High Impedance amplifier circuits

Mini High Impedance Amplifier is an amplifier with 1 Watt and have a very high input impedance. The series amplifiers can have a very high input impedance because the use of two transistors in the input that is placed Darlington. Input impedance circuit amplifier achieves 20M Ohm. Mini High Impedance Amplifier circuit uses four transistors and an IC 741. Gain amplifier with high input impedance , we can provide the input signal from device with weak levels though.

Mini High impedance amplifier circuit is very cheap to make and quite simple. This amplifier circuit use 9VDC power supply.

Flash Lights with HT2014L

This scheme is almost the same with a flash light with LM3909. In this scheme only requires IC HT2014L as a leader, and a resistor and LED. For voltage here need ration power around 4.5 V. You can apply this series to a wider scale in comparing the use IC LM3909. For the scheme are below:

Phone Ring Generator Using Switching Supply

Phone Ring Generator Using Switching Supply Circuit

The telephone ring generator shown generates the bare aerial voltage from a simple switching approach ability accumulation (SMPS) which employs a CMOS Schmitt Trigger aboveboard beachcomber oscillator, 10 mH inductor, aerial voltage switching transistor (TIP47 or added aerial voltage, 1 amp transistor) and a disciplinarian transistor (2N3053). The inductor should accept a low DC attrition of 1.5 ohms or less. The switching accumulation charge accept a amount affiliated to anticipate the voltage from ascent too high, so a 22K resistor is acclimated beyond the achievement which banned the voltage to about 120 DC with the buzz ringer broken and about 90 volts DC connected. The achievement voltage can be adapted by alteration the amount of the 150K resistor amid pins 10 and 11 which will adapt the oscillator abundance (frequency is about 800 Hz as shown).

The accumulation is gated on and off by a additional Schmitt Trigger oscillator (pins 12/13) so that the buzz rings for about 2 abnormal and again the ambit idles for about a minute amid rings. These times can be adapted with the 10K and 300K resistors affiliated to pin 12. The advance button apparent is acclimated to manually arena the phone. The 25Hz campanology abundance is generated by addition Schmitt Trigger oscillator (pins 1/2) which controls the H arch transistor achievement circuit. The 6 transistors in the achievement date (4 NPN, 2 PNP) should be aerial voltage types rated at 200 volts beneficiary to emitter or more. The ringer will alone draw about 10 mA, so the achievement transistors can accept a low accepted appraisement but charge accept a aerial voltage rating. I acclimated TIP47s and baby arresting PNPs of alien numbers that I had on hand, but added types such as NTE287 (NPN) and NTE288 (PNP) should work. Both accept a 300 volt C-E appraisement and amount about $0.95 from mail adjustment houses.

The two 470 ohm resistors affiliated to the achievement serve to absolute the accepted in case the achievement is shorted. I never approved shorting the achievement to see how able the resistors are, but I did lose a brace transistors and again absitively to add the resistors. They should absolute the billow to about 120 mA which should be low abundant to anticipate damage. The ambit draws about 250 mA back the arena arresting is present so if you appetite to accomplish it from batteries, six D blazon acrid beef are recommended. It apparently wont assignment with a baby 9 volt battery.

IC555 Tester Circuit Diagram

555 timer tester is a simple circuit that serves to test the condition of IC 555. 555 timer circuit tester, in principle, start the timer 555 in astable multivibrator mode. As an indicator of the status of the timer 555 good condition or damaged to use 2 pieces LED which will light up in a blink alternately when the timer 555 in good condition. And only one will turn on or off all the timer 555 when the condition is broken. 555 timer circuit tester is powered using 9 Volt DC voltage source.

How to use 555 timer tester is in conjuction with IC 555 to test the existing IC socket according to the order button. Then activate the power switch to begin testing the 555 timer ic. Then live we observe the LED indicators 2buah before, whether flashing alternately (good) or not blink or even die all (timer 555 damaged).

Rain Detector Circuit

Rain Detector Using 555 is a simple alarm that can be used to find out when rain was came. Rain Detector Using In principle this is an a stable multivibrator 555 which is prepared by IC555 with a sensor attached that can detect water. A stable multivibrator with the 555 is set in the audio frequency with a frequency of 1 KHz. Rain Detector circuit 555 can be supply with voltage source that is free enough from 5-15 VDC.

Circuit Rain Detector can be mounted on motorcycle, car or other object that we want to protect from rain. Water sensor used in the circuit  Rain Detector Using IC 555.  We can make with a PCB that we make the path as shown in the image above by using aluminum foil  board or insulator boards.

1 5V Amplified Ear Circuit Diagram

1.5V Amplified Ear Circuit Diagram

Device purpose:

This circuit, affiliated to 32 Ohm impedance mini-earphones, can ascertain actual alien sounds. Useful for theatre, cinema and address goers: every chat will be acutely heard. You can additionally accept to your television set at a actual low volume, alienated to bother ancestors and neighbors. Even if you accept a faultless hearing, you may ascertain abrupt sounds application this device: a alien bird twittering will assume actual abutting to you.

Circuit operation:

The affection of the ambit is a constant-volume ascendancy amplifier. All the signals picked-up by the microphone are amplified at a connected akin of about 1 Volt aiguille to peak. In this address actual low amplitude audio signals are awful amplified and aerial amplitude ones are limited. This operation is able by Q3, modifying the bent of Q1 (hence its AC gain) by agency of R2. A noteworthy affection of this ambit is 1.5V array operation. Typical accepted drawing: 7.5mA.

Notes:

• Due to the constant-volume control, some users may consider P1 volume control unnecessary. In most cases it can be omitted, connecting C6 to C3. In this case use a SPST slider or toggle switch as SW1.
• Please note the stereo output Jack socket (J1) connections: only the two inner connections are used, leaving open the external one. In this way the two earpieces are wired in series, allowing mono operation and optimum load impedance to Q4 (64 Ohm).
• Using suitable miniature components, this circuit can be enclosed in a very small box, provided by a clip and hanged on ones clothes or slipped into a pocket.
• Gary Pechon from Canada reported that the Amplified Ear is so sensitive that he can hear a whisper 7 meters across the room.
  He hooked a small relay coil to the input and was able to locate power lines in his wall. He was also able to hear the neighbors stereo perfectly: he could pick up the signals sent to the speaker voice coil through a plaster wall.
  Gary suggests that this circuit could make also a good electronic stethoscope.

Some Type of Resistors

Much types of Resistors, is the most commonly used of all electronic components. There are different types of resistors are available with their primary function is to limit the current through the electrical circuit and to lower the voltage. Resistors are "Passive Components", which does not
contain a source of strength / reinforcement, but only weaken or reduce the signal voltage there are past them. When used in circuits generated DC Drop Voltage terminal was measured in both legs.

Resistor produces a voltage drop when an electric current flowing through it in accordance with Ohms Law, with different values ​​on each of resistor produces different values ​​of currents or voltages. This is very useful in electronic circuitry to control or reduce both current and voltage generated after flowing through it.

There are different type of resistors and manufactured in various forms because of certain characteristics and accuracy in accordance with the specific application fields, such as the High Stability, High Voltage, High Current, etc., or used as general purpose resistors where their characteristics are less of a problem. Some common characteristics associated with low resistor such as; Temperature Coefficient, Coefficient Voltage, Noise, Frequency Response, Power and Temperature Rating, Physical Size and Reliability.

On all Electrical and Electronic Resistors circuit illustrated with a line that "zig-zag" with the inclusion of the value in units of Ohms, Ω.

1. Carbon Composition Resistors - Made from carbon powder for low power / small watts.

Carbon Resistors is the Composite Resistors that most common for use in the use of any electronic circuit common and is considered the most expensive resistors. Its resistive element is made from a mixture of carbon powder or carbon graphite (like pencil leads) with ceramic (clay). The ratio of carbon to determine the overall value of resistive ceramic mixture and the higher this ratio the lower the resistance value. The mixture is then formed into a cylindrical shape and metal wire / conductor attached to each end, to provide electrical connections before the outside is coated with insulating material and color-coded signs.

Carbon Composite Resistors have a low to medium power with a low inductance which makes it ideal for high frequency applications, but has a weakness at the level of noise (high noise) and less stable in hot conditions. Identification of carbon composite resistors are prefixed with "CR" (eg CR10kΩ) and is available in Path E6 (± 20% tolerance), Panorama of E12 (± 10% tolerance) and the Panorama of E24 (± 5% & ± 2% tolerance) resistor type generally it has a power of 0.125 or 1 / 4 Watt to 2 Watt.

2. Metal Film Resistors or cermets resistors - Made of conductive metal oxide paste, for very low power

"Film Resistors" consists of Metal Film, Carbon Film and Metal Oxide Films, which is typically made ​​by depositing a pure metal coating, such as nickel, or oxide films, such as tin-oxide, the ceramic insulator rods or substrate. Resistive value of resistor is lowered by the thickness of the film were then given a helical groove by using laser light. This raises the effect of increasing the resistance because the conductive layer or a helical cut in the same result by wrapping the wire in coil form. This manufacturing method allows for the resistors of this type has a higher accuracy than the Carbon Resistor.

Metal Film Resistors have a much better temperature stability than carbon resistors are equal in size the level of noise / low noise and generally better for high frequency or radio frequency applications. Metal Oxide Resistors better capability in high waves with a much higher temperature capability than equivalent metal film resistors. Other types of film resistors is commonly known as the Thick Film Resistors made by superimposing a thicker conductive paste of ceramic and metal, called cermet, the alumina ceramic substrate. Such resistors are used in the manufacture of small electronic circuits such as in the manufacture of PCBs for Calculator, mobile phones and computer peripherals devices la. Has a temperature stability, low noise, and the proper voltage. Metal Film Resistors begins with the notation "MFR" (eg MFR100kΩ) and CF for Carbon Film types. Metal film resistors are available in the trajectory E24 (± 5% & ± 2% tolerance), E96 (± 1% tolerance) and E192 (± 0.5%, ± 0.25% & ± 0.1% tolerance) with the power of 0, 05 (1 / 20) Watt up to 1 / 2 Watt. In general, precision film resistors are low power components.

3. Wire Wound Resistors - With a metallic body as a heat absorbers, have a very high value of watts

Other types of resistors, wire wound resistors are called, are made by winding a thin wire metal alloy (Nichrome) or wire type of to ceramic insulators in the form of a spiral helix that is similar to Film Resistors. Resistors of this type are generally only available Ohm very low with high precision (from 0.01 to 100kΩ). These resistors are widely used in the instrument gauges on a Whetstone bridge circuit. This resistor also able to handle the electrical current is much higher than others with Ohm resistor the same value with a power rating of more than 300 Watts. Resistors of this type are called "Chassis Mounted Resistors". They are designed to be physically mounted on a heatsink or metal plate to further remove the heat generated thereby enhancing the ability of a current greater.

Wire wound resistor of this type begins with the notation "WH" or "W" (for example; WH10Ω) and are available in packs Aluminum Cladded (WH) with accuracy (± 1%, ± 2%, ± 5% & ± 10% tolerance) or the vitreous Enamelled W package (± 1%, ± 2% & ± 5% tolerance) with 1W power up to 300W or more

4. Semiconductor Resistors - Resistors for working at high frequency and precision.

Thats some type of resistors are widely used in everyday life, especially in the electronics field.

SAMSUNG protect circuit with LA76931

Following is the protect circuit Samsung TV which use IC LA76931 as basic working the protect circuit. This Protect Circuit LA76891 located at pin-30 whichconnected to the collector of transistor Q902.In normal conditions the voltage at the base of Q902 is "low" and the voltage at pin-30 is "high". For the temporary crippling protect, it can be removed Q902 (or to the emitter-base short).

SAMSUNG protect circuit with LA76931

Sampling circuit protect from:

Vertical Protect. Pulses of the vertical-out rectified by diode D355, so that the base voltage is approximately 0.6V Q904 ,and collector voltage is 0v.

X-ray Protect (option). Sampled using a heater voltage of the circuit as shown below. Normal vltage in x-ray path to the base of Q902 is zero.

ABL protect. If there is damage to flyback voltage which can cause a high rise ABL, then protect circuit will actively work.

Mosfet Amplifier with power output 400W

See figure below its power amplifier using transistor mosfet as amplifier.

Mosfet Amplifier with power output 400W

Multiplexer

Multiplexer is an electronic circuit that functions to select one among many inputs into one output. The number of bits from the selector (selector) to determine the number of input channels can be received.
With provisions are:

I = 2 ^ s

where:
I: Number of input channels can be received
s: The number of bits of the selector or the number of lines of voters

for example if we want the 14 input channels, then the minimum number of bits of selectors who should we meet is 4 bits. Where is the selector 4 bits can represent 16 channels of input.

Protectors Circuit on SMPS power supply

The simplest example SMPS which still uses 3 transistors (C3807, A1015 and power transistors) classic problem that often occurs is: - Problem in the feedback circuit can cause the output voltage B + over so that it can endanger the aircraft as a whole. For example elco erupted, pcb burnt burnt by over-heated, horizontal transistor short.

- Problem on feedback circuits may cause power regulator transistor is damaged due to over current transistor (eg, due to the 47k resistor transistor circuit on the secondary error detector value is delayed).

- If the input ac voltage drops can cause the power regulator transistor is damaged, due to over current transistor If the secondary there is a power transistor short can cause damage over current regulator.

- Protectors are designed to make the SMPS SMPS "reliable will not be damaged" if there are things that go wrong as mentioned above. 

SMPS Circuit

SMPS circuit using IC systems generally are designed with a surge protector, which include:

• Over voltage protector (OVP)
• Over current protector (OCP)
• Over load protector
• Short circuit protector
• Over temperature protector
  

Schematic Audio Amplifier Circuit 200W

Output Power : 200Watts
Load Resistance : 8ohms
Input impedance : 55K
Maximum supply voltage : (+95v)-0-(-95v)
Recommended supply voltage : (+66v)-0-(-66v)

This complete aerial quality, low babble address audio ability amplifier is based about the Hybrid Integrated Ambit STK4050 bogus by Sanyo. The ambit incorporates aggregate and has a best music achievement ability of 200W.The ambit incorporates an on lath ability supply; therefore, alone centre broke agent is appropriate to ability the circuit. I t has actual acceptable affection sound. U can use it with your Home Theatre your PC & etc... You can additionally use it as Subwoofer Amplifier.

It is a bunched amalgamation for THIN-TYPE Audio sets. Easy Heatsink architecture to banish calefaction generated in THIN-TYPE audio sets. Constant-Current ambit to Reduce accumulation switch-ON and switch-OFF shock noise. External accumulation switch-On and switch-OFF shock babble muting, Load circumlocute protection, thermal abeyance and added circuits can be tailored-designed.

Microcontroller Interface Engineering With ADC 0804

In ADC 0804 interface techniques with microcontrollers are pin-pin control must be controlled if we want to use the ADC with the microcontroller, there is value addition refferensi voltage to be supplied in 0804 ADC interface with a microcontroller, for example, we use the 0804 ADC (8 bit), if we give refferensi voltage 2.55 volts then we will get the increase of 1 bit to change 10 mVolt. Please note that the 0804 ADC pin on the leg that is form Vref Vref / 2, so to get a 10mV resolution is necessary for setting Vref / 2 equal to 1.275 V

The interface circuit microcontroller with ADC 0804

Mechanical interface microcontroller with ADC 0804

The steps in accessing data from the ADC 0804 by the microcontroller sebgai follows;

Enable ADC with signal 0 at the foot of Chip Select.

Give commands from conversion by providing a low pulse to the foot of the ADC Write narrow

Wait for the ADC issued a signal 0 from his leg INT

Give a moment of time delay for data from the ADC is correct

Give the read command by giving the signal 0 at the foot of ADC Read

Give a moment of time delay

Now data from the ADC is ready for use and if the microcontroller.

Tips for Choosing a quality Power Amplifier

Here are some tips you need to note:

1. Pick of the power that suits your needs. For personal use such as exercise, etc., is sufficient to choose an amplifier with a power of 15-20 watts. In most small power amplifiers are already available facilities such as Head Phone jack (eg Guitar Amplifier Laser 20) which is very useful especially for young people who have a habit of playing music until midnight. By leveraging these channels to Head Phone, then secured another household or neighbors will not be disturbed our music sound. Sound good hasilnya.Apabila amplifier system we will use to train together in a full band with drums, etc., then you should choose a larger power amplifier that is 70 watts or above. Thus the sound produced from the amplifier and sound system will not be drowned by the sound of pounding and pounding beat Drum.Untuk use on stage, you will need a higher power that is at least 125 watts or more, because this amplifier will be able to once we use as a monitor of musical instruments were playing.

2. Choose the facilities we need. Do not buy amplifiers which have facilities that we do not really need when it is increasing the price we pay. Unless the same price we can get better facilities, there is no harm in our selection.

3. Choose a good quality amplifier. If we need an amplifier to your keyboard, then it is advisable to select an amplifier that does not change the color of the original sound generated by the keyboard musical instrument they will be (flat). There are many amplifiers that produce different sounds from the original sound, if this happens there will be other voices that would reduce the original character of the actual sound produced by the keyboard because of the addition or subtraction of a particular frequency. Usually this happens at a very low frequency (low bass) or very high frequency (high treble). (Try the sound system rental, sound rental service) For amplifiers Electric Guitar and Electric Bass this (flat characteristic) does not apply because it specifically for these two types of instruments are required specificity of character frequency. Basically for Electric Guitar amplifier output is not needed for low frequency and high. For Electric Bass needed a low frequency, but not required a high frequency. We can learn from the rental place and the sound system rental-quality musical instrument.

4. Model and performance amplifier can be considered final. The desired model will depend on individual taste. A good model according to a person, not necessarily a good thing according to those who lainnya.Pada most professional musicians model will be the last option or not too overlooked. They will be more concerned with the quality and facilities of the amplifier. Maybe we can find also in the rental services professional sound and musical instrument rental place bagus.Demikian brief tips on choosing an amplifier, hopefully this can help to determine the right choice before you buy an amplifier and produce sound quality music is also of course .

Tips for Choosing Quality Amplifier

1. Pick of the power to suit your sound system. For personal use such as exercise is sufficient to choose an amplifier with 1-20watt power. In most electronic devices / small power amplifiers are already available facilities such as head phone jack (eg laser20 guitar amplifier) ​​is very useful especially for young people who have a habit of playing music until midnight. By leveraging the channel for these headphones, then secured another household or neighbors will not be disturbed "attraction" we. If the amplifier sound system we will use to train together in a group full band * with drum and band instrument, then you should choose a power amplifier 70watt or above. Thus the sound produced from the amplifier will not be drowned by the sound of pounding and pounding drum beats. For use on stage, you will require more resources than most, namely at least 125watt or more, because this amplifier will be at the same we use as a monitor of musical instruments were playing.

2. Select the facilities we need. Do not buy a multimedia system / amplifier that has the facilities that we do not really need, if it is increasing the price we pay. Unless the same price we can get better facilities, there is no harm in our selection.

3. Choose a good quality amplifier. If we need an amplifier to your keyboard, then it is advisable to select an amplifier that does not change the original color generated by the keyboard (flat). There are many Indonesian musical instrument amplifier that produces a different sound from the original sound, if this happens there will be other voices that would reduce the original character of the actual sound produced by the keyboard because of the addition or subtraction of a certain frequency speaker system. Usually this happens at a very low frequency. (Low bass) or very high frequency (high treble). To Lighting System, Electric Amplifier Electric Bass Guitar and this (flat characteristic) does not apply because it specifically for these two types of instruments required specificity of character frequency. Basically for Electric Guitar not dipelukan amplifier output for low frequencies and high. For Electric Bass needed a low frequency, but not required a high frequency.

4. Models and appearance can be thought being given to the last amplifier. The desired model will depend on individual taste. A good model according to a person not necessarily a good thing by other people.

In most professional musicians, models will be the last option or not too overlooked. They will be more concerned with the quality and features of the amplifiers for musical instruments. But if you are confused, you could just rent equipment or hire sound system rental equipment.

Rangkaian Power Supply for tube amplifier

Power supply for EL-34 tube is specially designed for the purposes of power supply at the push-pull amplifier with EL-34 tube as in article 35 Watt Tube Power Amplifier Push Pull before.
Power supply for EL-34 tube amplifier is made with transformers CT and 2 pieces diode as rectifier. Mechanical filters are applied in the power supply uses 3 levels. Power supply for tube power amplifier can deliver output voltages +220 VDC. Circuit details can be seen in the following figure.

The above power supply circuit has a high output voltage so that need to be considered in the manufacture and perakitanya because electricity can tesengat (stun). Power Supply For Tube Power Amplifier With Diode EL-34 was created specifically for the power amplifier tube push pull EL-34.

Zero Crossing Detector Circuit

Zero Crossing Detector circuit is basically an application of a comparator. In the article series Zero Crossing Detector with Op Amp is built using a comparator of an Op Amp IC741/351. The process of detection of this comparator is  0Volt input signal crossing point by making reference value at comparator 0Volt.

 The output of the Zero Crossing Detector circuit with Op Amp is wave-shaped box that detection result of the crossroads of 0 volt input signal.

Emergency Light 555

Emergency Lamp With 555 is one solution for lighting during power outages. With Emergency Lamp Series 555 uses a 12VDC voltage source that can be supplied from the 12V battery. Emergency Lamp 555 Series With these very simple and easy to make because all the components easily available in the market. Emergency Lamp Series With this 555 can turn on the light 5W-10W. The circuit is built with an astable multivibrator with the IC 555 that is used to mendrive transformer through Q1. For more details can be viewed directly from the series Emergency Lamp With 555 follows.

Working frequency range of 555 Emergency Lamp With this set of configurations R1, R2 and C2. T1 in series Emergency Lamp With 10V 500mA 555 is a transformer. Secondary part (0-10V) is connected to the Q1 to be given the signal from the multivibrator. Then the primary (0-220V) is connected to the lamp.

Audio Power Amplifier 170W with LM4651 LM4652

Audio Power Amplifier 170W with LM4651 & LM4652

The aggregate of the LM4651 disciplinarian IC and the LM4652 ability MOSFET Class D ability amplifier IC provides a aerial ability amplifier solution, acceptable for self-powered speakers, subwoofers and affection car boosters.

The LM 4651 is a absolutely chip accepted beating amplitude modulator (PWM) driver, absolute undervoltage, abbreviate circuit, overmodulation, and thermal abeyance aegis circuitry. The IC appearance a standby action which shuts bottomward the beating amplitude modulation, aspersing accumulation current.

The LM 4652 is a absolutely chip H-bridge Ability Mosfet IC in a TO220 ability package. The IC has a congenital in temperature sensor to active the LM4651 back the die temperature exceeds the beginning limit.

Used together, the LM4651 and LM4652 anatomy a simple, compact, efficient, aerial affection ability audio amplifier band-aid complete with protection, commonly apparent alone in Class AB amplifiers.

Tips and Tricks on Audio Power Amplifier Circuit

Amplilfier power series from the beginning until now did not experience any changes. Some say this series is good, but the series was good fitting assembly and tested the results are not as we expected.

The problem is usually treble is less subtle, less sound, sound breaking, buzz, middle of the field tested the bass sound is lost. so you do not have to believe what people 100%. The quality amplifier built-up would differ greatly with the amplifier assembly, a series can be the same but the quality will depend on who manufacture it.

Here are a few tricks to try

How to cope with a buzzing sound

Power amplifiers are often used in the field blazer. This circuit is said said person is a bell assembly. But you do not immediately interested in this power, the circuit rather complicated and difficult to understand reflect the intelligence of people who first mendisainnya. In my opinion a great power is the power of simple, inexpensive, easily assembled and rational. You do not need to use expensive components such as the price of tantalum capacitors, power mosfet and the other expensive. This does not determine the quality of the power amp so that we raft. Power of sometimes causing buzzing, to overcome that is by holding the line input jack ground to the ground with 10-22 ohm resistors. So do not just take the ground input from the ground but held first with the R 10 ohms.

How to setting bias trimpot

Rotate the trimpot bias (if any) until the drain current of 50-100mA on each power transistor, in order to avoid defects treble in volume in the top position at 10. The risks are so panassss heatsink! (This setting marks on plate A-AB)

Offset trimpot setting

At the time of input without a signal, turn the trimpot so that the voltage on the speaker offsets actually read 0 volts. If you do not want to bother, use and entrust it with ic type series from Hitachi HA17741 IC brand quality or other! This is the heart of the series, 90-95% of quality is determined from the IC circuit this!

Overcoming the voice

Use pre-amp circuit to increase the signal of at least 2 times. normally and should pre-amp circuit uses IC op-amps with +12 V minimum supply-12V. Raise his mid tone!

If hard you do not want to just use the tone control circuit IC is his mid!

The secret is not in his mid tone alone, but the signal output from the IC op-amps are usually large.

Treble rupture

Excessive treble will damage the power amp, power rather than out even ngedrop. Handle, attach the filter capacitor on the input 1NF power amp to ground to ensure the signal is not disabled. Always use a quality active components such as ICs and transistors, 500 price difference will also be different results.

Use a large cable and short as possible, especially for leg power transistor, and this transistor should be directly soldered to the pcb.

Missing bass in field

Usually power for field use supplay CT 50V 50V transformer, or at least 42V 42V ct. The greater the greater the supply voltage watt channeled though the series is written only 300-400 Watts only. This course uses Elko capacitors with voltage 80-100V. 10.000uF/100V capacitor will be equal to 4X10.000uF/50V and of course voltage capacitor is filled with full / almost full.

Try to use a strong Elko at temperatures of 105 C. Capacitors are strong in supply of more than nominal voltage is written on his body. For example 4700uF/50V 85C capacitor will quickly explode in voltage 51V 85C. And Elko will be strong 105C 4700uF/50V voltage supplied more than 50V at a temperature of 85C. Elco so that it does not quickly explode if given the full voltage, keep its temperature as cold as possible, fan with the cool air.

For speaker

Try using a driver speakers that have a large spool diameter fitted with a suitable size bok. Usually included examples of the parameters / dimensions bok. Size bok bok2 usually larger than that sold in the market. if you force using bok that from this market, use driver type G12-80 (sorry no fear brand called promotion) speakers with bass tones to wall size small. Bok wall should be thick, strong and do not forget glued! Bok who will not be glued with a different sound, especially bass tones, prove it!

Heat Sensor

The form of transistor, the transistor is usually type BD139 MJE340 or it could be located in the center, flanked by a pair of transistors having a certain equal. These transistors must be mounted on the main heatsink to detect the heat generated by power transistors. It acts to lower bias currents at the hot heatsink. So what heatsink and power transistors must be set diposisi hot? Yes objectives nothing to prevent the signal from the defect (in class A or AB), with consequent heat. This class is not necessary and will not be felt if you only want the bass tones only. Goal setting on. AB grade is still crystal clear sound even though the maximum volume positioned rotated (in the middle of the field).

It is unlikely, but its closer.

Large heatsink

Not only electrolytic capacitors are more explosive at high temperatures, power transistors can also break away under stress break the original. For example 2SC5200 transistors have the break voltage of 230Vdc, but if temperaturya high voltage values ​​will break his fall well below this value, resulting in faster transistor is damaged. Use of heatsink and cooling fan is very important not only to reduce the heat, more than it can prevent the transistor from break / damaged and weakened output. Increasingly hot temperatures will be more or less ability. Use of this cooling is expected for the components remain fresh, fit and durability.

Choice Component

Power Transistor

There are so many types and models of these transistors, for example MJ15003 MJ15024-4 and-5 from Motorola, but unfortunately these components are not manufactured by Motorola again but from ON semiconductor. Transistor model jengkol usually stronger in the high temperature, probably due to more airtight. 2SC5200 from Toshiba, this transistor is equal dalamannya Sanken 2SC2922 Korea, and both will break if the temperature is too hot. 2SC2922 Sanken issued tin granules when heated, this weakness, the Japanese technology is better than Korean technology. 2SC3281, this transistor is the most popular and frequently used in professional amplifier, but Toshiba does not produce much, if still there in the market, then it most likely is fake!

Transfomer

There are two models of the transformer which is often used, namely EI model (box / conventional) and the model toroid (ring / donut). Some say the toroid transformer model is better because it has a smaller flux leak, in fact the same. Circuits that are sensitive to this flux is high berpenguatan circuits like pre-amp head and mic pre-amp. The circuit is usually installed horizontally / flat parallel to the structure of a conventional transformer wire so that a series of emails received reverberation is greater. Unlike the model toroid transformer is arranged in a vertical wire their email so that the wires are perpendicular to circuit kits The effect is the flux of the pre-amp kit receive a smaller head. To solve for this flux does not enter the series is by downloading shelding / fortified with non-magnetic plate such as aluminum plate and copper plate / sheet pcb board. Plate is of course connected to ground via a cable. To match the flux in a vertical transmission, the conventional transformer needs to be installed side (the side be side down) so that the arrangement of transformer wire stand upright, this method is often used in built-up POWER2. Voltage 50V 50V CT can be obtained by combining the two transformer 25VCT25V, CT is not used, the foot 25V 50V so that the legs be made only to CT, bringing the total number is 100V or 50VCT50V. It deserves used for pwr amp powerless over 400Watt.

Resistor 5 Watt

Resistor on the power transistor legs are usually valued at 0.5 ohm 5 Watt white square. If we dismantle dalamannya it appears there was a circular aluminum wire. It resembles the inductor, the inductive reactance inductor will be higher when fed a high-frequency fractions so that treble tone will be weakened and deformed. Power required to remove the high notes (treble) of course greater, there is a problem here. The use of R 0.5/5W on its home-based power amplifier ok-ok only. But often do not realize the cause of damage to the speakers and power amplifiers is the high treble tones. Treble is not out but was hit by a pwr amp so arising is hot and damaged. We recommend using common Watt resistor 2 12:47 - 1 ohm parallel 2 so that counted 4 Watt. Or if you use 0:22 ohm 2 Watt Resitor unnecessary because the voltage clamp diparalel quite half (one R 0.5/5W replaced one R 0.22/2W) its ok.

Fuse

Nature damage to semiconductor materials / transistor power amplifier is short, if you use a supply that is high enough then the destruction of these transistors will invite their partners to be damaged as well. In order for the destruction of this transitor congregation not need the installation of fuses. 1.5A per power transistor is considered sufficient. 

Type of pneumatic valve

Pneumatic valves have many types and functions. pneumatic valves .The role as a regulator / controller in the pneumatic system. Components such control or so-called valves (Valves). Pneumatic Valve types can be grouped according to the construction design as follows:

a. Poppet valves (Poppet Valve Pneumatic)

■ Ball Valve (Ball Valve Pneumatic Seat)

■ Disc Valves (Pneumatic Valve Seat Disc)

b. Slide valve (slide valve Pneumatic)

■ Longitudinal Slide

■ Slide Plate

Meanwhile, according to its function valves are grouped as follows:

a) Valves Steering (Directional Control Valves)

b) One-way Valve (Non Return Valves)

c) Regulatory Pressure Valve (Pressure Control Valves)

d) Flow Control Valves (Flow Control Valves)

e) open-close valve (Shut-off valves)

While the arrangement order in the pneumatic system can be described as follows:

■ The input signal or input element gets energy directly from

power source (air felts) are then transmitted to the processor

signal.

■ The signal processor or processing element signal processing

logic inputs are to be forwarded to the fi nal control element.

■ end of the control signal (final control element) that will drive the direction of movement of the actuator output (working element) and this is the end result of the pneumatic system.

- Pneumatic-Valve Types

Digital Volume Control Circuit using MAX5486

A channel digital volume circuit on IC MAX5486 is shown here. MAX5486 40K digital volume / balance controller that pushbutton interface. The IC bias voltage that eliminated of an external circuitry for purpose and thereby by reduces external count. The IC has an LED indicator driver circuit be used for driving the indicator LEDs indicates level and balance level. The IC operated from or power and in pin TSSOP package. circuit on MAX5486 applied applications like personal audio systems, audio devices, home theatre systems, audio systems, audio systems etc.

The right channel input is applied to the pin8 (high terminal (HR) of internal digital potentiometer of the IC) and left channel input is applied to the pin17 (high terminal (HL) of the second internal digital potentiometer of the IC). Low terminals (pin and 6) of potentiometers are shorted and connected to the mid bias voltage output (pin11) of the IC. at the buffered wiper terminal (pin10) of internal potentiometer and left channel output at the buffered wiper terminal of the second internal potentiometer of the IC. A 1uF capacitor is connected from the bias generator bypass (pin12) to ground. of this capacitor is noise bypassing. of capacitors C4 and C5 are to bypass noise from the VDD and VLOGIC sources. This improves stability and performance of the circuit.

LEDs D1 to D5 are the indicator LEDs indicates volume and balance levels. R1 to R5 limits current through the corresponding LEDs. 1M resistor R6 for activating the indicator LED drivers. LED D6 represents operation mode of IC. When it glows, the IC is in balance mode and when off, the IC in volume mode. Resistor R7 limits through LED D6. volume mode the LEDs work a bar graph indicating volume. balance mode, the centremost LED alone glows when a centred balance. mute mode, all indicator LEDs OFF.

Push button switches S1 to S4 are used for controlling the circuit. Pressing S1 push the IC into mute mode. Push button S4 used between volume mode and balance mode and LED D6 indicated it. Push button S2 and S3 are used for increasing and decreasing volume mode and shifting the balance to left and right balance mode. The Vss pin of the IC is grounded single operation circuit. Shutdown pin (pin6) is tied to the VLOGIC for disabling the shutdown . Connecting the shutdown pin to drive the IC to the shutdown mode.

The output of the MAX5486 is sufficient enough to drive high impedance headphones. For driving low impedance headphones or speakers an amplifier stage be added to the output. power dissipation of MAX5486 is 675mW and consider this point while selecting the loads.

FM RADIO RECIEVER

This simple FM radio receiver circuit consists of a regenerative rf stage, TR1, followed by a two of three-stage audio amplifier, TR2 to TR4. In some areas 3 stages of audio amplification may not be necessary, in which case TR3 and its associated components can be omitted and the free end of capacitor C5 connected to the collector of TR2.

Circuit Diagram

The critical part of the fm radio receiver is the first stage, TR1/VC1, where the wirings must be kept as short as possible. Coil L1 is formed by winding 8 turns of 1mm (20 swg) enamelled copper wire on a 6 mm diameter former, which is then removed. After that L1 should be stretched carefully and evenly to a length of about 13mm.

Transistors List

TR1 = BF199

TR2 = TR3 = TR4 = BC547

The tunning capacitor VC1 is one of the two fm sections of a miniature fm transistor radio with built-in trimmers (VC2). The “earthy” end (moving vanes and spindle) is connected to the 22pF capacitor C1. The value of the rf choke L2 is not critical, anything from 1µH to 10µH being suitable.

The output is suitable for ordinary earphones connected in series to provide an impedance of 64Ω.

Tuning in the FM radio receiver

To operate the radio receiver, potentiometer VR1 must first be advanced slowly (towards the end of the track connected to battery positive) until, at about the half-way point, a sudden slight increase in background noise will be heard, indicating the onset of oscillation. It then should be backed off, very slowly, until oscillation just stops; it then should be possible to tune in some stations.

The correct frequency range of 87 MHz to 108 MHz can be obtained by adjusting VC2 at the high frequency (108 MHz) and slightly stretching or squeezing together the turns of coil L1 at the end (87 MHz).

SWITCH DEBOUNCING CIRCUIT

Switch debouncing is one of those things you generally have to live with when playing with switches and digital circuits. If you want to input a manual switch signal into a digital circuit youll need to debounce the signal so a single press doesnt appear like multiple presses. This circuit will remove the transient spikes and contact bounces from a non-latching push button switch.

Circuit Diagram

Notes

Using a 555 timer as a monostable circuit, it is easy to build a good switch debouncer circuit. There are many circuits for SPDT debouncing, but not many for a normally open, push-to-make press button switch (PBS). The 555 monostable gives an output pulse of around 20 ms with component values shown. The formula for determining the output pulse is:

Tout = 1.1 R1 C1

With the values in my circuit this equates to :

Tout = 1.1*1.8*106*10*10-9 = 0.0198 sec or 19.8 ms

The 555 circuit can be re-triggered if the input is held low longer than the output pulse. To prevent this happening, I have included a further timing circuit comprised of the 1Meg resistor and 47n capacitor. Normally, the 47n capacitor is discharged via the 1 Meg resistor. When the switch is pressed the capacitor quickly charges and provides a brief negative pulse to the 555 input. When the capacitor is fully charged, the potential across the voltage divider formed by the 10k and 1Meg resistors is insufficient to retrigger the monostable. Releasing the switch quickly discharges the capacitor. The output of a 555 monostable is suitable for connecting to TTL and CMOS logic circuits.

741 op amp bassed Alarm project electronic circuit with explanation

A very simple alarm project electronic circuit can be designed using a common 741 operational amplifier IC and some other common electronic parts . As you can see in the schematic circuit , this alarm project is activated by some normal open contacts , connected in parallel . If one of those contact is closed the alarm will sound .
This alarm project is composed from an audio frequency generator , a small audio amplifier stage and a small command stage .

The audio frequency generator is designed using a 741 operational amplifier ( or some other similar type ) .The T2 and T2 transistors forms a small audio amplifier and the normal opened contacts I1to I3 forms the command stage ( you can use how many contacts you need ).
In stand-by mode when all contacts are opened T1 transistor is locked and the alarm is inactive . If one of the contact is closed T1 transistor will activate the relay that will activate alarm . One the alarm starts to sound it can not be stopped until the I contact will be opened ( the circuit will be unplugged from the power source) .

The relay used in this project must have a 12 volts nominal voltage ( 10 volts activation) with a maximum working current of 10-30mA.
This circuit project must be powered from a 12 volt DC power supply .

Fluorescent Light Wiring Diagram Tube Light Circuit

This post "Fluorescent Light Wiring Diagram | Tube Light Circuit" is about how to wiring fluorescent light and "how a Fluorescent Tube Light works". The wiring process of fluorescent tube lamp/light with Ballast,Starter is quite easy and simple. In most cases when we buy a fluorescent light it comes in a complete set with all wire connected. If you want do it yourself (DIY), you can buy all the parts individually. And you can complete all connection of the fluorescent light/lamp with the help of this wiring circuit diagram.

Fluorescent Light Wiring Diagram

Fig:Fluorescent Light Wiring Diagram

Main parts of Fluorescent Tube Light:

     1.Fluorescent Tube

     2.Ballast

     3.Starter

     4.Holder, wire etc.

How Fluorescent Lights works:

The starter is like a key of fluorescent light because it is used to light up the tube. When we connect the AC supply voltage to the circuit, then the starter act like short circuited and current flow through those filament (located at the first and second end of the tube light) and the filament generate heat and it ionized the gas (mercury vapor) in the fluorescent tube lamp. So the gas becomes electrically conductive medium. At the same time when the starter opened the circuit path of two filaments from series connected, then the ballast release its stored voltage. And it makes the fluorescent tube fully lighten. Now the starter has no job in the circuit, if you open it from the circuit the fluorescent tube light will be still lighten, until you release the main supply. 

LB1948M bassed forward reverse motor control driver circuit with explanation

A very simple forward reverse motor control driver electronic circuit project can be designed using the LB1948M 2 channel low saturation voltage forward reverse motor control driver IC. LB1948M motor driver is optimal for motor drive in 12V system products and can drive either two DC motors, one DC motor using parallel connection, or a 2-phase bipolar stepping motor with 1-2 phase excitation mode drive.
Some features of the LB1948M motor driver IC are : 12V power supply ,low saturation voltage: VO(sat) = 0.5V (typical) at IO = 400mA ,zero current drawn in standby mode , braking function ,built-in thermal shutdown circuit .

The LB1948M can be used as a single-channel H-bridge power supply by connecting IN1 to IN3, IN2 to IN4, OUT1 to OUT3, and OUT2 to OUT4 as shown in the figure. (IOmax=1.6A, VO(sat)=0.6V (typical) at IO=800mA) .
The circuit is very simple and require few external electronic parts .

TDA1562 bassed One IC 50W Audio Amplifier circuit

The integrated output amplifier described in this article consists of little more than one integrated circuit. It is intended especially for use in motor vehicles and other battery-operated applications. Although it appears simple and hardly worth looking at, the amplifier can produce an appreciable audio power output. The circuit diagram in Figure 2 emphasizes how few external components are needed to construct a complete output amplifier.

One-IC 50W Audio Power Amplifier Using TDA1562 circuit project

For instance, the new device does not need compensation networks to enhance the stability. Also, because of the absence of switch-on phenomena, there is no need for a switch-on delay network. There is, of course, still a need for supply line decoupling capacitors. Capacitors C5 and C6 are required for Class-H operation, about which more in the box. The value of input capacitors C1 and C2 is relatively low, thanks to the high input impedance of the IC. Switched RC network R4-C4 at the ‘mode select’ input (pin 4) serves to switch the IC to ‘mute’ or ‘standby’.

One-IC 50W Audio Power Amplifier Using TDA1562 circuit diagram

When the supply voltage is switched on, the IC is first switched automatically to the ‘mute’ mode and to ‘on’ only after a short delay. The time constant R4-C4 is a few tenths of a second and this delay between the two states is sufficient to obviate disturbing (and annoying) switch-on phenomena. Switch S1 enables the amplifier to be switched to ‘standby when the use of the amplifier is not needed for a period of time. When that time has elapsed, the amplifier is quickly reverted to normal operation. The current drain in the standby mode is virtually negligible at only 200µA. Resistor R3 prevents a short-circuit current ensuing when S1 is being closed at the instant C4 is being discharged.

One-IC 50W Audio Power Amplifier Using TDA1562 circuit

One-IC 50W Audio Power Amplifier Using TDA1562 circuit schematic

Measurement results (at Ub=14.4 V)
Supply voltage

* 8–18 V

Sensitivity

* 760 mV r.m.s.

Input impedance

* 70 kΩ

Power output

* 54 W r.m.s. into 4 Ω (f=1 kHz; THD+N=1%)

Harmonic distortion (THD+N)

* at 1 W into 4 Ω: 0.046% (1 kHz)
* 0.29% (20 kHz)
* at 35 W into 4 Ω: 0.12% (1 kHz)
* 0.7% (20 kHz)

Signal-to-noise ratio (with 1 W into 4 Ω)

* 88 dBA

Power bandwidth

* 7.5 Hz – 185 kHz (at 25 W into 4 Ω)

Quiescent current

* about 135 mA (‘on’)

Resistors:

* R1 = 1MΩ
* R2 = 4kΩ7
* R3 = 1kΩ
* R4 = 100kΩ

Capacitors:

* C1,C2 = 470nF
* C3,C4 = 10µF 63V radial
* C5,C6,C8 = 4700µF 25V radial
* (18mm max. dia., raster 7.5 mm)
* C7 = 100nF, raster 5 mm

Semiconductors:

* D1 = high-efficiency-LED
* IC1 = TDA1562Q (Philips)

Miscellaneous:

* S1 = single-pole on/off switch
* Four spade connectors, PCB mount Heatsink for IC1 (Rth<2.5 k/w)

DC Motor Speed Controller

This circuit takes advantage of the voltage drop across bridge rectifier diodes to produce a 5-position variable voltage supply to a DC fan or other small DC motor. It is not as efficient as a switch-mode circuit but it has the virtues of simplicity and no switching hash. The four full-wave bridges are connected so that each has two pairs of series diodes in parallel, giving a voltage drop of about 1.4V, depending on the load current.Circuit diagram:

DC Motor Speed Controller Circuit Diagram

The rotary switch should have "make before break" contacts which should be rated to take currents up to about an amp or so. For higher currents, higher rated bridge rectifiers and a suitably rugged rotary switch (or solenoids) will be required. If you want smaller voltage steps, you could use the commoned AC inputs on the bridge rectifiers to give intermediate steps on the speed switch.
Author: Stephen Butcher

2005 Yamaha DT125X Wiring Diagram

Generally the 2005 Yamaha DT125X electrical system consists of CDI unit, servomotor, battery, fuse, neutral switch, thermo unit, rectifier/regulator, ignition coil and main switch.

You can find detail and complete 2005 Yamaha DT125X Wiring Diagram here on the last page of the service manual.

Rear Fog Lamp For Vintage Cars Diagram Circuit

According to current legislation in many countries, vintage cars must also be fitted with a fog lamp at the rear. In modern cars, there is a bit of circuitry associated with the fog lamp switch to prevent the fog lamp from going on when the lights are switched on if the driver forgot to switch it off after the last patch of fog cleared up. The circuit described here extends that technology back in time. The circuit is built around a dual JK flip-flop (type 4027). T3 acts as an emitter follower, and it only supplies power to the circuit when the lights are switched on.

For safety reasons, the supply voltage is tapped off from the number plate lamp (L2), because it is on even if you accidentally drive with only the parking lights on. The wire that leads to the number plate lamp usually originates at the fuse box. As the states of the outputs of IC1a and IC1b are arbitrary when power is switched on, the reset inputs are briefly set high by the combination of C1, R1 and T1 when the lights are switched on (ignition switch on). That causes both Q outputs (pins 1 and 15) to go low. IC1a and IC1b are wired in toggle mode (J and K high).

The Set inputs are tied to ground (inactive). The driver uses pushbutton switch S1 to generate a clock pulse that causes the outputs of the flip-flops to toggle. The debouncing circuit formed by C2, R4 and T2 is essential for obtaining a clean clock pulse, and thus for reliable operation of the circuit. C1 and C2 should preferably be tantalum capacitors. The Q output of IC1b directly drives LED D1 (a low-current type, and yellow according to the regulations). The Q output of IC1a energises relay Re1 via T4 and thus applies power to the rear fog lamp L1.Circuit diagram:

Rear Fog Lamp Circuit Diagram For Vintage Cars

Free-wheeling diode D2 protects T4 against inductive voltage spikes that occur when the relay is de-energised. In older-model cars, the charging voltage of the generator or alternator is governed by a mechanical voltage regulator. These regulators are less reliable than the electronic versions used in modern cars. For that reason, a Zener diode voltage-limiter circuit (D3 and R9) is included to keep the voltage at the emitter of T3 below 15 V and thus prevent the 4027 from being destroyed by an excessively high voltage.

The supply voltage for the circuit is tapped off from the fuse box. An accessory terminal is usually present there. Check to make sure it is fed from the ignition switch. The pushbutton switch must be a momentary-contact type (not a latching type). Ensure that the pushbutton and LED have a good ground connection. Fit the LED close to the button.The following ‘Bosch codes’ are used in the schematic:

• 15 = +12 V from ignition switch
• 58K = number plate lamp
• 86 = relay coil power (+) IN
• 85 = relay coil power OUT
• 30 = relay contact (+) IN
• 87 = relay contact OUT

Author: Eric Vanderseypen - Copyright: Elektor Electronics Magazine

Water Level Indicator This electronic circuit is a water level Indicator It is simple and practical measure and know the level of reservoir The com

This electronic circuit is a water level Indicator. It is simple and practical measure and know the level of reservoir. The component IC CMOS 4066 used as switcher on any level detector/sensor that connect the negative polarity pin of each LED to ground. Buzzer will be sounded if full level sensor achieved. Its a cool electronic circuit.

Features:

• Power Supply 6 - 15 volts
• Measuring four different levels
• To give voice warning about filling or emptying the reservoir, "exactly according to the delicate"
• Very small and components are cheap and available

Parts Lits:- IC CMOS CD4066
- Transistor BC148
- Resistance 330 Ohm 4x
- Resistance to 180 KOhm 4x
- Four pairs optical multi-color LED
- Small buzzer/bell 6-15 volt

Water Level Indicator in Detail

LT3433 based Step Up Step Down DC to DC Converter Circuit Diagram circuit with explanation

The illustration provides below schemes 8V-60V to 12V Converter Circuit Diagram. It uses LT3433, an automatic step up and step down switching regulator IC with 4V to 60V input voltage which can be useful in automotive electronics using various wide input voltage range.

According to the LT3433 datasheet, this Automatic Step-Up and Step-Down Conversion device is a 200kHz fixed frequency current mode switching regulator using a single inductor which can be applied in applications such as wall adapter powered systems and battery power voltage buffering.

Read completely about Step Up/Step Down DC to DC Converter Circuit Diagram using LT3433 here in pdf archive (source: linear.com)

Signals when an on-circuit battery is exhausted 5V to 12V operating voltage

A Battery-status Indicator circuit can be useful, mainly to monitor portable Test-gear instruments and similar devices. LED D1 flashes to attire the users attention, signaling that the circuit is running, so it will not be left on by mistake. The circuit generates about two LED flashes per second, but the mean current drawing will be about 200µA. Transistors Q1 and Q2 are wired as an uncommon complementary astable multivibrator: both are off 99% of the time, saturating only when the LED illuminates, thus contributing to keep very low current consumption. 

Circuit diagram :

Flashing-LED Battery-status Indicator Circuit Diagram

The circuit will work with battery supply voltages in the 5 - 12V range and the LED flashing can be stopped at the desired battery voltage (comprised in the 4.8 - 9V value) by adjusting Trimmer R4. This range can be modified by changing R3 and/or R4 value slightly.

When the battery voltage approaches the exhausting value, the LED flashing frequency will fall suddenly to alert the user. Obviously, when the battery voltage has fallen below this value, the LED will remain permanently off. To keep stable the exhausting voltage value, diode D1 was added to compensate Q1 Base-Emitter junction changes in temperature. The use of a Schottky-barrier device (e.g. BAT46, 1N5819 and the like) for D1 is mandatory: the circuit will not work if a common silicon diode like the 1N4148 is used in its place.

Parts :

R1,R7__________220R  1/4W Resistors
R2_____________120K  1/4W Resistor
R3_______________5K6 1/4W Resistor
R4_______________5K  1/2W Trimmer Cermet or Carbon
R5______________33K  1/4W Resistor
R6_____________680K  1/4W Resistor
R8_____________100K  1/4W Resistor
R9_____________180R  1/4W Resistor
C1,C2____________4µ7  25V Electrolytic Capacitors
D1____________BAT46  100V 150mA Schottky-barrier Diode
D2______________LED  Red 5mm.
Q1____________BC547   45V 100mA NPN Transistor
Q2____________BC557   45V 100mA PNP Transistor
B1_______________5V to 12V Battery supply
Notes :

• Mean current drawing of the circuit can be reduced further on by raising R1, R7 and R9 values. 

Easy Discrete Low Drop Regulator

This circuit was designed to ensure that an amplifier circuit containing a TDA1516Q would not exceed its maximum supply voltage when the load is small. This amplifier is used in a PC to increase the audio power somewhat. The PC power supply, however, created so much interference that an additional power supply was required.

Discrete Low-Drop Regulator Circuit Diagram

The power supply has its own power trans-former with a secondary voltage of 12 V AC. After rectification and filtering this results in a DC voltage of about 16 V. The regulator consists of a P-channel MOSFET SJ117, the gate of which is driven via a voltage divider connected to T2. The base of T2 is held at a constant voltage by LED D2, so that the volt-age across emitter resistor R2 is also constant and therefore carries a constant cur-rent. 

When the output voltage is higher than about 13.5 V, zener diode D1 will start to con-duct and supply part of the current through R2 — as a result the MOSFET will be turned on a little less. In this way there is a balance point, where the output voltage will be a little over 13.5 V (1.5 V across R2 plus the 12 V zener voltage). The regulator is capable of deliver-ing up to about 2 A — in any case it is a good idea to fit the MOSFET with a heatsink.

It is possible to add an optional potentiometer in series with the 12-V zener diode, which will allow a small amount of adjustment of the output voltage.The relay at the AC powerline input ensures that the power supply is only turned on when the PC is turned on. This relay is driven from a 4-way power supply connector from the PC.

Suzuki GSX1300 Hayabusa Charging System Circuit 99 – 00

The circuit of Suzuki GSX1300 Hayabusa Charging System composed of generator, regulator/rectifier unit and battery. The AC current generated from the generator is rectified by the rectifier and is turned into DC current, then it charges the battery. While the engine rpm is low and the generated voltage of generator is lower then the adjusted voltage of regulator, the regulator does not function. However, the generated current charges the battery directly at this time.

When the engine rpm becomes higher, the generated voltage of the generator also becomes higher and the voltage between the battery terminals becomes high accordingly. When it reaches the adjusted voltage of the integrated circuit and it is turned “ON”, a signal will be sent to the SCR (thyristor) gate probe and the SCR will be turned “ON”. Then the SCR becomes conductive in the direction from point A to point B. At this time the current generated from the generator gets through the SCR without charging the battery and returns to generator again.

Voltage Controlled Switch using 555 Timer descroption and circuit

Notes:
The old and omnipresent NE555 can be very good at something it was not meant for: driving relays or other loads up to 200 mA. The picture shows an example circuit: if the input level rises over 2/3 of the supply voltage - it will turn on the relay, and the relay will stay on until the level at the input drops below one third of the supply voltage.

If the relay and D1 were connected between pin 3 and ground, the relay would be activated when the input voltage drops below one third, and deactivated when the input voltage goes over two thirds of the supply voltage.

It is also a nice advantage that the input requires only about 1 uA, which is something bipolar transistors cant compete with. (This high impedance input must not be left open.) A large hysteresis makes the circuit immune to noise. The output (pin 3) can only be either high or low (voltage-wise), and it changes its state almost instantenously, regardless of the input signal shape.

The voltage drop across the NE555s output stage (at 35-100 mA) is 0.3-2.0 V, depending on the way the relay is connected and the exact current it draws. D1 is absolutely vital to the safety of the integrated circuit.Source :: http://www.zen22142.zen.co.uk/Circuits/Switching/vcs555.htm

Automatic TV Lighting Switch

The author is the happy owner of a television set with built-in Ambilight lighting in the living room. Unfortunately, the television set in  the bedroom lacks this feature. To make up for this, the author attached a small lamp to the wall to provide background lighting, This makes  watching television a good deal more enjoyable, but it ’s  not the ideal solution. Although the TV set can be  switched off with the remote  control, you still have to get out of bed to switch off the lamp.

Circuit diagram :

Automatic TV Lighting Switch Circuit Diagram

Consequently, the author devised this automatic lighting switch that switches the background light on and off along with the T V set. The entire circuit is fitted in series with the mains cable of the TV set, so there’s no need to tinker with the set. It works as follows: R1 senses  the current drawn by the TV  set. It has a maximum value  of 50 mA in standby mode,  rising  to around   500 m A  when  the  set  is  operating. The voltage across R1 is limited by D5 during negative  half- cycles  and  by  D1– D4  during positive half-cycles.  T he  voltage  across  these  four diodes charges capacitor C1 via D6 during positive  half-cycles. This voltage drives the internal LED of solid-state switch TRI1 via R2, which causes the internal triac to conduct and pass the mains voltage to the lamp.   Diode D7 is not absolutely necessary, but  it is recommended because the LED in the  solid-state switch is not especially robust  and cannot handle reverse polarisation. Fuse  F1 protects the solid-state switch against  overloads. T he  value  of  use d  here  (10 Ω)  for  resistor R1 works nicely with an 82-cm (32 inch)  LCD screen.

With smaller sets having lower  power consumption, the value of R1 can be  increased to 22 or 33 Ω, in which case you  should use a 3-watt type. Avoid using an  excessively high resistance, as otherwise TRI1 will switch on when the TV set is in standby mode.  Some TV sets have a half-wave rectifier in the  power supply, which places an unbalanced  load on the AC power outlet. If the set only  draws current on negative half-cycles, the cir-cuit won’t work properly. In countries with  reversible AC power plugs you can correct  the problem by simply reversing the plug. Compared with normal triacs, optically cou-pled solid-state relays have poor resistance  to high switch-on currents (inrush currents).

For this reason, you should be careful with  older-model TV sets with picture tubes (due  to demagnetisation circuits). If the relay fails,  it usually fails shorted, with the result that the TV background light remains on all the time. If you build this circuit on a piece of perf-board, you must remove all the copper next  to conductors and components carrying  mains voltage. Use PCB terminal blocks with a spacing of 7.5 mm. This way the separation between the connections on the solder  side will also be 3 mm. If you fit the entire  arrangement as a Class II device, all parts of  the circuit at mains potential must have a  separation of at least 6 mm from any metal  enclosure or electrically conductive exterior  parts that can be touched.

Description

Here is a simple and humble 2 Watts mini audio amplifier circuit suitable for small pocket radios and other portable audio gadgets.The circuit is based on Phillips Semiconductors IC TDA 7052.The amplifier can be run even from a 3V Mercury button cell.This makes it ideal for battery operated gadgets.

The IC TDA7052 is a mono output amplifier coming in a 8-lead DI package (DIP). The device is mainly designed for battery-operated portable audio circuits. The features of TDA 7052 include ,no external components needed,  no switch-on or switch-off click sounds , great overall stability ,very low power consumption(quiescent current 4mA) , low THD, no  heat sinks required and short-circuit proof.

The gain of TDA 7052 is fixed internally at 40 dB. . To compensate the reduction of output power due to low voltage supply  the TDA7052 uses the Bridge-Tied-Load principle (BTL) which can provide  an output  of around 1 to 2 W  Rms(THD = 10%) into an 8 Ohm load with a power supply of 6 V.

In the circuit the potentiometer can be used to control the volume. Capacitor C1 and C2 are meant for  filtering the supply voltage if a battery eliminator is used as supply source. For operations using a battery C1 and C2 are not necessary.

Mini Audio Amplifier Circuit Diagram with Parts List:

10 000x With One Transistor

For a collector follower with emitter resistor, you’ll often find that the gain per stage is no more than 10 to 50 times. The gain increases when the emitter resistor is omitted. Unfortunately, the distortion also increases. With a ubiquitous transistor such as the BC547B, the gain of the transistor is roughly equal to 40 times the collector current (Ic), provided the collector current is less than a few milliamps. This value is in theory equal to the expression q/KT, where q is the charge of the electron, K is Boltzmann’s constant and T is the temperature in Kelvin.

For simplicity, and assuming room temperature, we round this value to 40. For a single stage amplifier circuit with grounded emitter it holds that the gain Uout /Uin (for AC voltage) is in theory equal to SRc. As we observed before, the slope S is about 40Ic. From this follows that the gain is approximately equal to 40I cRc. What does this mean? In the first instance this leads to a very practical rule of thumb: that gain of a grounded emitter circuit amounts to 40·I c·Rc, which is equal to 40 times the voltage across the collector resistor.

If Ub is, for example, equal to 12 V and the collector is set to 5V, then we know, irrespective of the values of the resistors that the gain will be about 40R(12–5) = 280. Notable is the fact that in this way the gain can be very high in theory, by selecting a high power supply voltage. Such a voltage could be obtained from an isolating transformer from the mains. An isolating transformer can be made by connecting the secondaries of two transformers together, which results in a galvanically isolated mains voltage.

Circuit diagram:

That means, that with a mains voltage of 240 Veff there will be about 340 V DC after rectification and filtering. If in the amplifier circuit the power supply voltage is now 340 V and the collector voltage is 2 V, then the gain is in theory equal to 40 x (340–2). This is more than 13,500 times! However, there are a few drawbacks in practice. This is related to the output characteristic of the transistor. In practice, it turns out that the transistor does actually have an output resistor between collector and emitter.

This output resistance exists as a transistor parameter and is called ‘hoe’. In normal designs this parameter is of no consequence because it has no noticeable effect if the collector resistor is not large. When powering the amplifier from 340 V and setting the collector current to 1 mA, the collector resistor will have a value of 338 k. Whether the ‘hoe’-parameter has any influence depends in the type of transistor. We also note that with such high gains, the base-collector capacitance in particular will start to play a role.

As a consequence the input frequency may not be too high. For a higher bandwidth we will have to use a transistor with small Cbc, such as a BF494 or perhaps even an SHF transistor such as a BFR91A. We will have to adjust the value of the base resistor to the new hfe. The author has carried out measurements with a BC547B at a power supply voltage of 30 V. A value of 2 V was chosen for the collector voltage. Measurements confirm the rule of thumb. The gain was more than 1,000 times and the effects of ‘hoe’ and the base-collector capacitance were not noticeable because of the now much smaller collector resistor.