TREE

Build a Square A to Sine Wave Converter Circuit Diagram. This is a simple circuit diagram in this circuit using Two pairs of MOSFETs form a bridge that alternately switches current in opposite directions. Two parallel-resonant LC circuits complete the converter. The Ll/C1 combination is resonant at the fundamental frequency; the L2/C2 combination is resonant at the clock frequency`s third harmonic and acts as a trap.  Square A to Sine Wave Converter Circuit Diagram Tl and C3 ensure that both halves of the MOSFET bridge are never on at the same time by providing a common delay to the gate drive of each half. Select the values of R1 and C3 to yield a time constant that`s less than 5% of the clock`s period. You can add an output amplifier for additional buffering and conditioning of the circuit`s sine-wave output.

Small and portable unit, Useful for old men and old women This low-cost, general-purpose electronic hearing aid works off 3V DC (2x1.5V battery). The circuit can be easily assembled on a veroboard. For easy assembling and maintenance, use an 8-pin DIP IC socket for TDA2822M. Circuit Diagrams: A Low Cost hearing Aid Schematic Parts: P1 = 10K R1 = 2.2K R2 = 330K R3 = 680R R4 = 33R R5 = 100R R6 = 4.7R R7 = 4.7R R8 = 220R C1 = 0.01uF-10V C2 = 100nF-63V C3 = 47uF-10V C4 = 10uF-10V C5 = 0.01uF-10V C6 = 100uF-10V C7 = 100nF-63V C8 = 100nF-63V D1 = Red LED Q1 = BC547 IC1 = TDA2822M EP1 = Mono Earphone 32R SW1 = On-Off Switch Circuit Operation: In this circuit, transistor Q1 and associated components form the audio signal preamplifier for the acoustic signals picked up by the condenser microphone and converted into corresponding electrical signals. Resistor R5 and capacitor C3 decouple the power supply of the preamplifier stage. Resistor R1 biases the internal circuit of the low-voltage conden...

This is a simple power on switching circuit . This type of reset pulse is ideally provided by this circuit. Because of the high input impedance of the Schmidt trigger, long reset pulse times may be achieved without the excess dissipation that results when both output devices are on simultaneously, as in an ordinary gate device (B). A reset pulse is often required at power-on in a digital system. See circuit diagram below. Simple Power On Reset Circuit Diagram

I have built this amplifier and it does sound good. It requires a preamp as it hasn't got much gain. It requires big heat sinks and a large transformer and a great power supply and careful wiring, but in the end it is xtremely simple and it sounds very good. The zener diode rejects any ripple coming from the power supply, But you still only want a ripple of 10mV max. The ripple reaching the input is amplified, so the zener diode gets rid of that, but whatever ripple there is will still reach the power stage.

The supply receives - 20 V from the rectifier/filter which is fed to the collector of the Darlington pnp pass transistor, a TIP105. The base drive to the TIP105 is supplied through resistor R5. The base of the TIP105 is driven from Vz terminal at pin 9, which is the anode of a 6.2-V zener diode that connects to the emitter of the uA723 output control transistor. Circuit diagram : 15-V 1-A Regulated Power Supply Circuit Diagram The method of providing the positive feedback required for foldback action is shown. This technique introduces positive feedback by increased current flow through resistors R1 and R2 under short-circuit conditions. This forward biases the base-emitter junction of the 2N2907 sensing transistor, which reduces base drive to the TIP105.

We  can make a simple touch switch using only two inverter gates, two resistors, and two capacitors. The schematic diagram of the circuit is shown in the figure below. At power up, the output (of U1A) will be high, and the inverting output will be low because U1A gate will be triggered to ground level by C2. After triggered, the low level of U1A input is maintained by U1B output via R2. Toggle Touch Switch Using Two Inverter Gates Circuit Diagram If we touch the pad at this condition, where the output is high, then the U1A input will go high because we “short” the voltage of C1 to the input pin, and the low level previously caused by low level of U1B output voltage connected via R2 can’t be maintained because our skin resistance is much lower than 10M. After U1A input goes high then U1A output will go low, and now U1B will go high to maintain high voltage level of U1A via R2, so we can release our finger without loosing the last state. Touching the pad again after we release our pr...

Samsung has officially introduced the smartphone Galaxy A3 and A5, made ​​as stressed developers in the "full metal Unibody-body." New focus on young people and will go on sale in November. The cost of the devices has not yet been disclosed. Samsung Galaxy A5 is equipped with a 5-inch Super AMOLED display with a resolution of 1280 × 720 pixels, 4-core processor with 1.2 GHz, 13-megapixel primary and a 5-megapixel front camera, 2 GB of RAM and 16 GB of internal memory, microSD slot . The dimensions of the device are 139 × 70 × 6,7 mm, weight - 123 grams. The model runs Android 4.4 and is equipped with a battery capacity of 2300 mAh. The battery life, the Samsung Galaxy A5 did not specify. Galaxy A3 differs from the older "colleagues" reduced to 4.5-inch display with a resolution of 960 × 540 pixels, 8-megapixel main camera and half the amount of RAM. Sourced By : Makemoneyfreewithus

You've electric shock?? .. Well, .. it was nice to recover all your gout! Sometimes true .. but we often do not touch circuit accidentally in the work that is still connected with line / grid (pln) .. pissed, wants I think we stepped on the stuff ..! patient first.  Is there any easy way to avoid electric shock in repair work .. can even avoid the occurrence of ESD, if we deal with electronic goods which are sensitive to ESD (PC motherboards, mobile phones, circuit digital etc). you raft just like this series .. used as supply for the solder, when dealing with components which are sensitive to ESD and touch (CMOS IC). the greater capacity of the transformer Ampere. the greater the (good) power which can be handled. The second transformer is identical / similar.

I have just recently had solar pv installed, mainly to future proof my energy costs, I do not expect it to be like drilling for oil in my back garden, however the return looks to be encouraging. The install gives you another single unit meter, from this you will see the total amount the panels produce, but that is about it. I wanted to know how much the production was as it was happening, I discovered the light blinks on the front of the meter will flash 1000 times for each kWh of electricity which passes through. The rate of the flashing of the LED tells you how much power is currently passing through the meter. [ ]

This is a simple 741 Timer Circuit Diagram. In this circuit Rl and R2 hold the inverting input at half supply voltage. R4 applies feedback to increase the input impedance at pin 3. Pin 3, the nonin-verting input, is connected to the junction of R3 and C. After the switch is opened, C charges via R3. When the capacitor has charged sufficiently for the potential at pin 3 to exceed that at pin 2 the output abruptly changes from 0 V to positive line potential. If reverse polarity operation is required, simply transpose R3 and CR3 and C can be any values. Time delays from a fraction of a second to several hours can be obtained by judicious selection. The time delay—independent of supply voltage —is 0CR seconds where C is in farads.   Build a 741 Timer Circuit Diagram

 At this point is a Solar Charger Circuit to is used to charge information Acid otherwise Ni-album batteries using the solar energy power. The circuit harvests solar energy to charge a 6 volt 4.5 Ah rechargeable battery in favor of various applications. The stallion has Voltage and Current supervision and terminated voltage restrict sour facilities. Circuit uses a 12 volt solar panel and a changeable voltage supervisor IC LM 317 . The solar panel consists of solar cells each one rated on 1.2 volts. 12 volt DC is presented from the panel to charge the battery. Charging current passes through D1 to the voltage watchdog IC LM 317. By adjusting its Adjust pin, output voltage and current can subsist regulated. VR is placed amid the adjust pin and ground to provide an output voltage of 9 volts to the battery. Resistor R3 confine the charging current and diode D2 prevents discharge of current from the battery. Transistor T1 and Zener diode ZD conduct yourself having the status of a stop ...

This circuit has been very useful in filling a header tank for a reticulated water supply on a farm. Eight troughs are supplied in different paddocks where a lack of water would have serious consequences for the stock. In the past, the tank had been filled daily by a time clock which was not successful. During hot weather, the stock would empty the tank on a regular basis and then be without water for several hours or the tank would overflow and flood the area if the weather was wet and the cattle did not drink much.1 Automatic Water Tank Filler Circuit Diagram Automatic Water Tank Filler Schematic Circuit Diagram The circuit described has been used to maintain the level of water in the header tank within prescribed limits. It controls a 3HP submersible bore pump which has a high starting current, necessitating a solid-state relay sufficient to take the starting load. Two Darlington transistors, Q1 & Q3, in conjunction with Q2 & Q4, are connected to the upper and lower water se...

This Simple Emergency Light and Alarm Circuit Diagram is permanently plugged into a mains socket andNI-CD batteries are trickle-charged. When a power outage occurs,the lamp automatically illuminates. Instead of illuminating alamp, an alarm sounder can be chosen.When power supply is restored, the lamp or the alarm isswitched-off. A switch provides a “latch-up” function, in orderto extend lamp or alarm operation even when power is restored.Circuit operation:Mains voltage is reduced to about 12V DC at C2`s terminals, bymeans of the reactance of C1 and the diode bridge (D1-D4). Thusavoids the use of a mains transformer.   Simple Emergency Light and Alarm Circuit Diagram Trickle-charging current for the battery B1 is provided by theseries resistor R3, D5 and the green LED D6 that also monitorsthe presence of mains supply and correct battery charging.Q2 & Q3 form a self-latching pair that start operatingwhen a power outage occurs. In this case, Q1 biasing becomespositive, so this tr...

This simple key-operated gate locking system allows only those persons who know the preset code to open the gate. The code is to be entered from the keypad within the preset time to operate the motor fitted in the gate. If anyone trying to open the gate presses a wrong key in the keypad, the system is disabled and, at the same time, sounds an alarm to alert you of an unauthorized entry. Figs 1 and 2 show the block and circuit diagrams of the key-operated code locking system, respectively. Connect points A, B, C, D, E, F and ground of the circuit to the respective points of the keypad. Keys S7, S16, S14 and S3 are used here for code entry, and the remaining keys are used for disabling the system. It is very important to press the keys in that order to form the code. To start the motor of the gate, press switches S7, S16, S14 and S3 sequentially. If the keys are pressed in a different order from the preset order, the system will lock automatically and the motor will not start. Fig. 1: Bl...

The car cigarette lighter socket does not only light cigarettes, but can be utilized as an electrical channel for powering tools to work on the car such as laptops and other electronic devices. The following circuit diagram shows a way of powering a two-way mobile radio using the LM317 T voltage regulator . The LM317 T is an adjustable 3-terminal positive voltage regulator that efficiently provides a load current of 1.5 Amps over an output range of 1.2 V and 37 V. With reference to the circuit, it can accept 14 volts without any hassle and the voltage can be controlled easily with the use of a potentiometer, a 3-terminal resister with sliding contact. The whole circuit will contain the following components:  Printed Circuit Board (PCB) Resistor 1 (R1): 270 ohms Resistor 2 (R2): 2K carbon potentiometer Capacitor 1 (C1): 100nF Capacitor 2 (C2): 1uF tantalum LM317T Voltage Regulator Heat Sink DC Power Jacks Green LED: Power Red LED: Over Voltage Zener Diode: over voltage LED switch Th...

Varactor (or “varicap”) diodes are used primarily in radio-frequency (RF) circuits to provide a capacitance that can be varied by changing the applied voltage. These types of diodes often are used for tuning circuits, such as RF oscillators and filters found in wireless applications like wireless microphones and radios. Designers, then, should know about the benefits of using a nonvolatile digital-to-analog converter (DAC) to provide the biasing voltage of a varactor diode used as a voltage-controlled capacitor. The varactor diode is operated under reverse bias, which creates a depletion zone around the P-N junction. Changing the level of the reverse bias changes the thickness of the depletion region and, thus, the effective capacitance of the diode. Increasing voltage causes a decrease in capacitance. Varactor diodes are specified with a nominal capacitance value and the range of capacitance that can be achieved with a maximum and minimum voltage level. Increasing the bias voltage ran...

This RF amplifier circuit diagram is a very simple and is designed to work for 10 meters band (26 ... 30 MHz) reserved for amateurs. By making this RF amplifier small power transmitters of 200 mW, can be transformed into a power transmitters reasonable, ranging between 2 and 3 W. The circuit is very simple. Network output filter suppresses noise by at least 55 dB. Simple RF Amplifier Circuit Diagram Amplifier is suitable for almost all types of transmissions, because of the possibility of adjusting the drain current of FET's by P1. For linear applications (AM and BLU), drain current must be adjusted to 20 mA. If is used for FM-CW, P1 will be adjusted so that no current will not flow through the drain rest. For this case, the idle current is 200 mA and between 300 mA. Coils are made on cases with a diameter of 9 mm. Care should be taken to wound as tight turns without any space between them. Coils should be made as follows: L1 = 12 turns enamelled 0.6 mm copper, L2 and L4 = 5 turns ...

There is a whole lot of themes available for the iPhone and iPad on the Cydia repository. Unfortunately most of them are actually darn ugly – like really ugly. I don’t know what people are thinking when they pay for these awful themes. As always though, there is one or two which deserve a lot of attention due to the amount of time, effort and craftsmanship put into them. One of my all time favourite Cydia themes is TheCircles. However if you’re looking for a free theme which has pixel perfect icon designs, Circles is for you. Jackie Tran (only if his surname was Chan) from Prague, Czech Republic, has released what I personally think is the best free theme available for the iPhone and iPad. It’s perfectly made for both the iPhone and iPad retina displays with the iPhone icons in the size of 114×114 and the iPad icons in the size of 144×144. The amount of detail put into each icon is really incredible – even the shadows behind the icons are adjusted to make it look like they’re floating ...

This is an efficient flyback driver for modern cylindrical rectified television flybacks. Many sites doesn't provide circuits driving these transformers, they simply say that they are bad. I don't agree. In fact I built this circuit. I spent a lot of time for finding resonant frequency (around 15Khz) and duty cycle. These transformers best work at around 90% duty cycle. You may notice corona breakdown at terminals and pfffff sound (as well as the ozone smell) when adjusting the off time trimmer to near 500-300 ohms. Of course it will work for other tipes of flyback as frequency and duty cycle have a large range.  Flyback Transformer Driver Circuit Diagram Frequency range can be increased using multiposition switch for other values of C3 capacitor ,for example 2 nF for 80KHz-200000KHz, but didn't found flybacks with so high resonant frequencies, in addition with higher values of c3 , eg 200nF, 2uF the frequency will drop making possible the use of ignition coils, and rectifi...

This Auto Anti-Hijack Alarm Circuit Diagram was designed primarily for the situation where a hijacker forces the driver from the vehicle. If a door is opened while the ignition is switched on - the circuit will trip. After a few minutes delay - when the thief is at a safe distance - the Siren will sound. Where it differs from the first two alarms - is in what happens next. I'm obliged to Victor Montanez from the USA who suggested that the engine cut-out should not operate - until the vehicle comes to a stop. That way - the engine will not fail suddenly or unexpectedly. And the hijacker will retain control. I haven't been able to implement Victor's excellent suggestion completely - because I couldn't think of a simple, reliable and universally applicable way of sensing when the vehicle has come to a stop. Instead - I have postponed engine failure until the ignition is switched off. Once the thief turns off the ignition - the engine will not re-start. Clearly - there is ...