Wiring Material: October 2014

Friday, October 17, 2014

2N3055 and LM723 Power Supply 13 8Volt 10Amp circuit

My Friend want circuit power supply for VR.
I Find Website many, See to this Web http://www.rason.org
Good Site circuit.
This is circuit Power Supply 13.8 Volt 10 Amp by LM723 .
Detail ::

This circuit uses the LM723 IC which gives us excellent voltage regulation. The circuit uses 3 pass transistors which must be heat sinked. Resistor R9 allows the fine tuning of the voltage to exactly 13.8 volts and the resistor network formed by resistors R4 through R7 controls the current limiting. The LM723 limits the current when the voltage drop across R5 approaches .7 volts. To reduce costs, most commercial units rely on the HFE of the pass transistors to determine the current limiting. The fault in that system is that the HFE of the pass transistors actually increases when the transistors heat up and risks a thermal runaway condition causing a possible failure of the pass transistors. Because this circuit samples the collector current of the pass transistors, thermal runaway is not a problem in this circuit making it a much more reliable power supply.

Inductorless 3 to 5 Volts Converter

By configuring a comparator and a transistor to control the oscillator in a charge pump circuit, you enable the pump to generate a regulated output of in principle any desired value. Charge pump ICs can either invert or double an input voltage (for example, 3 V to –3 V or 3 V to 6 V). The charge pump itself does not regulate the output voltage and one running off 3 V is not normally capable of generating intermediate output voltage levels like 5 V. However, by adding a comparator and a reference device, you can create arbitrary output levels like 5 V and regulate them as well.

Inductorless 3-to-5 Volts Converter Circuit diagram :

Inductorless 3-to-5 Volts Converter Circuit Diagram

Charge pump IC1 (a MAX660) has an internal oscillator whose 45 kHz operation transfers charge from C1 to C2, causing the regulated output to rise.

When the feedback voltage (pin 3 of IC2) exceeds 1.18 V, the output of comparator IC2 (a MAX921) goes high, turning off the oscillator via T1. The comparator hysteresis (easily added on IC2) is zero here simply because no hysteresis is required in the control loop. The oscillator when enabled generates two cycles, which is sufficient to drive VOUT slightly above the desired level. Next, the feedback turns the oscillator off again.

The resulting output ripple will depend mainly on the input voltage and the output load current. Output ripple may be reduced at the expense of circuit efficiency by adding a small resistor (say, 1 ?) in series with C1. You’ll find that ripple also depends on the value and ESR associated with C1 - smaller values of C1 transfer less charge to C2, producing smaller jumps in V OUT.

High-Performance Interruption Detector Circuit Diagram

The circuit presented here detects interruption in security systems. Its features include no false triggering by external factors (such as sun-light and rain), easy relative positioning of the sensors and alignment of the circuit, high sensitivity, and reliability. The circuit comprises three sections, namely, transmitter, receiver, and power supply. The transmitter generates modulated IR signals and the receiver detects the change in IR intensity. Power supply provides regulated +5V to the transmitter and the receiver.

The power supply and the speaker are kept inside the premises while the transmitter and the receiver are placed oppo site to each other at the entrance where the detection is needed. Three connections (Vcc, GND, and SPKR) are needed from the power supply/speaker to the receiver section, while only two connections (Vcc and GND) are required to the transmitter. The transmitter is basically an astable multivibrator configured around NE555 (IC3). Its frequency should match the frequency of the detector/sensor module (36 kHz for the module shown in figure) in the receiver. The transmitter frequency is adjusted by preset VR2. For making the duty cycle less than 50 per cent, di-ode 1N4148 is connected in the charging path of capacitor C7.

The output of astable multivibrator modulates the IR signal emitted from IR LEDs that are used in series to obtain a range of 7 metres (maximum). To increase the range any further, the transmitted power has to be raised by using more number of IR LEDs. In such a case, it is advisable to use another pair of IR LEDs and 33-ohm series resistor in parallel with the existing IR LEDs and resistor R5 across points X and Y. The receiver unit consists of a monostable multivibrator built around NE555 (IC2), a melody generator, and an IR sensor module. The output of the IR sensor module goes high in the standby mode or when there is continuous presence of modulated IR signal.

High-Performance Interruption Detector Circuit Diagram

When the IR signal path is blocked, the output of the sensor module still re-mains high. However, when the block is removed, the output of the sensor module briefly goes low to trigger monostable IC3. This is due to the fact that the sensor module is meant for pulsed operation. Thus interruption of the IR path for a brief period gives rise to pulsed operation of the sensor module. Once monostable IC2 gets triggered, its output goes high and stays in that state for the duration of its pulse width that can be controlled by preset VR1. The high output at pin 3 of the monostable makes the musical IC to function. Voltage divider comprising R2 and R3 reduces the 555 output voltage to a safer value (around 3V) for UM66 operation. The du-ration of the musical notes is set by pre-set VR1 as stated earlier.

For proper operation of the circuit, use 7.5V to 12V power supply. A battery backup can be provided so that the circuit works in the case of power failure also. Potmeter VR3 serves as a volume control. The transmitter, receiver, and power supply units should be assembled separately. The transmitter and the receiver should have proper coverings (booster) for protection against rain. The length of the wire used for connecting the IR sensor module and IR LEDs should be minimum.

1 W Home Stereo Amplifier Rise

This is a one watt home stereo amplifier module project using the KA2209 IC from Samsung, which is equivalent to the TDA2822. It operates from 3-12V DC & will work from a battery since the dormant current drain is low. It requires no heat sink for normal use. The input & output are both ground referenced. Maximum output will be obtained with a 12V power supply & 8 ohm speaker, however it is suitable for driving headphones from a supply as low as 3V.

The Specifications of the home stereo amplifier :

D.C. input : 3 – 12 V at 200 – 500 mA max
Idle current : approx. 10 mA
Power output : > 1 Watt max. 4-8 ohms, 12V DC
Freq. Resp. : approx. 40 Hz to 200 kHz, 8 ohm, G=10
THD : < 1 % @ 750 mW, 4-8 ohm, 12V
Gain : approx. x10 (20 dB) OR x100 (40dB)
S/N ratio : > 80 dB, G = 20 dB
Sensitivity : < 300 mV, G = 20 dB
Input Impedance : approx. 10 k ohm

Description

The gain is adjustable from ten to 100, i.e. twenty to 40 dB. Start with feedback resistors R1 and R3 of 1k ohm, this will give a gain of ten which ought to be adequate for most applications. In case you need more gain, you can remove resistors R1 and R3.This will give a gain of about 100, or 40 dB.The input attenuation can be adjusted by the potentiometer which can be used as a volume control. The IC gain ought to be kept as low as necessary to accomplish full output, with the in put potentiometer and your signal source at maximum.

1 W Home Stereo Amplifier Circuit Diagram

Voltage Gain = 1+ R1/R2 = 1+R3/R4, however the maximum gain with no outside feedback is about 100, or 40dB. (GdB = 20log Gv)

This will keep the signal to noise ratio as high as feasible. Additional gain provided by the amplifier will reduce the S/N ratio by a similar amount, since the input noise figure is constant. Other values for R1 and R3 of between 1k and 10k ohm can be used if an intermediate gain level is necessary.

If driving a pair of headphones, you may also need a 100 ohm resistor in series with each output to reduce the output level, depending on headphone impedance & sensitivity. Make positive you start with the volume right down to check. Numerous headphones may be driven from the amplifier in the event you wish, since most headphones have at least 16 ohm impedance, or more often 32 ohm.

There are only a few outside parts, the IC contains most of the necessary circuitry. R1,R2 and R3,R4 are the feedback resistors. C1 provides power supply decoupling. C2 and C3 are the input coupling capacitors, which block any DC that might-be present on the inputs. C4,C5 block DC in the feed back circuit from the inverting inputs, and C6,C7 are the output coupling capacitors. C8, R5 and C9,R6 act as Nobel networks providing a high frequency load to maintain stability at frequencies where loud speaker inductive reactant may become excessive. The pot provides adjustable input level attenuation.

Thursday, October 16, 2014

Motorcycle Alarm With Transistor Circuit Diagram

This is a simple Motorcycle Alarm With Transistor Circuit Diagram. Its designed to work at 12-volts. But - if you change the relay for one with a 6-volt coil - itll protect your "Classic Bike". The standby current is virtually zero - so it wont drain your battery.

Motorcycle Alarm With Transistor Circuit Diagram

Motorcycle

Any number of normally-open switches may be used. Fit the mercury switches so that they close when the steering is moved or when the bike is lifted off its side-stand or pushed forward off its centre-stand. Use micro-switches to protect removable panels and the lids of panniers etc. While at least one switch remains closed - the siren will sound.

About one minute after all of the switches have been opened again - the alarm will reset. How long it takes to switch off depends on the characteristics of the actual parts youve used. You can adjust the time to suit your requirements by changing the value of C1 and/or R3.

The circuit is designed to use an electronic Siren drawing 300 to 400mA. Its not usually a good idea to use the bikes own Horn because it can be easily located and disconnected. However, if you choose to use the Horn, remember that the alarm relay is too small to carry the necessary current. Connect the coil of a suitably rated relay to the Siren output - and use its contacts to sound the horn.

The circuit board and switches must be protected from the elements. Dampness or condensation will cause malfunction. Without its terminal blocks, the board is small. Ideally, you should try to find a siren with enough spare space inside to accommodate it. Fit a 1-amp in-line fuse as close as possible to the power source. This is Very Important. The fuse is there to protect the wiring - not the circuit board. Instead of using a key-switch you can use a hidden switch; or you could use the normally-closed contacts of a small relay. Wire the relay coil so that its energized while the ignition is on. Then every time you turn the ignition off - the alarm will set itself.

When its not sounding, the circuit uses virtually no current. This should make it useful in other circumstances. For example, powered by dry batteries and with the relay and siren voltages to suit, it could be fitted inside a computer or anything else thats in danger of being picked up and carried away. The low standby current and automatic reset means that for this sort of application an external on/off switch may not be necessary.

When you set the alarm - if one of the switches is closed - the siren will sound. This could cause annoyance late at night. A small modification will allow you to Monitor The State Of The Switches using LEDs. When the LEDs are all off - the switches are all open - and its safe to turn the alarm on.

Veroboard Layout

Veroboard

Wiring diagram 1965 Ford Mustang

This is interior light wiper gauges wiring diagram of 1965 Ford Mustang. Click the picture to download.

Simple 150W Amplifier Circuit Diagram

This is the cheapest 150 Watt amplifier circuit you can make,I think.Based on two Darlington power transistors TIP 142 and TIP 147 ,this circuit can deliver a blasting 150 W Rms to a 4 Ohm speaker.Enough for you to get rocked?;then try out this.

TIP 147 and 142 are complementary Darlington pair transistors which can handle 5 A current and 100V ,famous for their ruggedness. Here two BC 558 transistors Q5 and Q4 are wired as pre amplifier and TIP 142 ,TIP 147 together with TIP41 (Q1,Q2,Q3) is used for driving the speaker.This circuit is designed so rugged that this can be assembled even on a perf board or even by pin to pin soldering.The circuit can be powered from a +/-45V, 5A dual power supply.You must try this circuit.Its working great!

The preamplifier section of this circuit is based around Q4 and Q5 which forms a differential amplifier. The use of a differential amplifier in the input stage reduces noise and also provides a means for applying negative feedback. Thus overall performance of the amplifier is improved. Input signal is applied to the base of Q5 through the DC decoupling capacitor C2. Feedback voltage is applied to the base of Q4 from the junction of 0.33 ohm resistors through the 22K resistor. A complementary Class AB push-pull stage is built around the transistors Q1 and Q2 for driving the loud speaker. Diodes D1 and D2 biases the complementary pair and ensures Class AB operation. Transistor Q3 drives the push-pull pair and its base is directly coupled to the collector of Q5.

150W Amplifier Circuit Diagram

150w amplifier circuit diagram

Notes.

Remember TIP 142 and 147 are Darlington pairs .They are shown as conventional transistors in figure for ease.So don’t get confused.Even though each of them have 2 transistors ,2 resistors and 1 diode inside ,only three pins ,base emitter and collector are coming out.Rest are connected internally.So its quite OK to assume each of them as transistor for ease.
Use a well regulated and filtered power supply.
Connect a 10K POT in series with the input as volume control if you need.Not shown in circuit diagram.
All electrolytic capacitors must be rated at least 50volts.

Power supply for this circuit.

A +40/-40 unregulated dual supply for powering this amplifier project is shown below. This power supply is only enough for powering one channel and for stereo applications double the current ratings of the transformer, diodes and fuses.

Wednesday, October 15, 2014

Burglar Alarm With Timed Shutoff Circuit Diagram

When SI (sensor) is closed, power is applied to U2, a dual timer. After a time determined by C2, CI is energized after a predetermined time determined by the value of C5, pin 9 of U2 becomes low, switching off the transistor in the optoisolater, cutting anode current of SCR1 and de-energizing Kl. The system is now reset. Notice that (i6x C2) is less than (R7xC$). The ON time is approximately given by:(R7xC5)-(R6xC2) = Ton

Burglar Alarm With Timed Shutoff Circuit Diagram

Simple DPA 220 schematic

T1 to T6 create the input differential stage. The D7 and D8 zener diodes stabilize at 5V. These are just the simplest low-power zeners, only they have to be coupled in tolerance of 200 milivolts, which should not be a problem. T1 to T6 are common all-purpose low-power transistors with high Hfe. These six and maybe the next four have to be coupled in tolerance of 25%.

The T7 and T8 are fast, switching application types.

T9 and T10 have to be fast and must hold a high voltage, thus the best are the "video" types - BF469/470. T15 and T16 are the same types.

The C9, C10 and C15 should stand voltages higher than usual 50 V - I dont know why.

D3 to D6 can be any silicon type, not Scottky, the ones listed below are just all-purpose low-current ones for 150 V. These diodes should be rather fast - "switching types".

The T11 and T12 stabilize the BIAS current for the power stage. T11 also serves as a temperature sensor, and is mounted to the cooler of power transistors.

T13 and T14 secure the output current - in cooperation with R38 and R39.

The output transistors used here are Tesla types - Tesla is a former local devices manufacturer - the pair in each branch can be replaced with a single power darlington, like BD649/BD650. They should have Pc > 150W, Ic > 15A, Uceo > 100V.

In this case obviously the R38+R40 / R39+R41 must be connected parallel. These resistors should be able to absorb high power - at least 2 W, but Id use 5W ones.

The output filter improves stability of the amp when working with complex impedance of speakers - it is quite important. The resistors are high-power ones again, the coil is 13 turns of a 1.2 mm wire on a 8 mm thorn (diameter). R43 is placed coaxially in the coil.

The schematic also includes power supply capacitors and rectifier - the capacitors size is not crucial, generally the bigger the better. The rectifier originally consists of four silicon 10A diodes, but you can use whatever you have - rectifier bridge etc. The trafo should be a 2 * 30 V / 7 A type so that you have +/- 40 V on the power supply capacitors.

In the scheme theres also a thermistor that is supposed to be connected to some additional circuits that secure temperature and other things. The complementary input stage of DPA amps is an unmistakable heir of earlier designs published by Mr. Borbely in several issues of Volume 1984 of the Audio Amateur.

Phase Controlled Dimmer Circuit Diagram

A phase-controlled dimmer delays the triac turn-on to a selected point in each successive ac half cycle. Use this circuit only for incandescent lamps, heaters, soldering irons, or universal motors that have brushes.

Phase Controlled Dimmer Circuit Diagram

Phase

Monday, October 13, 2014

Volvo 700 B230K Engine Ignition System Wiring Diagram

During the production between 1982–1990, the Volvo 700 series (760, 740, 780) were available in many different engine types and capacities, among others are 2.3 L B23ET 173 hp (129 kW) turbo I4; 2.3 L B230FT 156/165 hp turbo I4; 2.8 L B280F 147 hp V6 and 2.4 L D24TIC 115 hp (86 kW) turbo diesel I6. Below schematic depicts the 1982 Volvo Volvo 700 B230K Engine Ignition System Wiring Diagram.

Volvo

1. Battery
2. Ignition Switch
4. Ignition Coil
5. Distributor
6. Spark Plugs
11. Fuse box
29. Positive Terminal Board
81. AC Pressure Switch
86. Rev Counter
156. Radiator Fan Motor
200. AC Compressor Solenoid
202. Climate Control
218. Knock Sensor

224. Radiator Fan Thermostat
260. Control Unit
267. Test Connector
271. Fuel Cut-off Solenoid
272. Micro switch
273. Temperature Sensor
293. Idling Compensation relay
419. Power Stage
A. Connector, RH A-Post
B. Connector, LH A-Post
C. Connector, at LH Wheel Housing
D. Ground Terminal on Intake Manifold
E. Connector at LH Wheel Housing

Latest new Oxygen Sensor Simulator Oxygen Simulator Sensor

The schematic diagram for the simulator. Closing the switch engages the simulator. Turning the knob clockwise simulates a lean condition, turns the LED off, and the car should start running rich to compensate. The big "V" is a digital voltmeter (not shown in the pictures). Using a smaller value for C1, perhaps 4.7 uF, will make the circuit oscillate faster and might be more like a real oxygen sensor (a new sensor switches more often than an old one).

The schematic diagram for the simulator. Closing the switch engages the simulator. Turning the knob clockwise simulates a lean condition, turns the LED off, and the car should start running rich to compensate. The big "V" is a digital voltmeter (not shown in the pictures). Using a smaller value for C1, perhaps 4.7 uF, will make the circuit oscillate faster and might be more like a real oxygen sensor (a new sensor switches more often than an old one).

The schematic diagram of the adapter cable and oxygen sensor. Note the heater is shown as a resistor, mine measured about 7 ohms.

Power Monitor Circuit Diagram

Here is a simple non-contact AC power monitor for home appliances and laboratory equipment that should remain continuously switched-on. A fuse failure or power breakdown in the equipment going unnoticed may cause irreparable loss. The monitor sounds an alarm on detecting power failure to the equipment. The circuit is built around CMOS IC CD4011 utilising only a few components. NAND gates N1 and N2 of the IC are wired as an oscillator that drives a piezobuzzer directly. Resistors R2 and R3 and capacitor C2 are the oscillator components. The amplifier comprising transistors T1 and T2 disables the oscillator when mains power is available. In the standby mode, the base of T1 picks up 50Hz mains hum during the positive half cycles of AC and T1 conducts.

Non-Contact Power Monitor Circuit diagram:

Non-Contact Power Monitor circuit diagram

This provides base current to T2 and it also conducts, pulling the collector to ground potential. As the collectors of T1 and T2 are connected to pin 2 of NAND gate N1 of the oscillator, the oscillator gets disabled when the transistors conduct. Capacitor C1 prevents rise of the collector voltage of T2 again during the negative half cycles. When the power fails, the electrical field around the equipment’s wiring ceases and T1 and T2 turn off. Capacitor C1 starts charging via R1 and preset VR and when it gets sufficiently charged, the oscillator is enabled and the piezobuzzer produces a shrill tone. Resistor R1 protects T2 from short circuit if VR is adjusted to zero resistance.

The circuit can be easily assembled on a perforated/breadboard. Use a small plastic case to enclose the circuit and a telescopic antenna as aerial. A 9V battery can be used to power the circuit. Since the circuit draws only a few microamperes current in the standby mode, the battery will last several months. After assembling the circuit, take the aerial near the mains cable and adjust VR until the alarm stops to indicate the standby mode. The circuit can be placed on the equipment to be monitored close to the mains cable.

Sunday, October 12, 2014

Stereo FM Transmitter Based BH1417 Chips diagram

Stereo FM Transmitter Based BH1417 Chips

This electronic circuit is a latest BH1417 FM Transmitter design from RHOM that includes a lot of features in one small package. It comes with pre-emphasis, limiter so that the music can be transmitted at the same audio level, stereo encoder for stereo transmission, low pass filter that blocks any audio signals above 15KHz to prevent any RF interference, PLL circuit that provides rock solid frequency transmission (no more frequency drift), FM oscillator and RF output buffer.

There are 14 possible transmission frequencies with 200KHz increments that users can select with a 4-DIP switch. Lower band frequencies start from 88.7 up to 89.9 MHz, and upper band frequencies start from 107.7 up to 108.9 MHz.

BH1417 can be supplied with 4 - 6 voltage and consumes only around 30mA, providing 20mW output RF power. BH1417 provides 40dB channel separation which is pretty good, although older BA1404 FM Transmitter chip provides slightly better 45dB channel separation.

BH1417 is only available in SOP22 IC case so this may be an inconvenience for some folks. On the other hand, because the chip is smaller than regular DIP-based ICs it is possible to fit the entire transmitter on a small PCB.

The bad news is that BH1417 requires 7.6MHz crystal oscillator, which is very hard to find. The good news is that you can use 7.68 MHz crystal instead, which is easier to find. In fact our BH1417 transmitter prototype (schematic shown above) uses 7.68 MHz crystal. This has absolutely no effect on stereo encoding process, we have tested it and stereo sound is crystal clear. The transmitted frequency on the other hand will be shifted up by exactly 1MHz (example: 88.1 MHz to 89.1 MHz) which is perfectly fine. The frequencies that are used in this project have been adjusted by 1MHz already so no additional conversion is necessary.

BH1417 chip may also be used a stand alone stereo encoder. The advantage of that is that you have full freedom of using a transmitter & amplifier of your choice. You will still have a pre-emphasis, limiter, stereo encoder and low pass filter in one small package because very few external components are required for these blocks. PIN 5 is MPX output that can be directly connected to an external FM transmitter through a 10uF cap.

Parts List:
1x BH1417 - Stereo PLL Transmitter IC (Case SOP22) (datasheet)
1x 7.68 MHz Crystal
1x MPSA13 - NPN Darlington Transistor
1x 2.5 Turns Variable Coil
1x MV2109 - Varicap Diode
1x 4-DIP Switch
ANT - 30 cm of copper wire

1x 22K Resistor
7x 10K Resistor
1x 5.1K Resistor
2x 3.3K Resistor
1x 100 Ohm Resistor 1x 100uF Capacitor
3x 10uF Capacitor
2x 1uF Capacitor

1x 47nF Capacitor
3x 2.2nF Capacitor
1x 1nF Capacitor
1x 330pF Capacitor
2x 150pF Capacitor
1x 33pF Capacitor
2x 27pF Capacitor
1x 22pF Capacitor
2x 10pF Capacitor

Specifications:
Supply Voltage: 4 - 6V
Transmission Frequency: 87.7 - 88.9MHz, 106.7 - 107.9MHz (200kHz steps)
Output RF Power: 20mW
Audio Frequency: 20 - 15KHz
Separation: 40dB
Power Consumption: 30mA

Frequency Selection / Calibration
Frequency selection is very straight forward. Simply select transmission frequency at which you would like to transmit, set the combination for 4-DIP switch and BH1417 will immediately tune to that frequency. If you cant hear the transmitted audio signal on your FM receiver then re-adjust 2.5 turn variable coil until you can hear the signal. If you have a laboratory power supply you may try to vary the voltage supply from 4 to 6V. While doing that BH1417 will automatically vary the voltage for MV2109 varicap diode making sure that theres no frequency drift.

Power Supply 5V 1 3 3A by LM2575

Power

POWER1 is a switched power supply specially designed for use with modern single board computers. The mechanical dimensions match exactly those of the SBC ZWERG11A. Due to the small mechanical dimensions and the modern design, POWER1 can be used in all applications requiring a regulated voltage of 5 Volts DC, up to 3 Amperes. Voltage regulation is done with a component from National Semiconductor, known as “simple switcher”. Regarding the amount of extra components one can really call the design “simple”, yet resulting in a reliable and low-cost power supply.

Read More Source:

http://www.mct.net/product/power1.html

Friday, October 10, 2014

FAN302HL bassed 5 volt switching power supply circuit project

FAN302HL

FAN302HL

A very simple 5 volt switching power supply electronic circuit project can be designed using FAN302HL highly integrated PWM controller integrated circuit, that provides several features to enhance the performance of general flyback converters.
The constant-current control, of the FAN302HL proprietary topology enables simplified circuit designs without secondary feedback circuitry for battery charger applications.
This 5 volt switching power supply electronic circuit project accepts a wide range input voltage from 90 to 265 VAC and will provide a 5 volt regulated output at a maximum output current of 1.2 ampere .
A proprietary Burst-Mode function with low operation current minimizes standby power consumption.

The FAN302HL controller also provides several like protections : VDD Over-Voltage Protection (Auto-Restart) ,VS Over-Voltage Protection (Latch Mode) , Fixed Over-Temperature Protection .
The most difficult part that is require in this project is the transformer.
W1 is four winds; for each wind of turns, refer to table bellow. Add one insulating tape between the first and second layers.
W2 is wound two layers and uses triple-insulated wire: end of positive fly line is 3.5cm, layer end of negative fly line is 2.5cm.
W3 is spares winding in one layer.
W4 is wound in the core of the outermost layer and sparse winding.

Thursday, October 9, 2014

Circuit measurements temperature by diode 1N4148

measurements temperature by diode 1N4148

temperature by diode 1N4148 and ic 741.
easy to make and use.
Out to Voltmeter.
*** Low cost too !

When I wants the circuit takes the temperature to are simple. I uses Diode 1N4148 be formed check the temperature. By when feed voltage change it. It is have current flow be stable. When the temperature that Diode, change make Voltage. At it modifies with VR1 and VR2 fine decorate for show that is correct most fining decorates. The important I uses the temperature certainly compare with accurate temple. By compare with reserve 0 the degree Celsius per 0 Volt. For the certainty advises that, should use Digital Voltage Meter. Show well almost forget the important point should. Give power supply Regulator high-quality , such as IC 7815 and IC 7915 etc. Try usable this circuit sees, regard good base of the circuit takes the temperature sir.

latest circuit and explanation of Basic UPS Power Supply

Circuit : Andy Collinson
Email: anc@mitedu.freeserve.co.uk

Description
This circuit is a simple form of the commercial UPS, the circuit provides a constant regulated 5 Volt output and an unregulated 12 Volt supply. In the event of electrical supply line failure the battery takes over, with no spikes on the regulated supply.

UPS

Notes:
This circuit can be adapted for other regulated and unregulated voltages by using different regulators and batteries. For a 15 Volt regulated supply use two 12 Volt batteries in series and a 7815 regulator. There is a lot of flexibility in this circuit.
TR1 has a primary matched to the local electrical supply which is 240 Volts in the UK. The secondary winding should be rated at least 12 Volts at 2 amp, but can be higher, for example 15 Volts. FS1 is a slow blow type and protects against short circuits on the output, or indeed a faulty cell in a rechargeable battery. LED 1 will light ONLY when the electricity supply is present, with a power failure the LED will go out and output voltage is maintained by the battery. The circuit below simulates a working circuit with mains power applied:

mains

Between terminals VP1 and VP3 the nominal unregulated supply is available and a 5 Volt regulated supply between VP1 and VP2. Resistor R1 and D1 are the charging path for battery B1. D1 and D3 prevent LED1 being illuminated under power fail conditions. The battery is designed to be trickle charged, charging current defined as :-

(VP5 - 0.6 ) / R1
where VP5 is the unregulated DC power supply voltage.

D2 must be included in the circuit, without D2 the battery would charge from the full supply voltage without current limit, which would cause damage and overheating of some rechargeable batteries. An electrical power outage is simulated below:

power

Note that in all cases the 5 Volt regulated supply is maintained constantly, whilst the unregulated supply will vary a few volts.

Standby Capacity
The ability to maintain the regulated supply with no electrical supply depends on the load taken from the UPS and also the Ampere hour capacity of the battery. If you were using a 7A/h 12 Volt battery and load from the 5 Volt regulator was 0.5 Amp (and no load from the unregulated supply) then the regulated supply would be maintained for around 14 hours. Greater A/h capacity batteries would provide a longer standby time, and vice versa.

Circuit Switching Regulators Using LM2575 and LM2577

Switching regulators are available is different circuit configurations including the flyback, feed-forward, push-pull, and non-isolated single-ended or single-polarity types. Also, the switching regulators can operate in any of three modes – step-down, step-up, or polarity inverting.
rovide the active functions for step-down (back) switching regulator, capable of driving a1A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, 15V and an adjustable output version.

Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation and a fixed-frequency oscillator. LM 2575 series offers a high-efficiency replacement for popular 3-terminal linear regulators. It substantially reduces the size of the heat sink, and in many cases no heat sink is required. Fixed output voltage version is illustrated in figure.

The National Semiconductor LM 1577/LM 2577 are monolithic ICs that provide all of the power and control functions for step-up (boost), fly back, and forward converter switching regulators. The device is available in three different output voltage versions: 12 V, 15 V and adjustable.

Simple Toy Organ Circuit based Timer IC 555

This is a very simple toy organ circuit which built based timer IC 555. It only contains of several components, even a newbie can build this circuit easily. This circuit generates a tone according to the button being pressed.

This easy build toy organ can be powered with 6V battery supply or commonly general purpose power supply. Only 1 button can be pressed at a time, that’s why it is called a monophonic organ. You can change the 1k resistors to produce a more-accurate scale. You also can add new tones by add some switchs and 1k resistors. If you need a louder sound, you can add an amplifier on the output.

Wednesday, October 8, 2014

Low Cost Fire Alarm Circuit and explanation Using Transistor

Transistor BC177 (Q1) is used as the fire sensor here. When the temperature increases the leakage current of this transistor also increases.The circuit is designed so that when there is an increase in the leakage current of Q1, transistor Q2 will get biased. As a result when there is a fire breakout the transistor Q2 will be on. The emitter of Q2 (BC 108)is connected to the base of Q3(AC 128). So when Q2 is ON Q3 will be also ON. The transistor Q3 drives the relay which is used to drive the load ie,light,bell,horn etc as an indication of the fire. The diode D1 is used as a free wheeling diode to protect it from back EMF generated when relay is switched.

Notes:

The Preset R1 can be used to desired temperature level for setting the alarm ON.
This is not a latching alarm,ie; when the temperature in the vicinity of the sensor decreases below the set point the alarm stops.
The circuit can be powered using a 9V battery or a 9V battery eliminator.
All capacitors are electrolytic and must be rated at least 10V.
The load can be connected through the C,NC,NC points of the relay according to your need.
The calibration can be done using a soldering iron,and a thermo meter. Switch ON the power supply.Keep the tip of soldering iron near to the Q1.Same time also keep the thermometer close to it.When the temperature reaches your desired value adjust R1 so that relay gets ON.

LM1877 bassed Audio power amplifier circuit and explanation

Using the LM1877 monolithic dual power amplifier can be designed a very simple audio amplifier circuit for small audio applications like portable devices .

This audio amplifier circuit is designed to deliver 2W per channel continuous into 8Ω loads. The LM1877 is designed to operate with a low number of external components, and still provide flexibility for use in stereo phonographs, tape recorders and AM-FM stereo receivers, etc.
Each power amplifier is biased from a common internal regulator to provide high power supply rejection, and output Q point centering. The LM1877 is internally compensated for all gains greater than 10.

This audio amplifier circuit can be powered from a wide input voltage range from 6 volt up to 24 volts .
For this audio power amplifier circuit diagram you must use a 8 ohms speaker .

Sunday, October 5, 2014

Circuit digital clock circuit,

The figure on the right is displaying the condition to be displaying 10:32:54 p.m. switching every 500 milliseconds. In the switching time of the actual circuit, it is 1 millisecond. So, all digit sees to be displayed at the same time. The light of the LED is 1/6 compared with the continuation lighting-up. The specification of the display position is controlled by the binary signal which is output from RA0, RA1 and RA2 port of PIC.

This signal is decoded in CPLD and eight kinds of signals are made. This time, six kinds are used. Only the transistor which corresponds to the L level decoder output becomes ON condition. The LED which is connected with the transistor becomes a lighting-up possible condition. In the tens-hour display, only “1″ is displayed. So, I put the display of AM/PM. 74HC138 can be used for the 3-8 decoder, too. Segments of the lighting-up of each digit are controlled using 7 ports of RC6 from RC0 of PIC. The output of these ports is common to all the LEDs.

However, only the LED of the digit which was specified by RA0-2 is controlled in the lighting-up. The LED lights up when the RC port is an L level. The brightness of the LED depends on the kind of the LED. When the brightness is different extremely, the resistors which are connected with the RC ports should be separated. This time, because it is approximately the same brightness, resistors are made common. Because the maximum voltage which is applied to the pin of PIC is 5V, I make the power of the LED 5V.

2N3055 TIP41 CA3140 Lab Power Supply 0 30V 2A

This is the schematic of the 30V/2A power supply I use in my own lab.It may look very complex, but it really isn’t very difficult to understand: it uses only the knowledge we’ve learned in the previous lessons.
The top part looks like the power supply we built in Lesson 7: the transformer L1 transforms the outlet voltage to a safe 30V, which is rectified by bridge rectifier G2 and smoothed by capacitor C5. Transistors T3 and T6 form a darlington transistor. This darlington replaces transistor T1 in Lesson 7. However, the base voltage is not controlled by a simple potmeter, but by an ‘electronic potmeter’ with voltage feedback. The advantage of this feedback is a load-independent output voltage.

LM317 Overvoltage Protection Circuit

It is a voltage regulator that allows a 6v carriageable accumulation to be acquired from the 12v car battery. You can add a 6.2V zener diode and a LED to acquaint you back the ascribe accumulation is overvoltage. If you could acquisition a broadcast that would accomplish from 6.2v appropriate up to 12v that you could affix in such a way that if over voltage occurred, again the broadcast would automatically about-face off the achievement preventing accident to any affiliated equipment.

Such a broadcast would be absolutely difficult to find, so I advised this, it is a simple two transistor ambit which will about-face off the achievement should the voltage accession aloft 6.2v (this can be afflicted by selecting a altered amount of zener diode ).

Components are as follows:

ZD1 =3D 6.2v Zener diode (you can change this to any value, the ambit will about-face off the achievement if the ascribe voltage raises aloft the amount of the zener diode)

R1 = 1K Resistor (this can be of any ability rating, it carries actual little power)

R2 = 1K Resistor (this can be of any ability rating, it carries actual little power)

T1 = Low ability NPN Transistor (BC108 or BC547 will do fine)

T2 = NPN transistor transistor able of switching the accessories you are active (BFY51 or BC140 can about-face 1 Amp, which is the best the voltage regulator ambit can handle)

It is appropriate to analysis this ambit with a voltmeter, boring accretion the voltage on the regulator ambit and accomplish abiding that this ambit switches off the achievement back the amount of the zener diode is reached, afore active in your big-ticket equipment. This ambit is advised to be acclimated with the voltage regulator acquaint by Matthew Hewson, my overvolatge add-on ambit is apparent with the aboriginal below:

LM317

LM317 Overvoltage Protection Circuit

Saturday, October 4, 2014

500W low cost 12V to 220V Inverter

Using this circuit you can convert the 12V dc in to the 220V Ac. In this circuit 4047 is use to generate the square wave of 50hz and amplify the current and then amplify the voltage by using the step transformer.

Attention: This Circuit is using high voltage that is lethal. Please take appropriate precautions

How to calculate transformer rating

The basic formula is P=VI and between input output of the transformer we have Power input = Power output

For example if we want a 220W output at 220V then we need 1A at the output. Then at the input we must have at least 18.3V at 12V because: 12V*18.3 = 220v*1

So you have to wind the step up transformer 12v to 220v but input winding must be capable to bear 20A.

SG3524 PWM Inverter Circuit 250W

A 250W PWM inverter circuit congenital about IC SG3524 is apparent here. SG3524 is an chip switching regulator circuit that has all capital chip appropriate for authoritative a switching regulator in individual concluded or push-pull mode. The congenital in circuitries central the SG3524 cover beating amplitude modulator, oscillator, voltage reference, absurdity amplifier, afflict aegis circuit, achievement drivers etc.

SG3524 forms the affection of this PWM inverter ambit which can actual its achievement voltage adjoin the variations in the achievement load. In a non PWM inverter the change in achievement amount anon affects the achievement voltage (when achievement amount increases achievement voltage decreases and carnality versa), but in a PWM inverter the achievement voltage charcoal connected over a circuit of achievement load.

1 5 Volt Tracking Transmitter

1.5

The current draw for this tracker is 3.7mA, so the 1.5V button cell will last awhile. What the heck am I suppose to hear you ask? When your circuit is working you should see the LED flash quite fast. Take your FM radio and search for the low-beat humbe-humbe-humbe-etc equal to the flash of the LED (probably around the 100Mhz). Found it? If that position is interferering with a radio station you can fine-tune it with the variable capacitor.

If you like to have the tracker around the 88Mhz you can do that by spreading the windings from the home-made coil just a bit (1/2 a millimeter or so). Anyways, play with it and learn. It is a nice project. The 12-inch antenna can be anything, it is not really that critical. I used a piece of 22 gauge flexible wire. I havent checked the range but will do that shortly.

* For stability, use a NPO types for C2 & C4.
* Resistance tolerance for R1 should be 1 or 2%.
* Frequency range is the usual 87-109Mhz on the FM dial.
* The coil is made from 22 ga hookup wire, like the solid Bell phone wire. Leave the insulation on.
* The LED is the High Brightness type for maximum illumination.

Partlist
C1= 100uF electrolytic capacitor
C2= .01uF disc capacitor
C3= 4 to 40 pF trimmer capacitor
C4= 4.7 pF trimmer capacitor
L1= 0.1 uH, 6 to 8 turns of 22 gauge hookup wire close wound around a 1/4" diameter non-conductive core, such as pencil
IC1= LM3909 LED flasher
LED1= Red LED
Q1= 2N3904 NPN silicon transistor
R1= 10K
Antenna= 10 to 12 inches of hookup wire

Friday, October 3, 2014

Ramp Generator Circuit using NE555

We know that if a capacitor is charged from a voltage supply through a resistor, an exponential waveform is created while charging of a capacitor from a continuing current supply produces a ramp. this is the concept behind the circuit. The circuit of a ramp generator using timer 555 is shown in figure. Here the resistor of previous circuits is replaced by a PNP transistor that produces a continuing charging current.

Charging current produced by PNP constant current source is

i_C= Vcc-V_E/ R_E

where V_E= R₂/ (R1 + R2) * V_CC+ V_BE

When a trigger starts the monostable multivibrator timer 555 as shown in figure, the PNP current supply forces a continuing charging into the capacitor C. The voltage across the capacitor is, therefore, a ramp as illustrated in the figure. The slope of the ramp is given as Slope, s = I/C

Thursday, October 2, 2014

Circuit Diagram FM Antenna Booster

FM Antenna Booster Circuit Diagram

This is a low cost fm antenna booster that can be used to listen to programmes from distant FM stations clearly. The antenna fm booster circuit comprises a common-emitter tuned RF preamplifier wired around VHF/UHF transistor 2SC2570 (C2570).

Assemble the circuit on a good-quality PCB (preferably, glass-epoxy). Adjust input/output trimmers (VC1/VC2) for maximum gain.

Input coil L1 consists of four turns of 20SWG enamelled copper wire (slightly space wound) over 5mm diameter former. It is tapped at the first turn from ground lead side. Coil L2 is similar to L1, but has only three turns. Pin configuration of transistor 2SC2570 is shown in the fm antenna booster schematic.

Dark Room Timer Circuit

Working in a darkroom is always fraught with problems. You surely know Murphys Law of. . .,
but Let’s not go into that here. Suffice it to say that normal lights cannot be used in a darkroom when photographs are being developed not even if you drop your glasses! The circuit here is a simple, inexpensive design for a darkroom torch (or light) that can be mounted in a case small enough to fit into your pocket even with a 9 V battery included. It gives enough light for note-taking or finding this or that in a darkroom, but the light is emitted by three special yellow LEDs which can safely be used near black/white or colour paper. Red LEDs are used for orthochromatic material (we had to look it up too, it means giving correct relative intensity to colours in photography!). An energy saving circuit is included that automatically switches the lamp off when the ambient light is above a certain level. The diagram for the circuit makes it look like a mini power supply. When the circuit is switched on with S1 T2 conducts and provides, in turn, a base drive current to transistor T1. This transistor then supplies the base current for T2 via R5 and P1. i Switching S‘l off causes C1 to deliver a negative pulse to the base of T2 and this transistor then stops conducting.

Tl also stops conducting and the LEDs go out. The energy saving circuitry requires the addition of just one component, the LDR. When enough light falls on it the LDRs resistance causes T2 to switch off and extinguish the LEDs. The Iight level at which this happens is set by means of preset P1 Q LEDs D3 . . . D5 must be high efficiency types and are either red or yellow depending on what sort of photographic paper is used. There are various high intensity LEDs available, although the light intensity level can also be changed by varying the current flow through T1 (by substituting another value of resistor for R1 ). With the values stated about 20 mA flows through the LEDs and, seeing as the current consumption when the LEDs are off is only a few nA, the 9 V battery should last quite a while. Finally it is important to remember that some types of photographic paper are sensitive to all colours, including red and yellow, so check this before using the lamp.

Wednesday, October 1, 2014

True RMS Detector Circuit

To get an RMS value when you cant afford the time it takes to heat an element, try this technique. It may not be feasible for a multimeter but how about a sampling voltmeter good up to 600 kHz?
Mathematically, the RMS value of a function is obtained by squaring the function, averaging it over a time period I` and then taking the square root:

Vrms = root of (1/T integrated from 0 to t * V^2dt)

ln a practical sense this same technique can also be used to find the RMS value of a waveform. Using two multipliers and a pair of op amps, an RMS detector can be constructed. The first multiplier is used to square ts. input waveform. Since the output of the multiplier is a current, an op amp is customarily used to convert this output to a voltage. The same op amp may also be used to perform the averaging function by placing a capacitor in the feedback path. The 1 second op amp is used with· a multiplier as the feedback element to produce the square root configuration. This method eliminates the thermal-response time that is prevalent in most RMS measuring circuits. The input voltage range for this circuit is from 2 to 10 Vpk. For other ranges, input scaling can be used. Since the input is dc coupled, the output voltage includes the dc components of the input waveform.

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