bad, a PLL can be used on this circuit....
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This article describes the Flip-Flop Flashers, Buzzers CIRCUIT (2N4401). The content is very simple, very helpful. Components in this article can help you understand better understanding of this article. For example, in this article, you can go to find and....
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As the figure 14-41 shows, the multivibrator is composed of the 555 and some capacitance resistance components, the oscillation frequency depends on the values of Ra, R16 and C3. f=1.44/(Ra+2R16)C3, the Ra of the formula corresponds to the different values....
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Most of the frequency multiplier circuit using IC phase locked loop (PLL).It will increase the frequency to an integer only. But this circuit can double the....
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Here the Arduino UNO schematic diagram (click to enlarge): About Arduino UNO: The Arduino Uno is really a microcontroller board based on the ATmega328. It has 14 digital input/output pins (of which 6 may be employed as PWM outputs), 6 analog inputs, a 16 MHz....
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A diagram of an active loudspeaker. The LF353 of, National Semiconductor, is going to split audio signal into three bands. SANYO LA47536 is going to amplify these signals. In stereo mode, we shall have the action of eight high speakers who are going to....
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Make sure to double-check your connections using the circuit diagram and schematic below. You can use this while you follow along in the tutorial vide....
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One Advantage of these two units is the Sensor can be placed Away from the heater, therefore sensing the Actual Room temperature, not the direct heat from the heater. These can also be used in a confined space with a Heat Lamp, to create a Drying Oven. This....
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This is a circuit diagram for a solid state charge detector. It can detect very weak electric fields. The circuit has three components: a 6-volt battery, a light-emitting diode (LED), and a field-effect IC ADM666A..
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This circuit based project demonstrates the working of 555 timer in astable mode to generate pulses of time period 0. 5 second. This pulse can be further used for anything where we need a pulse such as to blink a LED or to create fashionable blinking lights.....
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You checked the transistor by measuring the resistance between the different pins. Sometimes it has problems, such as when measuring the resistance between the...
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Today may of our appliances come with displays and buttons. Instead of motors and gears, many household items today have embedded Microcontrollers. We are going to explore how we can experiment with Microcontrollers at home....
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The voltage rating on the 470 µF capacitor is not critical, so long as it generously exceeds the maximum power supply voltage. In this particular circuit, that maximum voltage is 12 volts. Be sure you connect this capacitor in the circuit properly,....
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The full schematic for this project is really, really big so if you want to see it, go ahead and click the picture below. Since the schematic is so big I split the explanation of how things are connected together into three sections. The Hsync Generator,....
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A reasonably effective bfo (bifilar oscillator). Its performance is not comparable to more advanced commercial products, of course, but it still works. Anyway, during WWII metal detectors based on the same principle were utilized my combat engineers of many....
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In previous article about how to make a radio we have discussed a simple crystal radio receiver circuit. The schematic mentioned here is also a simple AM radio circuit but it is not using a crystal, it is using high gain preamplifier stage of transistor BC....
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The full wave phase control circuit below was found in a RCA power circuits book from 1969. The load is placed in series with the AC line and the four diodes provide a full wave rectified voltage to the anode of a SCR. Two small signal transistors are....
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The following circuit shows about BUZ902DP 300 Watt Audio Power Amplifier Circuit Diagram. Features: 20 Hz 20 kHz Audio Frequency Linearity, ....
Even as display devices move toward digital video, they retain the legacy of an RF-modulated analog TV output. That output is specified in the US by the National Television Standards Committee (NTSC), and utilized in security applications and in the Digital....
The Intersil ICL32XX devices are 3. 0V to 5. 5V powered RS-232 transmitters/receivers which meet ElA/TIA-232 and V. 28/V. 24 specifications, even at VCC = 3. 0V. Targeted applications are PDAs, Palmtops, and notebook and laptop computers where the low....
This is a small tv transmitter circuit wich trasmittes in VHF, negative sound modulation and PAL video modulation. It is suitable in countries where the B and G system is used. T1 which type of transformer. what is C1 value. what means of letter P which in....
Using the ISL8012 high efficiency, monolithic, synchronous step-down DC DC converter can be designed a very simple DC DC converter electronic project that can support a maximum output current up to 2A (continuous output current ) from a 2. 7V to 5. 5V input....
An RF condenser design, it was powered by 12v, supplied to the microphone via the mike cable using a phantom circuit. This is the first known usage of a phantom circuit for microphone powering[1]. Sometime around 1970, Neumann introduced the Fet-80 series of....
Use this fm antenna amplifier in areas where the signal reception of FM stations is too bad. This circuit is just the right thing to do it. It is designed...
This is a well designed basic FM transmitter that you can easily recive the signals transmitted from this transmitter in a 1-2km range with using a normal FM reciever. Another property of this circuit is that the bobin is placed on the printed circuit board.....
The TDA7010T is a monolithic integrated circuit for mono FM portable radios, where a minimum on peripheral components is important (small dimensions and low costs). The IC has an FLL (Frequency-Locked....
This simple 220V power interface is intended as an interface for monitoring electric equipments and devices using a computer. The interface only senses whether the device being monitored is turned on or off. The most important aspect of the circuit is the....
The frequency is controlled by the pin 5 of the IC. When the supply is switched ON, the capacitor charges slowly and this alters the voltage at pin 5 of the IC hence the frequenct gradually increases. After the capacitor is fully charged, the frequency no....
This is a simple circuit for automatic switchover between battery and USB port. This circuit uses more general step-up converter architecture. Compared with an....
A difficult problem in the design of conventional stereo tone controls is obtaining synchronous travel of the potentiometers. Even a slight error in synchrony can cause phase and amplitude differences between the two channels. Moreover, linear potentiometers....
This variation on my Digital Setting Circles project was created by Craig Combes. He provided the following content so others could recreate his version. Thanks, Craig! Many people use Dave`s serial DSC board with a serial to Bluetooth adapter and that can....
The open-loop concept of oscillator design is often met with considerable skepticism by engineers familiar with classic oscillator terminology. For comfort consider Figure 2-4A where the oscillator cascade is drawn with only the RF components. Next, the....
Control a little 5v motor from an external power supply by using the Arduino to trigger a transistor. Like this: Is that at all correct Will it work I want to experiment but I don`t want to break my new toy in the process. The transistor I am using is an....
Until Willow Garage was acquired, I was working there as a Web Robotics Engineer. Really, it`s just a title I gave myself for a full-stack engineer who deals with the issues of real-time, distributed robot control. I`m on GitHub, of course. My most popular....
Place the transmitter about 10 feet from a FM radio. Set the radio to somewhere about 89 - 90 MHz. Walk back tothe FM transmitter and turn it on. Spread the winding of the coil apart by approximately 1mm from each other. No coilwinding should be touching....
A simple yet accurate automatic, regulated 6/12/24 volt lead acid battery charger circuit is explained in this article. The circuit switches off the current to the battery as soon as the battery reaches full charge. An illuminated LED at the output....
this LM4702 has found a new home in a Crown DC150 -- for some reason the driver board in the crown was fried but the power supply in good shape:....
This is a fairly simple schematic of the amplifier and filter. At the core of the circuit is an LM124 op-amp running in an inverting configuration. Th....
This circuit uses the popular and easy to find LM3914 IC. This IC is very simple to drive, needs no voltage regulators (it has a built in voltage regulator) and can be powered from almost every source. When the test button is pressed, the Car battery voltage....
This circuit also prevents the shutdown circuit of the IR2161 from operating in the normal way and therefore the external SCR based protection circuit also needs to be added. ..
This project started from seeing pages describing arcstarters that could be constructed for practically no cost from stuff just laying around in the typical tinker`s shop. It has been a fun project, but I have a basement crammed full of stuff and I still had....
The following circuit shows about Chevrolet Malibu 1997 Electrical Wiring Diagram. Features: 2.4L (VIN T) Engine Performance Circuits,. Component: ....
My projects typically involve many LEDs and microcontrollers. However sometimes I just love the simplest of things with LEDs. One of the very basic L....
A lot of FM transmitter circuits have been already published here. This just another one, a simple two transistor FM transmitter. The first stage of the circuit is a preamplifier stage based on transistor Q1. This is a collector to base biased amplifier....
Below is two single ended circuits which connected back to back give differential input. This circuit is not only has differential input feature, but also high impedance, much higher compared with the analog ammeter without this circuit. Here is the....
IR2156 can offer solution of high cost-effectiveness for fluorescent electron ballast. It can integrate lighting tube error protection and the programmable working frequency with warm-up, lighting and ballast continue working...
Laser-receiver circuits must bias their avalanche photo diodes (APD) to achieve optimal gain. Unfortunately, an APD""s gain depends on the operating temperature. The circuit controls the operating voltage of an APD over a large temperature range to maintain....
This is a design circuit for mass air flow sensor circuit. The mass air flow sensors converts the amount of air drawn into the engine into a voltage signal. The primary components of the MAF sensor are thermistor, a platinum hot wire, and an electronic....
The 555 astable board uses a 555 timer in its astable configuration. This means that it outputs a square wave or a series of high and low signals. The speed that the signal goes high and low is set by the capacitor C1 and variable resistor R3. The board is....
Not only on ecologically grounds but also economically it makes sense to collect rainwater for use in the garden and increasingly for `grey water` domestic use. People who take rainwater collection seriously use large underground tanks for storage. The....
For several years now, a rear fog lamp has been mandatory for trailers and caravans in order to improve visibility under foggy conditions. When this fog lamp is switched on, the fog lamp of the pulling vehicle must be switched of to avoid irritating....
This 555 timer circuit Remote control Jammer device it s useful when we need to block someone to use the remote control (children that change frequently t....
The panels look good and the cases are neat. What are the cases made from. MDF board I noticed the panels are recessed quite a bit too. I`m guessing this is to protect the knobs etc. I`m curious how deep your cases are I`m working on getting my circuits....
This circuit is a circuit diagram to convert the speaker into the microphone. In principle When sound waves fall on the diaphragm of a speaker, there will be fluctuations in the coil and the induced voltage will be no small proportion. This induced voltage....
It is one of the most popular type of oscillators used in audio and sub-audio frequency ranges (20 20 kHz). This type of oscillator is simple in design, compact in size, and remarkably stable in its frequency output. Furthermore, its output is relatively....
FM and AM transmitter in one small device built of cd4001 integrated circuit. It broadcasts on 20MHz(AM) and 100Mhz(FM)....
Hi I am currently working through the prototype of my first guitar pedal. I am having issues with the input buffer, and I would like someone to look....
Real time controller is a device used to exercise control over household device continuously ongoing and scheduled. The series of Real Time Controllers with microcontroller AT89C2051 which dituls in this article is a tool that can do that serve targeted. The....
When the water-level is below the steel rods, no contact is occurring from the metal can and the rods, which are supported by a small insulated (wooden) board. The small circuit built around IC1 draws no current and therefore no voltage drop is generated....
This circuit generates a two-tone effect very much alike the cuckoo sound. It can be used for door-bells or other purposes thanks to a built-in audio amplifier and loudspeaker....
This handy circuit can be used to charge from one to 12 NiCd cells from a car battery. Up to six cells can be charged with switch S1 in the normal posit....
The main amplifying stages are triode connected 6088 stages. As indicated from the previous part, there are two amplifying stages. This provides a non-inverted input to output connection, as well as sufficient gain to incorporate tone control. The tone....
1N4001 a 1Amp Silicon rectifier with voltage range of 50 to 1000 Volts and possessing features such as guaranteed high temperature soldering, high current capability, diffused junction, low reverse leakage, utilizes void-free molded plastic technique for low....
This is a 7 tube 20 watt amplifier that must be used in conjunction with a pre amplifier having volume an tone controls. For this, I recommend this 6 tube pre-amp. With this amplifier you may use 6BQ5 output tubes. A 5U4-G rectifier is used so that the power....
This oscillator is a variation of the oscillator presented by Ulrich L. Rohde, DJ2LR, in his article "Evaluating Noise Sideband Performance in Oscillators", Ham Radio, October 1978, Page 51. The original circuit is at the bottom of the web page "4 MHz....
This circuit shows an active antenna that can be used for AM, FM, and shortwave (SW). On the shortwave band this active antenna is comparable to a 20 to 30 foot wire antenna. This circuit is designed to be used on receivers that use untuned wire antennas,....
This basic PIC-based RS-232 serial interface can control up to 120 digital TTL outputs....
Multiplexed 7-Segment Display PCB The display PCB consists of four MAN72 7-segment common-anode ....
A MIDI interface for an automatic accompaniment or controlling an MIDI expander. MIDIvice supports both manuals and has some nifty program features. It`s a MIDI output interface for upper and lower manual, working with a dirt-cheap 8031 and single-sided PCBs....
The two circuits illustrate using the 555 timer to close a relay for a predetermined amount of time by pressing a momentary N/O push button. The circuit on the left can be used for long time periods where the push button can be pressed and released before....
Here is a simple circuit for a one transistor Audion type radio powered by a 1. 5 V battery. It employs a set of standard low-impedance headphones with the headphone socket wired so that the two sides are connected in series thus giving an impedance of 64 ©.....
This post shares a proximity detector circuit comprising mainly NE555 IC. This circuit can be used for burglar alarms based on beam interruption, with the added advantage that the transmitter and receiver are housed in the same enclosure, avoiding any wiring....
Circuit designed for 5-mA meter movement uses two-stage voltage ampilfer Q1-Q2 with emitter-follower output Q3 serving as impedance-matching stage AF input for S-9 reading is 25-30mV P-P and forfull scale is 50-60mV P-P Frequency response is 500 Hz to 10....
The LA1061M is an Antenna switching controller for mobile Radio equipment. The LA1061M uses a number of inputs from the receiver circuitry to select the main Antenna or sub-antenna according to signal strength and quality. Weak and strong signals are....
This simple circuit has helped me out on many occasions. It is able to check transistors, in the circuit, down to 40 ohms across the collector-base or base-emitter junctions. It can also check the output power transistors on amplifier circuits. Circuit....
This is Hot Water Level Indicator circuit. This circuit can be used to monitor level of hot water in a tank. This circuit is simple and inexpensive. this....
Good pitching beats good hitting and a good magnetic mic beats a good carbon mic. This one transistor carbon mic converter takes a carbon mic input and converts it to the magnetic variety. Note that no ground connection is used, even if the circuit is built....
The Intersil ISL43485 is a high speed BiCMOS 3. 3V powered, single transceiver that meets both the RS-485 and RS-422 standards for balanced communication. Unlike some competitive devices, this Intersil transceiver is specified for 10% tolerance supplies (3V....
LM331 is the single voltage / frequency conversion IC within 1.9 v reference voltage, current switch, comparator and flip-flop, etc. In order to expand the range, the circuit is added A1 op amp. The reference current IR is decided by (Rl + R (RPl)), as the....
This is the circuit diagram of a simple electronic combination lock using IC LS 7220. This circuit can be used to activate a relay for controlling (on & off) any device when a preset combination of 4 digits are pressed. The circuit can be operated from 5V to....
Addition of dual-triode amplifier V2 to conventional peak voltmeter reduces charging time constant while increasing available time for measuring peak value. Linearity is good up to 40 v. -M. Uno, Amplifier Improves Peak Voltmeter Response, Electronics,....
The DIAC is a 28V bidirectional (bilateral) trigger device that is used on virtually all inexpensive phase controls. The trigger voltage is somewhat high for phase control of 115VAC. Years ago, there was a similar low voltage (6 to 8V) trigger device called....
Fly back transformers are commonly found in television sets and can put out 50, 000 volts, enough power to lift a 350 pound man up and throw him back 10-20 feet killing him instantly. Also the component`s are picky sometimes and reversing the polarity....
This is the schematic for an FM transmitter with 3 to 3.5 W output power that can be used between 90 and 110 MHz. Although the stability isn`t so bad, a PLL can be used on this circuit....
This article describes the Flip-Flop Flashers, Buzzers CIRCUIT (2N4401). The content is very simple, very helpful. Components in this article can help you understand better understanding of this article. For example, in this article, you can go to find and....
As the figure 14-41 shows, the multivibrator is composed of the 555 and some capacitance resistance components, the oscillation frequency depends on the values of Ra, R16 and C3. f=1.44/(Ra+2R16)C3, the Ra of the formula corresponds to the different values....
Most of the frequency multiplier circuit using IC phase locked loop (PLL).It will increase the frequency to an integer only. But this circuit can double the....
Here the Arduino UNO schematic diagram (click to enlarge): About Arduino UNO: The Arduino Uno is really a microcontroller board based on the ATmega328. It has 14 digital input/output pins (of which 6 may be employed as PWM outputs), 6 analog inputs, a 16 MHz....
A diagram of an active loudspeaker. The LF353 of, National Semiconductor, is going to split audio signal into three bands. SANYO LA47536 is going to amplify these signals. In stereo mode, we shall have the action of eight high speakers who are going to....
Make sure to double-check your connections using the circuit diagram and schematic below. You can use this while you follow along in the tutorial vide....
One Advantage of these two units is the Sensor can be placed Away from the heater, therefore sensing the Actual Room temperature, not the direct heat from the heater. These can also be used in a confined space with a Heat Lamp, to create a Drying Oven. This....
This is a circuit diagram for a solid state charge detector. It can detect very weak electric fields. The circuit has three components: a 6-volt battery, a light-emitting diode (LED), and a field-effect IC ADM666A..
This circuit based project demonstrates the working of 555 timer in astable mode to generate pulses of time period 0. 5 second. This pulse can be further used for anything where we need a pulse such as to blink a LED or to create fashionable blinking lights.....
You checked the transistor by measuring the resistance between the different pins. Sometimes it has problems, such as when measuring the resistance between the...
Today may of our appliances come with displays and buttons. Instead of motors and gears, many household items today have embedded Microcontrollers. We are going to explore how we can experiment with Microcontrollers at home....
The voltage rating on the 470 µF capacitor is not critical, so long as it generously exceeds the maximum power supply voltage. In this particular circuit, that maximum voltage is 12 volts. Be sure you connect this capacitor in the circuit properly,....
The full schematic for this project is really, really big so if you want to see it, go ahead and click the picture below. Since the schematic is so big I split the explanation of how things are connected together into three sections. The Hsync Generator,....
A reasonably effective bfo (bifilar oscillator). Its performance is not comparable to more advanced commercial products, of course, but it still works. Anyway, during WWII metal detectors based on the same principle were utilized my combat engineers of many....
In previous article about how to make a radio we have discussed a simple crystal radio receiver circuit. The schematic mentioned here is also a simple AM radio circuit but it is not using a crystal, it is using high gain preamplifier stage of transistor BC....
The full wave phase control circuit below was found in a RCA power circuits book from 1969. The load is placed in series with the AC line and the four diodes provide a full wave rectified voltage to the anode of a SCR. Two small signal transistors are....
The following circuit shows about BUZ902DP 300 Watt Audio Power Amplifier Circuit Diagram. Features: 20 Hz 20 kHz Audio Frequency Linearity, ....
![LED Flasher Circuit II [PIC]](uploads/55/circuit-diagram-flasher.gif "LED Flasher Circuit II [PIC]")
