Sunday, August 31, 2014

16W Audio Amplifier with LM383 schematic diagram

Here the 16 watt power audio amplifier schema powered by dual IC LM383. The single LM383 will amplify the input about 7-8 watt, dual IC should be gain up to 16 watt. You can use wide voltage range 5V - 20V to supply the power IC.
16W
Component list:

U1, U2____________ LM383 power IC
R1, R3____________ 220 Ohm resistor
R2, R4____________ 2.2 Ohm resistor
R5________________ 1 MegaOhm resistor
R6________________ 100k potentiometer
C1, C7____________ 10uf electrolytic capacitor
C2, C5____________ 470uf electrolytic capacitor
C3, C4, C6________ 0.2uf ceramic capacitor
SPKR1_____________ 4 to 8 ohm speaker (up to 8 inches diameter)
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TDA1015 Audio Amplifier 1x4W

TDA1015general description:


The TDA1015 is a monolithic integrated audio amplifier circuit in a 9-lead single in-line (SIL) plastic package. The device is especially designed for portable radio and recorder applications and delivers up to 4 W in a 4Ω load impedance. The very low applicable supply voltage of 3,6 V permits 6 V spplications.

TDA1015 features:


  • single in-line (SIL) construction for easy mounting
  • separated preamplifier and power amplifier
  • high output power
  • thermal protection
  • high input impedance
  • low current drain
  • limited noise behaviour at radio frequencies

TDA1015 reference data:


  • Supply voltage range VP 3,6 to 18 V
  • Peak output current IOM max. 2,5 A
  • Output power at dtot= 10%
  • VP = 12 V; RL = 4 Ω Po typ. 4,2 W
  • VP = 9 V; RL = 4 Ω Po typ. 2,3 W
  • VP = 6 V; RL = 4 Ω Po typ. 1,0 W
  • Total harmonic distortion at Po = 1 W; RL = 4 Ω dtot typ. 0,3 %
  • Input impedance preamplifier (pin 8) |Zi | > 100 kΩ power amplifier (pin 6) |Zi| typ. 20 kΩ
  • Total quiescent current Itot typ. 14 mA
  • Operating ambient temperature Tamb −25 to + 150 °C
  • Storage temperature Tstg −55 to + 150 °C

TDA1015 circuit diagram:


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Hard Disk Selector

In the last few years, the available range of operating systems for PCs has increased dramatically. Various free (!) operating systems have been added to the list, such as BeOS, OpenBSD and Linux. These systems are also available in different colours and flavours (versions and distributions). Windows is also no longer simply Windows, because there are now several different versions (Windows 95, 98, ME, NT, XP, Vista and 7). Computer users thus have a large variety of options with regard to the operating system to be used. One problem is that not all hardware works equally well under the various operating systems, and with regard to software, compatibility is far from being universal. In other words, it’s difficult to make a good choice.


Switching from one operating system to another - that’s a risky business, isn’t it? Although this may be a bit of an exaggeration, the safest approach is still to install two different operating systems on the same PC, so you can always easily use the ‘old’ operating system if the new one fails to meet your needs (or suit your taste). A software solution is often used for such a ‘dual system’. A program called a ‘boot manager’ can be used to allow the user to choose, during the start-up process, which hard disk will be used for starting up the computer. Unfortunately, this does not always work flawlessly, and in most cases this boot manager is replaced by the standard boot loader of the operating system when a new operating system is installed.

In many cases, the only remedy is to reinstall the software. The solution presented here does not suffer from this problem. It is a hardware solution that causes the primary and secondary hard disk drives to ‘swap places’ when the computer is started up, if so desired. From the perspective of the computer (and the software running on the computer), it appears as though these two hard disks have actually changed places. This trick is made possible by a feature of the IDE specification called ‘CableSelect’. Every IDE hard disk can be configured to use either Master/Slave or CableSelect. In the latter case, a signal on the IDE cable tells the hard disk whether it is to act as the master or slave device. For this reason, in every IDE cable one lead is interrupted between the connectors for the two disk drives, or the relevant pin is omitted from the connector.


This causes a low level to be present on the CS pin of one of the drives and a high level to be present on the CS pin of the other one (at the far end of the cable). The schema shown here is connected to the IDE bus of the motherboard via connector K1. Most of the signals are fed directly from K1 to the other connectors (K2 and K3). An IDE hard disk is connected to K2, and a second one is connected to K3. When the computer is switched on or reset, a pulse will appear on the RESET line of the IDE interface. This pulse clocks flip-flop IC1a, and depending on the state of switch S1, the Q output will go either high or low. The state on the Q output is naturally always the opposite of that on the Q output. If we assume that the switch is closed during start-up, a low level will be present on D input of IC1a, so the Q output will be low following the reset pulse.


This low level on the Q output will cause transistor T1 to conduct. The current flowing through T1 will cause LED D1 to light up and transistor T2 to conduct. The hard disk attached to connector K2 will thus see a low level on its CS pin, which will cause it to act as the master drive and thus appear to the computer as the C: drive. A high level will appear on the Q output following the reset pulse. This will prevent T3 and T4 from conducting, with the consequence that LED D2 will be extinguished and the hard disk attached to connector K3 will see a high level on its CS pin. For this disk, this indicates that it is to act as a slave drive (D: drive).


If S1 is open when the reset pulse occurs, the above situation is of course reversed, and the hard disk attached to connector K2 will act as the D: drive, while the hard disk attached to connector K3 will act as the C: drive. Flip-flop IC1a is included here to prevent the hard disks from swapping roles during use. This could have disastrous consequences for the data on the hard disks, and it would most likely cause the computer to crash. This means that you do not have to worry about affecting the operation of the computer if you change the switch setting while the computer is running. The state of the flip-flop, and thus the configuration of the hard disks, can only be changed during a reset.

The schema is powered from a power connector for a 3.5-inch drive. This advantage of using this connector is that it easily fits onto a standard 4-way header. However, you must observe the correct polarity when attaching the connector. The red lead must be connected to pin 1. Constructing the hard disk selector is easy if the illustrated printed schema board is used. You will need three IDE cables to connect the schema. The best idea is to use short cables with only two connectors, with all pins connected 1:1 (no interruption in the CS line). The IDE connector on the motherboard is connected to K1 using one cable. A cable then runs from K2 to first hard disk, and another cable runs from K3 to the second hard disk. This means that it is not possible to connect more than two hard disks to this schema. You must also ensure that the jumpers of both disk drives are configured for CableSelect. To find out how to do this, refer to the user manual(s) for the drives.
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25W Power Amplifier based IC LM1875

Short schema protection, 94dB supply rejection ratio, thermal protection, S/N ratio in excess of 100dB, Open loop gain typically 90dB and 70mA quiescent current, LM1875 is great enough to give you good audio performmance. This power IC will amplify the audio signal up to 30W output power.


25W

Component part list

R1 _____________ 1K
R2 _____________ 1M
R3 _____________ 22K
R4 _____________ 10K
R5 _____________ 180K
R6 _____________ 1R

IC1 ____________ LM1875
C1 _____________ 1uF 50V
C2,6 ___________ 100nF
C3 _____________ 22uF 63V
C4 _____________ 0.22uF
C7,5 ___________ 220uF 50V

Miscellaneous:
Fuse holder & cover
2 amp fuses


Visit this 25W Power Amplifier page for detail explanation
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SP Semi Automatic Paintbrush

Got a replacement InkShield and progressing to build an Open hardware project? Then why not strive creating the Semi-Automatic Paintbrush. browse on to grasp a lot of concerning this.



Any work of art are often copied using this and therefore the elements that are needed to form this is often listed below:
IR camera
InkShield
Ink cartridge
IR LED.

The software thats run on a desktop for this purpose is understood as paintbrush.py. The software plays the role of mapping the camera focus with the co-ordinate system of the canvas. Four LEDs are placed at every corner of the canvas and therefore the mapping is calibrated by hitting a key when needed.

The region of the image is captured by tracking the motion of the LEDs. the mandatory commands are send to an Arduino with the InkShield by means that of a script written for this purpose. The script tells the arduino that nozzle to fireplace and additionally the grey level that must be achieved by the firing nozzle. so as to avoid flooding, the painted areas are tracked.

Thats all its. The paintbrush is complete. this is often a lot of of a fun-based project and may be tired some spare time using the elements mentioned earlier. the desired script is out there on github. The InkShield library employed by the
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Saturday, August 30, 2014

Simple Fm Transmitter Wiring diagram Schematics



Most of you guys send  emails to Free schema diagrams 4u asking Fm transmitters so today we are going to give you a simple transmitter schema diagram.The special thing of this schema is we can use this schema with 9V power supply and We have used a common transistor 2N3904 for this schema.You can send signals up to 100-150M.you can use this as a spy schema.




Note: 

 # Build this schema on a pcb 
 # Dont supply over 9V 
# This is only for educational purpose, We dont get any responsibility of misusing this schema 
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USB Powered Audio Power Amplifier Wiring diagram Schematic

This USB Powered Audio Power Amplifier Circuit Diagram of multimedia speakers for PCs has single-chip-based design, low-voltage power supply, compatibility with USB power, easy heat-sinking, low cost, high flexibility and wide temperature tolerance. At the heart of the schema is IC TDA2822M. This IC is, in fact, mono-lithic type in 8-lead mini DIP package. It is intended for use as a dual audio power amplifier in battery-powered sound players. Specifications of TDA2822M are low quiescent current, low crossover distortion, supply voltage down to 1.8 volts and minimum output power of around 450 mW/channel with 4-ohm loudspeaker at 5V DC supply input. 

An ideal power amplifier can be simply defined as a schema that can deliver audio power into external loads without generating significant signal distortion and without consuming excessive quiescent current. This schema is powered by 5V DC supply available from the USB port of the PC. When power switch S1 is flipped to ‘on’ position, 5V power supply is extended to the schema and power-indicator red LED1 lights up instantly. Resistor R1 is a current surge limiter and capacitors C1 and C4 act as buffers. Working of the schema is simple. Audio signals from the PC audio socket/headphone socket are fed to the amplifier schema through components R2 and C2 (left channel), and R3 and C3 (right channel).

Circuit diagram:
USB
USB Powered Audio Power Amplifier Circuit Diagram

Potmeter VR1 works as the volume controller for left (L) channel and potmeter VR2 works for right (R) channel. Pin 7 of TDA2822M receives the left-channel sound signals and pin 6 receives the right-channel signals through VR1 and VR2, respectively. Ampl i f ied signals for driving the left and right loudspeakers are available at pins 1 and 3 of IC1, respectively. Components R5 and C8, and R6 and C10 form the traditional zobel network. Assemble the schema on a medium-size, general-purpose PCB and enclose in a suitable cabinet. It is advisable to use a socket for IC TDA2822M. The external connections should be made using suitably screened wires for better result.
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Traffic Lights Circuit

The circuit of traffic lights in my opinion is a series of easy-hard-easy to make. 



Traffic

Where we are required to be able to condition the flame of three lamps by following the existing traffic regulations. If we use computer programming as a regulator of the third condition of the lights probably we will not spend too much time to make it. As an example with microcontroller programming or programming-based computer applications such as Visual Basic, Delphi and many others. But if you use a common electronic circuit components used may be somewhat time consuming to get the results you are fully in accordance with the conditions of traffic lights that use the streets.

Well ... if youre looking for examples of a series of simple traffic light above the range can I recommend to you. The working principle of a series of traffic light above is very easy to understand. The series of above use the output from IC up / down counter 74 190 as the producer output tercacah and then conditioned using logic gates so that the logic in accordance with the logic of the actual traffic light. Actually you can also use the IC counter ups as pencacahnya. Red lights are represented by the LED D1, D2 and yellow by green led by led D3.

LIST OF COMPONENTS:
Resistors: R1 (1 Kohm), R2, R3 and R4 (220 ohms) and VR1 (Potensio 10 K / 15 K)
Capacitors: C1 (100 UF)
Led: D1 (red), D2 (yellow) and D3 (green).
Integrated Circuit: IC1 (NE 555), IC2 (74LS190) and IC3 (74LS02)

HOW TO WORK AND ANALYSIS OF CIRCUIT LIGHT TRAFFIC:
To generate the signal used peggerak counter circuit astable circuit IC555.
R1, C1 and VR1 is a combination astable as a determinant of the speed of the clock signal to be inserted to the input counter and in the end will determine the length of time the flame of their lamps. The greater the value of the three clock cycles will stay longer and vice versa.
To obtain a combination of LEDs required only 2 bits output from the counter circuit.
Bit-3 from the output to the counter only be used as reset the enumeration.
The lamp was first lit the light yellow color, due to connect with the output Q1 of counter IC. Then followed by a red lamp that is connected to the output Q2. Then both (yellow and red) light simultaneously. The last green light will turn on its own.
The series of bit counter counts up with the sequence:
- 0 1 (light yellow light)
- 1 0 (red light)
- 1 1 (light yellow and red lights)
- 0 0 (light turned green, according to the nature of the gate NOR)
Examples of traffic light sequence apply only to one lane for traffic light circuit that uses more than one line then you can use the same circuit device and use a combination of gates as a liaison between the conditions of each lane. This means you should make a longer red light is illuminated on each other point for point which it operates. These conditions can be achieved by utilizing a combination of logic gates in a chain.
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Simple 12V to 120V Inverter Wiring diagram Schematic

This is the Simple 12V to 120V Inverter Circuit Diagram. This Simple 12V to 120V Inverter Circuit Diagram should solve that problem. It takes 12 VDC and steps it up to 120 VAC. The wattage depends on which tansistors you use for Q1 and Q2, as well as how "big" a transformer you use for T1. The inverter can be constructed to supply anywhere from 1 to 1000 (1 KW) watts.

Simple 12V to 120V Inverter Circuit Diagram

Simple

Parts List 
  
Substitutions - Total Qty.- Description
C1, C2             2                 68 uf, 25 V Tantalum Capacitor   
R1, R2              2                 10 Ohm, 5 Watt Resistor   
R3, R4              2                180 Ohm, 1 Watt Resistor   
D1, D2              2                HEP 154 Silicon Diode   
Q1, Q2             2                2N3055 NPN Transistor (see "Notes")   
T1                      1               24V, Center Tapped Transformer (see "Notes")   
MISC                1               Wire, Case, Receptical (For Output)
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Friday, August 29, 2014

Schematic Power Amplifier with IC AN7114 or AN7115

This Circuit must use the IC AN7114 or you can use the IC AN7115 . Minimum voltage for this IC is 6 Volt and maximum voltage is 11 . You can supply this Circuit with 12 Volt if  you use IC AN7115 because its maximum voltage 13 volt. Output Power 1 watt with Impedance 4 ohm . 

 See the Schematic (figure 2.0) and package IC (figure 1.0) :


Figure 1.0
Figure 2.0
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Electronic Audio Controlled Switch Wiring diagram Schematic

This is a simple Electronic Audio Controlled Switch Circuit Diagram. This audio-controlled switch combines a pair of 741 op amps, two 2N2222 general-purpose transistors, a hexFET, and a few support components to a schema that can be used to turn on a tape recorder, a transmitter, or just about anything that uses sound.

Electronic Audio Controlled Switch Circuit Diagram


Electronic

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Simple Pulse Train Wiring diagram Schematic

This is a Simple Pulse Train Game Circuit Diagram. This schema has a rate multiplier using a 4093 Schmitt trigger as an oscillator, driving a 4017 decade counter. When a pulse present at the input (to C2) 4017 is reset, output zero goes high, and outputs 1 to 9 go low. The oscillator (4093) starts running and the 4017 counts the pulses until the 4017 output (1 to 9) connected to pin 1 and 2 of the 4093 goes high. The oscillator is inhibited and the output remains high until the next input pulse.

Simple Pulse Train Circuit Diagram


Simple

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TDA8559T Low voltage stereo headphone amplifier



General description for TDA8559T:

The TDA8559T is a stereo amplifier that operates over a wide supply voltage range from 1.9 V to 30 V and consumes a very low quiescent current. This makes it suitable for battery fed applications (2 × 1.5 V cells). Because of an internal voltage buffer, this device can be used with or without a capacitor connected in series with the load. It can be applied as a headphone amplifier, but also as a mono amplifier with a small speaker (25 Ω), or as a line driver in mains applications.

Features for TDA8559T:

  • Operating voltage from 1.9 V to 30 V
  • Very low quiescent current
  • Low distortion
  • Few external components
  • Differential inputs
  • Usable as a mono amplifier in Bridge-Tied Load (BTL) or stereo Single-Ended (SE)
  • Single-ended mode without loudspeaker capacitor
  • Mute and Standby mode
  • Short-circuit proof to ground, to supply voltage (< 10 V) and across load
  • No switch on or switch off clicks
  • SD protected on all pins

Applications for TDA8559T:

  • Portable telephones
  • MP3 players
  • Portable audio
  • Mains fed equipment
Circuit diagram for TDA8559T:

PCB layout for TDA8559T:


Datasheet for TDA8559T: Download


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Simple Bidirectional Compound Op Amp Wiring diagram Schematic

This is a Simple Bidirectional Compound Op Amp Circuit Diagram. Using two transistors (Ql and Q2), a bidirectional op amp can source or sink up to 50 mA. Dl and D2 provide b ias for Ql to eliminate `dead-zone` effects.

Simple Bidirectional Compound Op Amp Circuit Diagram


Simple

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Thursday, August 28, 2014

Offline Converter Wiring diagram Schematic

This nonisolated, unregulated, minimum component converter fills the void between low-power zener regulation and the higher power use of a 60-Hz input transformer. It is intended for use where)`er a nonisolated supply can be used safely. 

The schema operates~by conducting only during the low-voltage portion of the rectified sine wave. Rl and D2 charge Cl to approximately 20 V, which is maintained by Ql. This voltage is applied to the gate of Q2, turning it on. When the rectified output voltage exceeds the zener voltage ofD4, Ql turns on, shunting the gate of Q2 to ground, turning it off.

Offline Converter Circuit Diagram


Offline

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Open Loop Close Loop Speed control for induction motors


Open Loop Speed control for induction motors.




 In the above block diagram the Open Loop Speed control for induction motors is shown.
The system consists of theRectifier, Filter, Three phase variable Frequency Inverter and induction motor.
The controlled rectifier converted the tree phase supply to a DC, the out put of the rectifier is a pulsing DC, there fore it is passes through the Filter, after the filter the DC voltage is feed to the variable frequency inverter ckt and the it supply to the induction.
There is no feed back in this system for the control purpose there it is called Open Loop control System.

 Closed Loop Speed control for induction motors.

           
In the above block diagram the Close Loop Speed control for induction motors is shown.
The system consist of theRectifier, Filter, Three phase variable Frequency Inverter, Feed back system and induction motor.
The main operation of the Closed Loop Speed control for induction motor is same as of the Open Loop system, In this system simply a feed back system is introduce to control for control purpose.


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Simple On off Inverters Wiring diagram Schematic

This is a Simple On-off Inverters switch Circuit Diagram. Each time the switch closes, the voltage on Cl causes inverter A to change state, with positive feedback from inverter B. Resistor Rl delays the charging and discharging of Cl, making the schema virtually immune to contact bounce. The schema works with either CMOS or TTL gates. The values of R1 and C1 are not critical and can be increased for greater contact bounce protection, if needed. Recommended ranges are 10 K to 1 MO for Rl, and 0.01 to 1.0 p.F for Cl.

Simple On-off Inverters Circuit Diagram

Simple

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LM3914 battery level indicator

LM3914
Battery level indicator circuit is a circuit that is used to measure the battery voltage / battery. The main components of the battery level indicator circuit is an LM3914 IC. LM 3914 on Circuit battery level indicator is a monolithic IC that detects an analog voltage. And drive the 10 LEDs that produce a linear analog display on a given input voltage.

IC LM3914 is easy to get in the market and not expensive. IC LM3914 battery level indicator on the circuit is often encountered in a series of peak indicator audio signals in analog audio equipment. Battery level indicator circuit consists of IC LM3914, 10 pieces of LED, and a few resistors. The scheme of  battery level indicator can be seen below.

LM3914 battery level indicator

In the circuit of the battery level indicator on the supply circuit voltage taken from the battery / batteries through a switch. Didesaimn this circuit will only display the battery level when the switch is pressed. This is intended to save the battery voltage itself.
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Guitar treble boost

Description

Ql is connected as an emitter follower in order to present a high input impedance to the guitar. C2, being a relatively low capacitance, cuts out most of the bass, and C3 with RV1 acts as a simple tone control to cut the treble, and hence the amount of treble boost can be altered.Q2 is a simple preamp to recover signal losses in C2, C3, and RV1.

Circuit Diagram


Guitar treble boost   

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Wednesday, August 27, 2014

Mains Supply Failure Alarm Wiring diagram Schematic

Whenever AC mains supply fails, this schema alerts you by sounding an alarm. It also provides a backup light to help you find your way to the torch or the generator key in the dark. The schema is powered directly by a 9V PP3/6F22 compact battery. Pressing of switch S1 provides the 9V power supply to the schema. A red LED (LED2), in conjunction with zener diode ZD1 (6V), is used to indicate the battery power level.

Resistor R9 limits the operating current (and hence the brightness) of LED2. When the battery voltage is 9V, LED2 glows with full intensity. As the battery voltage goes below 8V, the intensity of LED2 decreases and it glows very dimly. LED2 goes off when the battery voltage goes below 7.5V. Initially, in standby state, both the LEDs are off and the buzzer does not sound. The 230V AC mains is directly fed to mains-voltage detection optocoupler IC MCT2E (IC1) via resistors R1, R2 and R3, bridge rectifier BR1 and capacitor C1.

Illumination of the LED inside optocoupler IC1 activates its internal phototransistor and clock input pin 12 of IC2 (connected to 9V via N/C contact of relay RL1) is pulled low. Note that only one monostable of dual-monostable multivibrator IC CD4538 (IC2) is used here. When mains goes off, IC2 is triggered after a short duration determined by components C1, R4 and C3. Output pin 10 of IC2 goes high to forward bias relay driver transistor T1 via resistor R7.

Circuit diagram:

Mains
Mains Supply Failure Alarm Circuit Diagram

Relay RL1 energises to activate the piezo buzzer via its N/O contact for the time-out period of the monostable multivibrator (approximately 17 minutes). At the same time, the N/C contact removes the positive supply to resistor R4. The time-out period of the monostable multivibrator is determined by R5 and C2. Simultaneously, output pin 9 of IC2 goes low and pnp transistor T2 gets forward biased to light up the white LED (LED1).

Light provided by this back-up LED is sufficient to search the torch or generator key. During the mono time-out period, the schema can be switched off by opening switch S1. The ‘on’ period of the monostable multivibrator may be changed by changing the value of resistor R5 or capacitor C2. If mains doesn’t resume when the ‘on’ period of the monostable lapses, the timer is retriggered after a short delay determined by resistor R4 and C3.
Source: EFY Mag
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LM390 power amplifier schematic

Circuit schematic above is / include power amplifiers that have low power output. 1 Watt output power is only based on the IC , and ic used LM390 , manufactered by NS and ic packaged in DIP-14. For output impedance have 4 OHm. Requires a minimum voltage 4 Volt and Maximum voltage is only 9Volt.
Part List :

Resistor
R1________33K
R2________510R
R3________510R
R4________2.7R

Capacitor
C1________100uF 16V
C2________100uF 16V
C3________10uF   16V
C4________220uF 35V
C5________10uF   16V
C6________100n

IC
IC1_______LM390 

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Cranial Electrotherapy Stimulator Wiring diagram Schematic

Owing to the recent launching in Europe of Cranial Electrotherapy Stimulation (CES) portable sets, we have been "Electronically Stimulated" in designing a similar schema for the sake of hobbyists. CES is the most popular technique for electrically boosting brain power, and has long been prescribed by doctors, mainly in the USA, for therapeutic reasons, including the treatment of anxiety, depression, insomnia, and chemical dependency. CES units generate an adjustable current (80 to 600 microAmperes) that flows through clips placed on the earlobes. 

The waveform of this device is a 400 milliseconds positive pulse followed by a negative one of the same duration, then a pause of 1.2 seconds. The main frequency is 0.5 Hz, i.e. a double pulse every 2 seconds. Some people report that this kind of minute specialized electrical impulses contributes to achieve a relaxed state that leaves the mind alert. Obviously we cant claim or prove any therapeutic effectiveness for this device, but if you are interested in trying it, the schema is so cheap and so simple to build that an attempt can be made with quite no harm.

Circuit diagram:
cranial-electrotherapy-stimulator-schema
Parts:
R1___________1M5 1/4W Resistor
R2___________15K 1/4W Resistor
R3___________100K Linear Potentiometer
R4___________2K2 1/4W Resistor
C1___________330nF 63V Polyester Capacitor
C2___________100µF 25V Electrolytic Capacitor
D1___________3mm. Red LED
IC1___________7555 or TS555CN CMos Timer IC
IC2___________4017 Decade counter with 10 decoded outputs IC
SW1__________SPST Slider Switch
B1____________9V PP3 Battery Clip for PP3 Battery
Two Earclips with wires (see notes)

Circuit operation:

IC1 forms a narrow pulse, 2.5Hz oscillator feeding IC2. This chip generates the various timings for the output pulses. Output is taken at pins 2 & 3 to easily obtain negative going pulses also. Current output is limited to 600µA by R2 and can be regulated from 80 to 600µA by means of R3. The LED flashes every 2 seconds signaling proper operation and can also be used for setting purposes. It can be omitted together with R4, greatly increasing battery life.

Notes:
  • In order to obtain a more precise frequency setting take R1=1M2 and add a 500K trimmer in series with it.
  • In this case use a frequency meter to read 2.5Hz at pin 3 of IC1, or an oscilloscope to read 400msec pulses at pins 2, 3 or 10, adjusting the added trimmer.
  • A simpler setting can be made adjusting the trimmer to count exactly a LED flash every 2 seconds.
  • Earclips can be made with little plastic clips and cementing the end of the wire in a position suited to make good contact with earlobes.
  • Ultra-simple earclips can be made using a thin copper foil with rounded corners 4 cm. long and 1.5 cm. wide, soldering the wire end in the center, and then folding the foil in two parts holding the earlobes.
  • To ensure a better current transfer, this kind of devices usually has felt pads moistened with a conducting solution interposed between clips and skin.
  • Commercial sets have frequently a built-in timer. Timing sessions last usually 20 minutes to 1 hour. For this purpose you can use the Timed Beeper the Bedside Lamp Timer or the Jogging Timer diagram available on this website, adjusting the timing components in order to suit your needs.

Streampowers
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Boster 15 watt rd 15 no tune

15 rd booster requires only 0.5 watts of input capable of out 15 watts, the voltage of 13.8 volts it needs. in this series are made to work freq 87-108 mhz fm broadcast. but did not rule to be modified in other freq. schematic and pcb layout to please download here

 

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LM380 mini Audio Amplifier

This be mini size power amplifier 2 watt OTL that use IC LM380. Be base readymade circuit for side sound work and the communication. Which use outside equipment adds least. The C6 can choose get many the value since 47uF to at 470uF which , have a voice good bass. The C3 use for decrease tall frequency or noise. It be valuable stay between 0.0047uF sections arrive at 0.047uF. And use to The 12V power supply (8V to 12V) from , car battery or the other.The Pin 3,4,5,10,11 legs and 12 soldered directly with copper side of PCB. Which use replace Heat sink The detail is other , see in the circuit.

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Tuesday, August 26, 2014

12 Volt Battery Guardian

Dont get caught with a flat battery; this easy-to-build schema can cut off the power to a 12V fridge or car stereo system if the battery voltages drops below critical level. Electric fridges in vans and 4WDs are a great idea but if you are not careful, they can severely discharge the battery and leave you stranded. Maybe the battery will end up with severe damage as well. The same problem applies if you have a big stereo system and you like to play it without the motor running.


Main features:
  • Cuts power to load (eg, fridge) when battery voltage drops below a preset level.
  • 10A rating.
  • Low power drain.
  • Chirping sound during cut-out.
  • Flashing LED indication during cut-out.
  • Automatically reconnects power when battery recharged.
Operation on 12V is fine when the motor is running and battery charge is maintained but if the fridge is allowed to run for too long when the motor is stopped, it can flatten the battery in a relatively short time. This is where the Battery Guardian comes into play. It monitors the battery voltage and disconnects power to the fridge before the battery becomes too flat to allow the engine to be started again.

Parts layout:



PCB layout:


Circuit diagram:




Source: Silicon Chip 6 May 2002
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Loudspeaker Protector Monitors Current Wiring diagram Schematic

This schema uses a 0.1O 1W resistor connected in series with the output of a power amplifier. When the amplifier is delivering 100W into an 8O load, the resistor will be dissipating 1.25W. The resulting temperature rise is sensed by a thermistor which is thermally bonded to the resistor. The thermistor is connected in series with a resistor string which is monitored by the non-inverting (+) inputs of four comparators in an LM339 quad comparator. All of the comparator inverting inputs are connected to an adjustable threshold voltage provided by trimpot VR1. As the thermistor heats up, its resistance increases, raising the voltage along the resistor ladder.


loudspeaker-protector-schema-diagram-monitors-current Loudspeaker Protector Circuit Diagram

When the voltage on the non-inverting input of each comparator exceeds the voltage at its inverting input, the output switches high and illuminates the relevant LED. NOR gate latches are connected to the outputs of the third and fourth comparators. When the third comparator switches high, the first latch is set, turning on Q1 and relay 1. This switches in an attenuation network (resistors RA & RB) to reduce the power level. However, if the power level is still excessive, comparator 4 will switch, setting its latch and turning on Q2 and relay 2.

This disconnects the loudspeaker load. The thermistor then needs to cool down before normal operation will be restored. The values of R1-R4 depend on the thermistor used. For example, if a thermistor with a resistance of 1.5kO at 25°C is used, then R1 could be around 1.5kO and R2, R3 and R4 would each be 100O (depending the temperature coefficient of the thermistor). The setup procedure involves connecting a sinewave oscillator to the input of the power amplifier and using a dummy load for the output. Set the power level desired and adjust trimpot VR1 to light LED1. Then increase the power to check that the other LEDs light at satisfactory levels.


Source by : Streampowers
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Digital Stop Watch


A digital stop watch built around timer IC LM555 and 4-digit counter IC MM74C926 with multiplexed 7-segment LED display.MM74C926 consists of a 4-digit counter, an internal output latch, npn output sourcing drivers for common cathode,






7-segment display and an internal multiplexing schemary with four multiplexing outputs.The counter advances on negative edge of the clock. The clock is generated by timer IC LM555.The schema works off a 5V power supply. It can be easily assembled on a general-purpose PCB. Enclose the schema in a metal box
with provisions for four 7-segment displays, rotary switch S1, start/stop switch S2 and reset switch S3





Testing

First, reset the schema by pressing S3 so that the display shows ‘0000.’ Now open switch S2 for the stop watch to start counting the time. If you want to stop the clock, close S2. Rotary switch S1 is used to select the different time periods at the output of the astable multivibrator (IC1).

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12 Volt DC Power Suplly Adaptor

This series of images you can apply to make an adapter or power suplly with the output voltage (V DC output 12V). Power supply in the only protected by a capacitor as a safety if the power supply is connected to the load on the circuit.


So I recommend using 35V capacitor with a minimum specification. The security of power supply to power the more we can menggunakkan transistor TIP, but I have not discussed it. To the diode bridge can be compiled from the 4 then you solder the diode bridge rectifier into one or you can buy a bridge rectifier so that the comb-shaped (sideways) or the box. At least I would suggest using a diode bridge 1 Ampere, in a series of adapters, the bigger the better course of ampere diode current in the circuit. Diodes like toll roads, and current as a car passing by. The larger and the width of the existing highway, the faster the flow of runs and through the circuit.

For the circuit power supply 5 V, you can change the volt regulator on the type 7805 and 7905. This application applies equally in this series. For variations such as fuse or circuit switch on / off you can try it yourself.
Transformer 18 V + - 1 A minimum CT
Minimum of 35 V + Capacitor
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3 Band Tone Control with LF351

3 Band Tone Control circuit uses an op-amp as an amplifier end. Tone Control circuit is a regulator of tone bass, midrange and treble or 3 band called because it can set the three tones. Filter circuit is applied to the series of "Tone Control 3 band" This type baxandal like the title of this article. 

Results filtering regulator tone or tone control baxandal type is good, because there is no signal level is wasted directly into the ground. Range frequency tones generated from Tone Control 3 band was determined by the configuration of the R and C of the filter section baxandal. As an amplifier on Tone Control The set of three band use traditional IC LF351 has slewrate high and high input impedance. For more details, series 3 Band Tone Control as follows.

Figure Series 3 Band Tone Control

3

3 Band Tone Control circuit above using LF351 Op-Amp is used to strengthen the signal after filtering by the filter process baxandal. Level tone Bass, Midrange and Treble settings are determined by potensio R1, R2 and R3. Frequency filter in the circuit above baxandal to 50 Hz bass tone, tone Midrange 1 KHz and 10 KHz for Treble tone.
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Monday, August 25, 2014

20W Bridge Car Amplifier based TDA7240A

The following schema diagram is a bridge amplifier which specially designed for car audio system. The schema is very simple with few external components supporting the power IC TDA7240A. This schema will produce a maximum power output of 20W

Schematic Diagram:

20W

PCB Layout:

20W


The schema diagram and PCB layout come from the IC TDA7240A datasheet. Download TDA7240A datasheet for schema reference.

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TDA1010A 2 x 6W audio power amplifier

Description:

     The TDA1010A is a monolithic integrated class-B audio amplifier circuit in a 9-lead single in-line (SIL) plastic package. The device is primarily developed as a 6 W car radio amplifier for use with 4Ωand 2Ωload impedances. The wide supply voltage range and the flexibility of the IC make it an attractive proposition for record players and tape recorders with output powers up to 10 W.

Special features:

  • single in-line (SIL) construction for easy mounting 
  • separated preamplifier and power amplifier 
  • high output power 
  • low-cost external components 
  • good ripple rejection 
  • thermal protection 

Reference:

  • Supply voltage range Vp...........................6 to 24 V 
  • Repetitive peak output current IORM...........max. 3 A 
  • Operating ambient temperature Tamb ........−25 to + 150 °C 
  • Storage temperature Tstg ........................−55 to + 150 °C 

Circuit diagram:
Tda1010A Circuit Diagram

Tda1010A layout

Tda1010A pcb
    

Datasheet for TDA1010A: Download
Where you can buy: Aliexpress
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24V DC Powered Beeper with 4 Separate Inputs

24v DC is a very popular voltage used in industrial settings. This hobby schema below was designed to accept four different 24v DC alarm input signals, which are then used to drive a single low power beeper. The beeper is a magnetic type with its own oscillator/driver. The four diodes form an “OR” gate so any one of the four inputs will cause the beeper to make noise. A CMOS version of the popular 555 timer is used to strobe the beeper on and off at about 1Hz.


24V


Copyright: Discover Circuits
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