Build a Isolated 15V To 2500V Power Supply Circuit Diagram

Build a Isolated 15V To 2500V Power Supply Circuit Diagram. A dc-dc converter using a 74HC04 drives Tl. Tl is a ferrite-core transformer using a Fair-Rite, Inc. P/N 5975000201 (uo + 5000) and has a 7-turn primary and a 25-turn secondary. Kynar, #30 wirewrap wire is used. With Tl, the circuit isolation is good to 2500 V.

Isolated 15V To 2500V Power Supply Circuit Diagram

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Ground free DVM Module Supply from 5 V

The majority of hand-held digital volt meters use an LCD screen and are powered from a nine volt battery. Inside is most probably an ICL7106 chip (or something compatible). This takes care of measuring the input and driving the LCD. This IC is very popular and can be found in other laboratory and homebrew equipment where it offers a simple solution for both measuring current/voltage and driving the display.

So far so good, there is how-ever one feature of this device which needs careful consideration. The power supply to the chip (both the positive and negative connection) must not have any direct connection to either of the two measuring input terminals. It requires floating supplies. This is not a problem for battery powered equipment but needs more thought when the ICL7106 is fitted into mains powered equipment.

Ground-free DVM Module Supply from 5 V Circuit Diagram :

The simplest, most expensive solution is to use two independent power supplies in the equipment. A battery could also be used as an isolated supply but in a mains powered device it would seem a bit out of place and inconvenient.

In this case the term ‘floating supplies’ means that it is possible to have two separate DC levels. This level of isolation can be achieved with capacitors to separate the two DC supplies. Back in 2003 we published a circuit in the July/August edition of Elektor (circuit number 75) which used a NE555 IC. Unfortunately this design required a supply voltage upwards of 10 V. If the DVM module is fitted to equipment which only uses a 5 V supply (as is often the case) the circuit will not be of much use.The author has solved the problem by modifying the original circuit, using a hex Schmitt trigger inverter type 74HC14N instead of the NE555. One of the inverters generates a square wave of about 75 KHz. The remaining five inverters are wired in parallel to pro-vide more output drive current for the voltage multiplier stage.

DC isolation is provided by capacitors C2 and C3. A classic voltage multiplier configuration is made up of capacitors and diodes. The circuit generates an output of around 8.5 V at a load current of 1 mA. This is sufficient to power the DVM chip. The 5 V supply for the circuit must be stabilised.

The values of the input voltage divider resistors R2 and R3 are independent of the chip’s power supply and must be selected according to the desired measurement range.

Source :  http://www.ecircuitslab.com/2012/09/ground-free-dvm-module-supply-from-5-v.html

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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

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

 

 

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Latch Up Alarm Using Opto Coupler

The latch-up alarm described here is based on single IC NE555, configured as an astable multivibrator. The timing components are selected such that the oscillation frequency of the multivibrator lies within the audio range. Instead of a flip-flop stage, an opto-coupler (MCT2E) is used for latching of the alarm.  Under normal condition, pin 4 of IC1 is pulled to ground via resistor R2, and its output at pin 3 is held  ‘low’. When switch S1 is pressed momentarily, transistor T1 conducts to bring reset pin 4 of 555 to logic  ‘high’. As a result, IC1 is activated and the alarm starts to sound.

 
Latch-Up Alarm Using Opto-Coupler Circuit Diagram

 

Simultaneously, the LED inside opto-coupler glows and the phototransistor conducts. As a result, trigger transistor T1 gets base bias via phototransistor and resistor R6. The alarm sounds continuously until reset switch S2 is pressed. When switch S2 is pressed, transistor T1 is switched  ‘off’ to bring pin 4 of IC1 to logic ‘low’ and the alarm is disabled.

Source:   http://www.ecircuitslab.com/2012/01/latch-up-alarm-using-opto-coupler.html

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It is unnecessary for the customer to stop the use

It is unnecessary for the customer to stop the use of cell phone jammer .
There are some mobile phones which are having many advanced features and so their cost is high. However, you can find several cheap mobile phones available in the UK market online mobile phone shops give you the latest brands from the prominent manufacturers at a very competitive price offer. The worst of it is that others use it to send objective answers to those in the examination hall, which may not be correct at the end of the day. This can end the students career if caught, as exam malpractice is a punishable offense.
In the end, I had to fork out a sum of $200 to clean up the mould and to get the mobile phone functioning again some 3 months later, because by the time it was repaired, I was back in Australia and had to get a friend to retrieve it for me.
Now, the lesson of this experience is simple - Read the fine print of your warranty that comes with every purchase of your mobile phone.Just because what you buy is an established brand, never ever assume that its design is built to keep out the moisture or that it would not become mouldy inside, not even if it is a Sony. I was told it was standard policy to treat mouldy conditions within the mobile phone as a result of improper use of the mobile phone, rendering any warranty void.
While the mobile phone was a newer model, and I had always considered it an important part of my professional tools, there was never any case of mis-use of the mobile phone that could have allowed water to seep inside the mobile phone. If there was any mould, it would only have been the change of weather from the country of purchase and the country of use.
Let my experience be your guide, and pay attention to the fine print of your warranty so that you are sure whether mouldy conditions are covered under the warranty especially if you are going to use a mobile phone purchased overseas where there are different climatic conditions.
Avoid buying a lemon when you are shopping for a newer mobile phone. Visit your local Australian and New Zealand mobile phones online store Aussie Mobile Phones Store [http://aussie-mobilephones.reviewadvisors.info] for free resources and to view the latest in mobile phones for the Australian and New Zealand region. Updated daily, the website has a vast array of mobile phones on offer for the discerning user, and provides an online shopping experience with a difference.
Secondary school is a term used to describe an educational institution where the final stage of schooling, known as secondary education and usually compulsory up to a specified age, takes place. It follows elementary or primary education, and may be followed by university (tertiary) education.

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Cat and Dog Repeller

Nowadays, just about every house has an outside lamp with a motion sensor. Such a device eliminates the need to feel your way to the front door, and it apparently also scares away intruders. The only problem is that free-running dogs and cats in the neighborhood have little regard for such lamps and continue to deposit their excrement in the garden, once they have found a habitual location there for this purpose. This gave rise to the idea of connecting a sort of siren in parallel with the outside lamp to clearly advise dogs and cats that they are not welcome.

Naturally, it would be nice to avoid startling the entire neighborhood with this alarm signal. Here we can take advantage of the fact that dogs and cats have a significantly better sense of hearing than people. Not only are their ears more sensitive, they can also perceive significantly higher frequencies. With people, the upper limit is around 18 kHz, but dogs and cats can hear frequencies in excess of 20 kHz. We can take advantage of this by building a siren that emits a frequency just above 20 kHz.

Cat and Dog Repeller Circuit diagram :

This will scare off dogs and cats, but people will simply not hear it. All we need for this is an oscillator with an amplifier stage and a tweeter that can reproduce such high frequencies, such as a piezoelectric tweeter. The schematic diagram shows how easily this can be implemented. The power supply for the entire circuit is formed by the components up to and including C2. The 230-V leads are connected in parallel with the motion-sensor lamp. C1 and R1 provide capacitive coupling to reduce the 230 V to an acceptable voltage. 

A DC voltage of approximately 9.1 V is generated from this voltage using a bridge rectifier and D1, filtered and buffered by C2. The oscillator is built around R3, C3 and IC1a.The frequency of this oscillator is rather dependent on the specific characteristics of IC1, so the values shown here should be regarded as guidelines. If the oscillator frequency is too high, it can be reduced by increasing the value of R3 and/or C3.

If the frequency is too low (which means that the siren tone it is audible), the value of R3 and/or C3 should be increased. The square-wave signal from the oscillator is applied to the input of an H bridge composed of several Schmitt triggers in combination with the final output stages (T1–T4). This approach causes the peak-to-peak value of the square wave signal to be twice the supply voltage. As a result, a respectable 18 V is obtained across the piezoelectric tweeter, which is sufficient to produce a quite loud whistle tone. When building the circuit, you should bear in mind that it is directly powered from 230 V and not electrically isolated from the mains network.

It is thus necessary to avoid contact with all of the components when the circuit is in use. In practice, this means that the circuit must be fitted into a well-insulated, waterproof box. If you want to test the circuit, it is a good idea to first discharge C1 using a resistor, since it can hold a dangerous charge. You must also ensure that components F1, C1, R1 and B1 all have a mutual insulation separation of at least 6 mm!

Source : www.ecircuitslab.com/2011/05/cat-and-dog-repeller.html

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3V Low Battery Voltage Flasher

Many battery powered devices use two AA alkaline cells.  Often you will not know when it is time to replace the batteries until the device powered by them actually stops operating.  The hobby circuit below can be connected to a 3v battery, to give you some warning when the battery is nearing its end of life. It will flash a LED when the battery voltage drops to about 2.4 volts.

The electronic circuit draws only 1ua of current in standby mode and jumps to only 20ua when flashing, so it can safely be included without depleting the battery energy. A voltage detector IC from Panasonic (Microchip also makes similar devices) is used to monitor the battery voltage. The device’s open drain output swings low, when the battery voltage is below 2.4 to 2.5 volts. This action turns on the two transistor oscillator circuit, which drives the LED with short current pulses lasting only 2ms.

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Bass and Treble Controller Audio Equalizer Circuit

An audio equalizer circuit is used to adjust the frequency response of an audio signal. This is a simple equalizer circuit  for controlling the bass and treble (tone) of an audio amplifier. For use this equalizer circuit in amplifier, equalizers output should be given in the input of amplifier. So that the main input  audio signal’s bass and treble could be controllable before the amplify section.

Circuit Diagram of Bass & Treble Controller- Audio Equalizer:

Fig: Audio equalizer circuit for Bass, Treble control

As shown here the bass and treble controller circuit  has two variable resistor(VR1 & VR2) to control  the bass and treble. VR1 for Bass Control and VR2 for Treble Control.

This Bass and Treble controller circuit needed a  12Volt power supply. I would have designed it  in that way because 12V is used in most of the audio amplifier circuit.  and since equalizer circuit is used with audio amplifier, so there no extra power supply will required for this Equalizer.  This audio equalizer circuit is very easy to build and has a very good quality.

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Jogging Timer

3V Battery powered, Beeps after a fixed minutes delay

This circuit was developed since a number of visitors of this website requested a timer capable of emitting a beep after one, two, three minutes and so on, for jogging purposes. As shown in the circuit diagram, SW1 is a 1 pole 9 ways Rotary Switch. Setting the switch in position 1, the Piezo sounder emits three short beeps every minute. In position 2 the same thing happens after a 2 minutes delay, and so on, reaching a maximum interval of 9 minutes in position 9.

Circuit diagram:

Parts:

R1_____________47K 1/4W Resistor
R2_____________10M 1/4W Resistor
R3______________1M 1/4W Resistor
R4_____________12K 1/4W Resistor (see notes)
C1,C3__________10µF 25V Electrolytic Capacitors
C2____________100nF 63V Polyester Capacitor
D1___________1N4148 75V 150mA Diode
IC1____________4093 Quad 2 input Schmitt NAND Gate IC
IC2____________4060 14 stage ripple counter and oscillator IC
IC3____________4017 Decade counter with 10 decoded outputs IC
Q1____________BC337 45V 800mA NPN Transistor
SW1___________1 pole 9 ways Rotary Switch (see notes)
SW2___________SPST Slider Switch
BZ1___________Piezo sounder (incorporating 3KHz oscillator)
B1____________3V Battery (two 1.5V AA or AAA cells in series etc.)

Notes:

1. Needing only one time set, rotary switch can be replaced by an hard-wired link.
2. A DIP-Switch can be used in place of the rotary type. Please pay attention to use only one switch at a time, or the device could be damaged.
3. Varying R4 from 10K to 15K you can obtain more or less than three short beeps after the preset time delay.
4. To obtain a one-second beep only, after the preset time delay, disconnect pin 9 of IC1C from pin 9 of IC2 and connect it to pin 8 of IC1C.

Source: www.RedCircuits.com

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Bipolar Power supply for Battery Instruments Circuits Diagram

Bipolar Power supply for Battery Instruments Circuits Diagram. To generate regulated ± 5-V supplies from a pair of dry batteries, the circuit of Fig. 1 is commonly used. In order to give protection from inadvertent reverse connection of a battery, a diode in series with each battery would produce an unacceptable voltage drop. The more effective approach is to fit diodes Dl and D2 as shown in Fig. 2, in parallel with each battery. 

When the supply is switched off, there is the risk of a reverse bias being applied across the regulators, if there is significant inductance or capacitance in the load circuit.Diodes across the regulators prevent damage. When the power supply is switched on, the two switches do not act in unison. There is a probability that one or the other regulators will be latched hard off by the other. To prevent this, D3 and D4 are Zener diodes so that ± 5-V rails are pulled up by the batteries until the regulators establish the correct levels.

Bipolar Power supply for Battery Instruments Circuits Diagram

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DC or AC Voltage Indicator

Detects 1.8 to 230 Volts DC or AC, Minimum parts counting

This circuit is not a novelty, but it proved so useful, simple and cheap that it is worth building. When the positive (Red) probe is connected to a DC positive voltage and the Black probe to the negative, the Red LED will illuminate. Reversing polarities the Green LED will illuminate. Connecting the probes to an AC source both LEDs will go on.

The bulb limits the LEDs current to 40mA @ 220V AC and its filament starts illuminating from about 30V, shining more brightly as voltage increases. Therefore, due to the bulb filament behavior, any voltage in the 1.8 to 230V range can be detected without changing component values.

Circuit diagram:

DC or AC Voltage Indicator Circuit Diagram

Parts:

P1 = Red Probe
P2 = Black Probe
D1 = 5 or 3mm. Red LED
D2 = 5 or 3mm. Green LED
LP = 1220V 6W Filament Lamp Bulb

Note:

• A two colors LED (Red and Green) can be used in place of D1 & D2.

Source: Red Free Circuit Design

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Laser Power Supply

If you have ever worked with lasers, you know how fun and interesting it can be, you also know how expensive it can be. The high voltage power supplies for the laser tubes are often more expensive then the tubes themselves. This supply can be built with common parts, most of which you probably already have in your junk box. The secret is the transformer used. It is a common 9V 1A unit, connected backwards for step up.

Parts

Part           Total Qty. Description            R1    1 10 Ohm 10W Or Greater Resistor R2    1 Ballast Resistor, See "Notes" D1, D2, D3    3 1N4007 Silicon Diode C1, C2, C3    3 0.1 uF 2000V Capacitor T1    1 9V 1A Transformer S1    1 115V 2A SPST Switch MISC    1 Case, Wire, Binding Posts (for output), Line Cord Notes T1 is an ordinary 9V 1A transformer connected backwards for step up. R1 MUST be installed on a LARGE heatsink. A good heatsink is the metal case the supply is built in. R2 Protects the laser tube from excess current. It should be soldered directly to the anode terminal on the tube. To find R2, start with a 500K 10W resistor and work down until the tube lights and remains stable. If you have trouble with the tube not starting easily, use a longer anode lead that is wrapped around the tube. Depending on the transformer you use, the circuit may or may not work. I cannot guarantee the operation of this circuit. Build at your own risk. Some transformers contain very few secondary windings which will quickly saturate the core and basically act like a direct short. The more secondary windings (that is, primary in this circuit) the better.

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Automatic Emergency Light

This is the simple circuit of automatic emergency light. It is called dark dependent circuit. A 555 timer IC and LDR is used for this configuration. When light fall on the LDR, its resistance is decrease and in dark position its resistance is going high. Using these characteristics of LDR, automatic emergency light is made.

Automatic Emergency Light Circuit diagram:

LDR is called Light Dependent Resistor. Its resistance is inversely proportional to the falling light on its surface. In dark, its resistance is approximately 7k to 10k. When light fall on its surface, its resistance is decrease to less than 1k. In the circuit, a voltage divider arrangement circuit is used here with LDR and 10K variable resistor.

When light fall on the surface of LDR, the resistance decrease to 1k. So the voltage of the timer pin-6 is greater than 2/3 of +Vcc. For this reason the output pin-3 goes low. The base voltage of transistor BC547 is less than 0.75 volt. The transistor is OFF state. So the light is OFF. In dark position the LDR resistance increase is high so the voltage of the trigger pin-2 decrease to less than 1/3 of +Vcc. The output pin-3 goes high so the base voltage of the transistor BC547 is greater than 0.75 volt. The transistor is ON state. So the light is ON and it emits light.

Source: http://www.ecircuitslab.com/2012/06/simple-automatic-emergency-light.html

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LM317 VARIABLE POWER SUPPLY Circuit Diagram

A truly timeless circuit. LM317 is a versatile and highly efficient 1.2-37V voltage regulator that can provide up to 1.5A of current with a large heat sink. Its ideal for just about any application. This was my first workbench power supply and I still use it.

 LM317 VARIABLE POWER SUPPLY Circuit Diagram

Since LM317 is protected against short-circuit, no fuse is necessary. Thanks to automatic thermal shutdown, it will turn off if heating excessively. All in all, a very powerful (and affordable!) package, indeed.

Although LM317 is capable of delivering up to 37V, the circuit pictured here is limited to 25V for the sake of safety and simplicity. Any higher output voltage would require additional components and a larger heat sink.
Make sure that the input voltage is at least a couple of Volts higher than the desired output. Its ok to use a trimmer if youre building a fixed-voltage supply.

Possible uses:
Variable workbench power supply, fixed-voltage supply... Just about any possible application when no more than 1.5A is necessary.

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Precision Headphone Amplifier

Designs for good-quality headphone amplifiers abound, but this one has a few special features that make it stand out from the crowd. We start with a reasonably conventional input stage in the form of a differential amplifier constructed from dual FET T2/T3. A particular point here is that in the drain of T3, where the amplified signal appears, we do not have a conventional current source or a simple resistor. T1 does indeed form a current source, but the signal is coupled out to the base of T5 not from the drain of T3 but from the source of T1. Notwithstanding the action of the current source this is a low impedance point for AC signals in the differential amplifier.

Precision Headphone Amplifier Circuit Diagram

Measurements show that this trick by itself results in a reduction in harmonic distortion to considerably less than –80 dB (much less than 0.01 %) at 1 kHz. T5 is connected as an emitter follower and provides a low impedance drive to the gate of T6: the gate capacitance of HEXFETs is far from negligible. IC1, a volt-age regulator configured as a current sink, is in the load of T6. The quiescent current of 62 mA (determined by R11) is suitable for  an output power of 60 mWeff into an impedance of 32 Ω, a value typical of high-quality headphones, which provides plenty of volume.

Using higher-impedance headphones, say of 300 Ω, considerably more than 100 mW can be achieved. The gain is set to a useful 21 dB (a factor of 11) by the negative feedback circuit involving R10 and R8. It is not straightforward to change the gain because of the single-sided supply: this voltage divider also affects the operating point of the amplifier. The advantage is that excellent audio quality can be achieved even using a simple unregulated mains supply.  Given the relatively low power output the power supply is considerably overspecified. Noise and hum thus remain more than 90 dB below the signal (less than 0.003 %), and the supply can also power two amplifiers for stereo operation.

The bandwidth achievable with this design is from 5 Hz to 300 kHz into 300 Ω, with an output voltage of 10 Vpp. The damping factor is greater than 800 between 100 Hz and 10 kHz. A couple of further things to note: some-what better DC stability can be achieved by replacing D1 and D2 by low-current red LEDs (connected with the right polarity!). R12 prevents a click from the discharge of C6 when headphones are plugged in after power is applied. T6 and IC1 dissipate about 1.2 W of power each as heat, and so cooling is needed. For low impedance headphones the current through IC1 should be increased. To deliver 100 mW into 8 Ω, around 160 mA is required, and R11 will need to be 7.8 Ω (use two 15 Ω resistors in parallel).

To keep heat dissipation to a reasonable level, it is recommended to reduce the power supply volt-age to around 18 V (using a transformer with two 6 V secondaries). This also means an adjustment to the operating point of the amplifier: we will need about 9V between the positive end of C6 and ground. R4 should be changed to 100 Ω, and R8 to 680 Ω. The gain will now be approximately 6 (15 dB). The final dot on the ‘i’ is to increase C7 by connecting another 4700 µF electrolytic in parallel with it, since an 8 Ω load will draw higher currents.

Source:   http://www.ecircuitslab.com/2012/02/precision-headphone-amplifier.html

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Simple Ac To Dc Converter Circuit Diagram

This is simple Ac To Dc converter circuit diagram. By coupling two back-to-back diodes in series with an ac power circuit, a voltage of about 1.4 Vpp can be obtained. This voltage is useful for exciting the primary coil of a small transformer. The voltage induced in the secondary coil can then be rectified and used to power solid-state control circuits. The forward-voltage drop of the diodes is inherently constant and stable over a wide range of ac-circuit power variations. 

The resulting voltage developed across the transformer windings is also free from variation that might be caused by changes in the circuit`s current or voltage. In the circuit, a lamp (LMP-1) is connected to the primary ac input line (Ll and L2) through a pair of inverse-parallel-connected power diodes (Dl and D2). As power flows to the lamp, a drop of about 0.7 V is alternatively developed across each of the diodes. 

This voltage feeds the primary of a small transformer (Tl). T1 can be a small 8- to 500- transistor radio output, etc. This will deliver about 11 Vpp across its secondary winding. LMP1 can be a small 120-V lamp of 5 to 25 W, etc.

Ac To Dc Converter Circuit Diagram

Simple Ac To Dc Converter Circuit Diagram

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Atv Jr Transmitter 440Mhz Circuit Diagram

This low-power video transmitter is useful for R/C applications, surveillance, or amateur radio applications. Seven transistors are used in a crystal oscillator-multiplier RF power amplifier chain, and a high-level video modulator. A 9- to 14-Vdc supply is required. Output is 0.4 to 1.2 W, depending on supply voltage. 

Atv Jr Transmitter 440Mhz Circuit Diagram

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Build a 2M 6M Transverter Circuit Diagram

Using the bilateral properties of a balanced mixer this transvertcr will produce 6-m output with 2-m inputs. Y1 is a 90-MHz crystal. Note that the input on 2 m is 143 to 144 MHz for 53 to 54-MHz output. This avoids possibility of extraneous 2-m reception during receive periods. If your radio will not transmit below 144 MHz, then use a 93- or 94-MHz crystal frequency.

2M 6M Transverter Circuit Diagram

Build a 2M 6M Transverter Circuit Diagram

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Fixed Voltage Power Supply

The fixed voltage power supply is useful in applications where an adjustable output is not required. This supply is simple, but very flexable as the voltage it outputs is dependant only on the regulator and transformer you choose. The maximum output current is 1.5A.

Fixed Voltage Power Supply Circuits diagram :

 

Parts :

Part    Total     Description

C1           1       2200uF 35V Electrolytic Capacitor

C2, C4     2       0.1uF Ceramic Disc Capacitor

C3           3       10uF 35V Electrolytic Capacitor

D1, D2    1        1N4007 Silicon Diode

BR1        1        2A 30V Bridge Rectifier

U1          1        Regulator (See Notes)

T1          1        Transformer (See Notes)

S1          1        SPST 2 Amp Switch

F1          1        2A 250V Fuse and Holder 

Misc      1        Heatsink For U1, Line Cord, Case, Wire

 

Notes :

1. Since this project operates from 120 (or 220, or 240, etc.) volts AC, it MUST be built inside a case.
2. U1 will reauire a heatsink.
3. You will need to choose T1 and U1 to match the voltage you want. Use the table below as a reference.

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MD Catridge Preamplifier

Phonographs are gradually becoming a rarity. Most of them have had to yield to more advanced systems, such as CD players and recorders or (portable) MiniDisc player/recorders. This trend is recognized by manufacturers of audio installations, which means that the traditional phono input is missing on increasingly more systems. Hi-fi enthusiasts who want make digital versions of their existing collections of phonograph records on a CD or MD, discover that it is no longer possible to connect a phonograph to the system.

 MD Catridge Preamplifier Circuit diagram:

However, with a limited amount of circuitry, it is possible to adapt the line input of a modern amplifier or recorder so that it can handle the low-level signals generated by the magnetodynamic cartridge of a phonograph. Of course, the circuit has to provide the well-known RIAA correction that must be used with these cartridges. The preamplifier shown here performs the job using only one opamp, four resistors and four capacitors. For a stereo version, you will naturally need two of everything. Any stabilized power supply that can deliver ±15V can be used as a power source.

Source:  http://www.ecircuitslab.com/2011/06/simple-md-catridge-preamplifier.html

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12V Speed Controller Dimmer

This handy circuit can be used as a speed controller for a 12V motor rated up to 5A (continuous) or as a dimmer for a 12V halogen or standard incandescent lamp rated up to 50W. It varies the power to the load (motor or lamp) using pulse width modulation (PWM) at a pulse frequency of around 220Hz. SILICON CHIP has produced a number of DC speed controllers over the years, the most recent being our high-power 24V 40A design featured in the March & April 2008 issues. Another very popular design is our 12V/24V 20A design featured in the June 1997 issue and we have also featured a number of reversible 12V designs.

Circuit looks like:

For many applications though, most of these designs are over-kill and a much simpler circuit will suffice. Which is why we are presenting this basic design which uses a 7555 timer IC, a Mosfet and not much else. Being a simple design, it does not monitor motor back-EMF to provide improved speed regulation and nor does it have any fancy overload protection apart from a fuse. However, it is a very efficient circuit and the kit cost is quite low.

Parts layout:

Connection diagram:

There are many applications for this circuit which will all be based on 12V motors, fans or lamps. You can use it in cars, boats, and recreational vehicles, in model boats and model railways and so on. Want to control a 12V fan in a car, caravan or computer? This circuit will do it for you.

Circuit diagram:

The circuit uses a 7555 timer (IC1) to generate variable width pulses at about 210Hz. This drives Mosfet Q3 (via transistors Q1 & Q2) to control the speed of a motor or to dim an incandescent lamp.
Halogen lamps: 

 
While the circuit can dim 12V halogen lamps, we should point out that dimming halogen lamps is very wasteful. In situations where you need dimmable 12V lamps, you will be much better off substituting 12V LED lamps which are now readily available in standard bayonet, miniature Edison screw (MES) and MR16 halogen bases. Not only are these LED replacement lamps much more efficient than halogen lamps, they do not get anywhere near as hot and will also last a great deal longer.

Source:  http://www.ecircuitslab.com/2012/01/12v-speed-controllerdimmer.html 

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Musical Bell

      This circuits uses very few component and gives melody sound. It uses 3 terminal IC UM66 and can be build small enough to be placed inside a greeting card and operated off a single 3V flat button cell.
    There is not much to the circuit. The UM66 is connected to its supply and its output fed to a transistor for amplification. Any common speaker can be used or a “flat” piezoelectric tweeter like the one found in alarm wrist watches. If you use the piezo, then it can be connected directly between the output pin 1 and ground pin 3 without the transistor.
    The UM66 looks like a transistor with 3 terminals. It is complete miniature tone generator with a tune. Now they come with wide variety of different tunes.
    For amplification we have used a NPN transistor which is BC548. Here BC548 makes a common emitter circuit. For limiting the base current we have used a resistance of 220 Ohms so that transistor will not get damaged by excess current.

          Circuit Diagram of Musical Bell
PROCEDURE :
1. Draw circuit diagram on ply board and make hole with compass or broader for component pin insertion.
2. Identify emitter base collector of transistor and pin no. of IC UM66
3. Solder all parts according to the circuit. You will need soldering iron, Soldering flux and flexible wire.
4. Make sure all points are well soldered according to the Circuit Diagram and no dry solders. Wrong connection of IC may heat up and get damage.
5. After loading battery power ON the circuit. Now you can check the function of the project.

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500W Low Cost 12V to 220V Inverter

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

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. 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.

Source :  http://www.ecircuitslab.com/2011/08/500w-low-cost-12v-to-220v-inverter.html

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Set Reset Flip Flop

This is an example of a set/reset flip flop using discrete components. When power is applied, only one of the transistors will conduct causing the other to remain off. The conducting transistor can be turned off by grounding its base through the push button which causes the collector voltage to rise and turn on the opposite transistor.

Set - Reset Flip Flop Circuit Diagram

• Source
• Bowdens Hobby Circuits

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Voltage Inverter Using Switch Mode Regulator

This circuit uses a step-up switch-mode regulator, which is usually used to produce a positive supply, to generate a regulated negative output voltage. The device used here is the MIC4680 from Micrel (www.micrel.com), but the idea would of course work with similar regulators from other manufacturers. Because of coil L1, which performs the voltage conversion by the intermediate storage of energy in the form of a magnetic field, the output is effectively isolated from the input. We can therefore connect the right-hand side of L1 to ground rather than to the positive output without causing a large current to flow. Then we connect the ground pin of the regulator IC and all the components connected to it as the negative voltage output, isolated from ground.

The components on the output side of the regulator are connected as usual: flywheel diode D1, coil L1 and the voltage divider formed by R1 and R2. These last two components set the output voltage, according to a formula given in the data sheet. Example component values for the MIC4680 used here are given in the table. The input voltage should lie within the permitted range for the regulator used, and must in any case be at least as great in magnitude as the desired output voltage (here +5 V or +12 V), so that the step-down regulation technique can wor.

It is important to take care when building this circuit to mount the regulator using an insulator, since generally the GND pin of the device is connected to the heatsink tab. Also, the ON/OFF control input cannot be driven using a normal logic signal, since the regulator’s ground reference is the output voltage rather than ground itself. If the ON/OFF function is required, a level shifter or optocoupler must be used.

Source: http://www.ecircuitslab.com/2011/06/voltage-inverter-using-switch-mode.html 

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Simple 6V lamp Flasher Circuit Diagram

This is a simple lamp flasher circuit diagram.Here you  can use 6V lamp.I have added this for my bike.oh it is great at night I have used blue color bulb.

Note 

# Dont supply over 6V for this circuit 
# Build this circuit on a PCB

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Voltage Converter Circuit Diagram

Teledyne Semiconductor`s Type TSC9402 is a versatile IC. Not only can it convert voltage into frequency, but also frequency into voltage. It is thus eminently suitable for use in an add-on unit for measuring frequencies with a multimeter. Only a few additional components are required for this.. Just one calibration point sets the center of the measuring range (or of that part of the range that is used most frequently). 

The frequency-proportional direct voltage at the output (pin 12—amp out) contains interference pulses at levels up to 0.7 V. If these have an adverse effect on the multimeter, they can be suppressed with the aid of a simple RC network. 

The output voltage, U0, is calculated by: tfo=C/rei(Ci + 12 pF) R2fm Because the internal capacitance often has a greater value than the 12 pF taken here, the formula does not yield an absolute value. The circuit has a frequency range of dc to 10 kHz. At 10 kHz, the formula gives a value of 3.4 V. The circuit draws a current of not more than 1 mA.

Voltage Converter Circuit Diagram

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230V Led Flasher Circuit using DIAC

This is a very simple LED flasher circuit diagram that is powered from AC 230V mains. This Flasher can be used as a power indicator for the AC 230V mains supply. This circuit is made with few numbers of parts namely, a LED, two Resistors, one Capacitor, one Diode and one DIAC.  The DIAC act the main role to flashing the LED. DIAC is a bidirectional device. It conducts current only after its breakover voltage has been reached its threshold. Most DIACs break-over voltage is around 30 V.

230V Mains Power Indicator LED Flasher Circuit Diagram

Fig: Circuit Diagram of 230V Led Flasher

When mains is connect to the circuit, the Capacitor(C1) starts charging through Diode(D1) and Resistor(R1). When the voltage on the capacitor reached the DIAC’s threshold voltage, the DIAC get turn on. And LED gets Lights(flash). At the same time Capacitor(C1) goes discharges and breakover voltage of DIAC also decrease and LED turns OFF. The on off time of the LED depends on the value of Capacitor(C1)  and Resistor(R1).

Note that the flashing time of the LED shown in the animating figure is not the exact timing of ON/OFF.

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10W Audio Amplifier With Bass Boost

High Quality, very simple design, No preamplifier required

This design is based on the 18 Watt Audio Amplifier, and was developed mainly to satisfy the requests of correspondents unable to locate the TLE2141C chip. It uses the widespread NE5532 Dual IC but, obviously, its power output will be comprised in the 9.5 - 11.5W range, as the supply rails cannot exceed ±18V. As amplifiers of this kind are frequently used to drive small loudspeaker cabinets, the bass frequency range is rather sacrificed. Therefore a bass-boost control was inserted in the feedback loop of the amplifier, in order to overcome this problem without quality losses. The bass lift curve can reach a maximum of +16.4dB @ 50Hz. In any case, even when the bass control is rotated fully counterclockwise, the amplifier frequency response shows a gentle raising curve: +0.8dB @ 400Hz, +4.7dB @ 100Hz and +6dB @ 50Hz (referred to 1KHz).

 10W Bass Boost Amplifier Circuit diagram:

Parts:

P1_________________22K Log.Potentiometer (Dual-gang for stereo)
P2_________________100K Log.Potentiometer (Dual-gang for stereo)
R1_________________820R 1/4W Resistor
R2,R4,R8___________4K7 1/4W Resistors
R3_________________500R 1/2W Trimmer Cermet
R5_________________82K 1/4W Resistor
R6,R7______________47K 1/4W Resistors
R9_________________10R 1/2W Resistor
R10________________R22 4W Resistor (wirewound)
C1,C8______________470nF 63V Polyester Capacitor
C2,C5______________100µF 25V Electrolytic Capacitors
C3,C4______________470µF 25V Electrolytic Capacitors
C6_________________47pF 63V Ceramic or Polystyrene Capacitor
C7_________________10nF 63V Polyester Capacitor
C9_________________100nF 63V Polyester Capacitor
D1_________________1N4148 75V 150mA Diode
IC1_________________NE5532 Low noise Dual Op-amp
Q1_________________BC547B 45V 100mA NPN Transistor
Q2_________________BC557B 45V 100mA PNP Transistor
Q3_________________TIP42A 60V 6A PNP Transistor
Q4_________________TIP41A 60V 6A NPN Transistor
J1__________________RCA audio input socket

Power Supply Circuit diagram:

 

Power supply parts:

R11______________1K5 1/4W Resistor
C10,C11__________4700µF 25V Electrolytic Capacitors
D2_______________100V 4A Diode bridge
D3_______________5mm. Red LED
T1_______________220V Primary, 12 + 12V Secondary 24-30VA Mains transformer
PL1______________Male Mains plug
SW1______________SPST Mains switch

Notes:

• Can be directly connected to CD players, tuners and tape recorders.
• Schematic shows left channel only, but C3, C4, IC1 and the power supply are common to both channels.
• Numbers in parentheses show IC1 right channel pin connections.
• A log type for P2 will ensure a more linear regulation of bass-boost.
• Do not exceed 18 + 18V supply.
• Q3 and Q4 must be mounted on heatsink.
• D1 must be in thermal contact with Q1.
• Quiescent current (best measured with an Avo-meter in series with Q3 Emitter) is not critical.
• Set the volume control to the minimum and R3 to its minimum resistance.
• Power-on the circuit and adjust R3 to read a current drawing of about 20 to 25mA.
• Wait about 15 minutes, watch if the current is varying and readjust if necessary.
• A correct grounding is very important to eliminate hum and ground loops. Connect to the same point the ground sides of J1, P1, C2, C3 &C4. Connect C9 to the output ground.
• Then connect separately the input and output grounds to the power supply ground.

Technical data:

Output power:
10 Watt RMS into 8 Ohm (1KHz sinewave)
Sensitivity:
115 to 180mV input for 10W output (depending on P2 control position)
Frequency response:
See Comments above
Total harmonic distortion @ 1KHz:
0.1W 0.009% 1W 0.004% 10W 0.005%
Total harmonic distortion @ 100Hz:
0.1W 0.009% 1W 0.007% 10W 0.012%
Total harmonic distortion @ 10KHz:
0.1W 0.056% 1W 0.01% 10W 0.018%
Total harmonic distortion @ 100Hz and full boost:
1W 0.015% 10W 0.03%
Max. bass-boost referred to 1KHz:
400Hz = +5dB; 200Hz = +7.3dB; 100Hz = +12dB; 50Hz = +16.4dB; 30Hz = +13.3dB
Unconditionally stable on capacitive loads

Source :  http://www.ecircuitslab.com/2011/05/10w-audio-amplifier-with-bass-boost.html

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Car Boot Light Warning

On many cars, the boot light will not go out until the lid is properly closed. It is all too easy when unloading the car, to leave the lid ajar. If you are unlucky and the car remains unused for some time, the next time you try to start it, the lamp will have drained the battery and you will no doubt utter a few appropriate words. The circuit described here will give a warning of just such a situation.

A mercury tilt switch is mounted in the boot so that as the lid is closed, its contacts close before the lid is completely shut. The supply for the circuit comes from the switched 12 V to the boot lamp and through the mercury switch. When the lid is properly closed, the boot lamp will go out and the supply to the circuit will go to zero. If however the lid is left ajar, the lamp will be on and the mercury switch will close the circuit.

Car Boot  Light  Warning Circuit diagram :

After 5 seconds, the alarm will start to sound, and unless the lid is shut, it will continue for 1 minute to remind you to close the boot properly. The 1-minute operating period will ensure that the alarm does not sound continuously if you are, for example, transporting bulky items and the boot will not fully close. The circuit consists of a dual CMOS timer type 7556 (the bipolar 556 version is unsuitable for this application). When power is applied to the circuit (i.e. the boot lid is ajar) tantalum capacitors C1 and C2 will ensure that the outputs of the timers are high. After approximately 5 seconds, when the voltage across C2 rises to 2/3 of the supply voltage, timer IC1b will be triggered and its output will go low thereby causing the alarm to sound.

Meanwhile the voltage across C1 is rising much more slowly and after approximately 1 minute, it will have reached 2/3 of the supply voltage. IC1a will now trigger and this will reset IC1b. The alarm will be turned off. IC1a will remain in this state until the boot lid is either closed or opened wider at which point C1 and C2 will be discharged through R6 and the circuit will be ready to start again. To calculate the period of the timers use the formula: t = 1.1RC Please note that the capacitor type used in the circuit should be tantalum or electrolytic with a solid electrolyte. The buzzer must be a type suitable for use at D.C. (i.e. one with a built in driver).

Source : www.ecircuitslab.com/2011/.../car-boot-lamp-warning-icm7556.html

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Simple 1 5V Supply For Zn416E Circuits Diagram

This regulator can be used with a +6-V source to supply ZN416E low-voltage TRF radio-receiver IC the necessary +1.5 V. R3 sets output voltage.


Simple +1.5V Supply For Zn416E Circuits Diagram

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Photodiode Alarm

This Photodiode based Alarm can be used to give a warning alarm when someone passes through a protected area. The circuit is kept standby through a laser beam or IR beam focused on to the Photodiode. When the beam path breaks, alarm will be triggered. The circuit uses a PN Photodiode in the reverse bias mode to detect light intensity. In the presence of Laser / IR rays, the Photodiode conducts and provides base bias to T1.

The NPN transistor T1 conducts and takes the reset pin 4 of IC1 to ground potential. IC1 is wired as an Astable oscillator using the components R3, VR1 and C3. The Astable operates only when its resent pin becomes high. When the Laser / IR beam breaks, current thorough the Photodiode ceases and T1 turns off. The collector voltage of T1 then goes high and enables IC1. The output pulses from IC1 drives the speaker and alarm tone will be generated.

Photo-Diode Alarm Circuit

IR Transmitter Circuit

A simple IR transmitter circuit is given which uses Continuous IR rays. The transmitter can emit IR rays up to 5 meters if the IR LEDs are enclosed in black tubes.

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Simple split power supply circuit Diagram

This circuit utilizes the quasi-complementary output stage of the popular LM380 audio power IC. The device is internally biased so that with no input the output is held midway between the supply rails Rl, which should be initially set to mid-travel, is used to nullify any inbalance in the output. 

Regulation of Vout depends upon the circuit feeding the LM380, but positive and negative outputs will track accurately irrespective of input regulation and unbalanced loads. 

The free-air dissipation is a little over 1 watt, and so extra cooling: may be required. The device is fully protected and will go into thermal shutdown if its rated dissipation is exceeded. Current limiting occurs if the output current exceeds 1 A. The input voltage should not exceed 20 V.

Simple split power supply circuit Diagram

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Dual Output dc dc Converter Circuit Diagram

The Dual Output dc-dc Converter Circuit Diagram buck-boost configuration the MAX634 is well suited for dual output dc-dc converters. Only a second winding on the inductor is needed. Typically, this second winding is bifilar-primary and secondary are wound simultaneously using two wires in parallel. 

The inductor core is usually a toroid or a pot core. The negative output voltage is fully regulated by the MAX634. The positive voltage is semi-regulated, and will vary slightly with load changes on either the positive or negative outputs.

Dual Output dc-dc Converter Circuit Diagram

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Build a Long Line Ir Drop Voltage Recovery Circuit Diagram

How to Build a Long Line Ir Drop Voltage Recovery Circuit Diagram? This Simple Long Line Ir Drop Voltage Recovery Circuit Diagram provides a unique solution to a common system-level power distribution problem: When the supply voltage to a remote board must traverse a long cable, the voltage at the end of the line sometimes drops to unacceptable levels. 

This + 5-V/ + 5-V converter addresses this by taking the reduced voltage at the end of the supply line and boosting it back to + 5 V. This can be especially useful in remote display devices, such as some point-of-sale (POS) terminals, where several meters of cable could separate the terminal from the readout.

Long Line Ir Drop Voltage Recovery Circuit Diagram

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200w Audio Power Amplifier

This audio amplifier circuit delivers up to 200 W of top-class quality for loudspeaker from 4 to 16 ohm. Operating voltage is between 24 and 36 V, max 5 A. The frequency response is from 20 to 20000 Hz.  Please take special care that the transistors and the IC’s have been fixed firmly and solely one or two separated cooling elements with sufficient dimensions for this purpose (thermal resistance < 1K/W).

200W Audio Power Amplifier Circuit Diagram :


Doing so it is necessary to mount the transistors and the IC’s insulated (with mica washes and plastic nipple). Please make sure before first operation that the transistors and the IC’s really do not have any electrical connection towards the cooling plate! The transistors have to be placed plane and firmly onto the cooling element! It is of extraordinary importance with this high-power amplifier that there is a considerable heat dissipation. The already mounted cooling element should be situated in a well ventilated case.
The PSU should be sufficiently powerful, power consumption of the amplifier may increase up to 5A. In case of using an unstabilised power supply. It is advisable to place a transformer of max 28V.
The amplifier will the show approx. 120W at a 4-Ohm loudspeaker, for it no-load voltage of the power supply will not be to high. If it is desired to use complete power, it is necessary to place a stabilised power supply with approx. 36V 5A. No-load voltage should not pass over 44V!
The cables leading the current supply and to the loudspeakers should have at least a cross section of min. 1.5 mm^2. The connected loudspeaker have to be equiped according to the high output power and should not have a lower impedance as 4 Ohm! With lower connection impedance and short circuit within the loudspeaker wiring, the transistors will be destructed.
The amplifier has an input sensitivity of approx. 500 … 800 mV. Therefore, it is possibile to connect directly at the amplifier tape decks, tuners, etc. In case there are connected signal sources with lower output voltage, it is necessary to pre-connect a preamplifier. Then it will alse be posible to connect microphones, etc.

200W audio amplifier PCB :

Parts List :

IC1, IC2 = 2 IC’s TDA2030
T1, T3 = 2 transistors KT818 or BD708
T2, T4 = 2 transistors KT819 or BD705
C1, C2, C3, C4, C7 = 5 capacitors 150 nF
C5 = 1 elca 10uF 63V
C8 – 1 capacitor 1.8 nF
R1, R7, R9 = 3 resistances 100K
R2, R3, R10, R11 = 4 resistances 2.2 Ohm
R4, R5 = 2 res. 2K
R6, R8 = 2 res. 1 Ohm
R12, R13 = 2 res. 2 res. 3.3K
D1…D4 = 1N4001, 1N4002, 1N4003
1 PCB board approx 56×51 mm

Source :http://www.ecircuitslab.com/2012/08/200w-audio-power-amplifier.html

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Laser Level Detector

Rotating laser levels, which are very handy  for setting objects in a room or garden at the  same height, are available at prices of a few  dozen pounds. At relatively large distances  and for outdoor use, the light from the rotating laser beam is often not easy to see, and  the laser beam detector described here can  be useful in such situations. The detector  works well at distances up to 50 metres (150  feet) and consists entirely of standard components. The detector is housed in a plastic case  that can be fixed to an object (such as a post  or a beam). It has three LEDs and a beeper that  indicate whether the object should be raised  or lowered.

LEDs with a transparent package and integrated lens (round surface) are used as sensors. The top and bottom detection zones  each have five LEDs and two opamps (IC1a &  IC1b or IC1c & IC1d), which drive the ‘Move  Up’ and ‘Move Down’ indicator LEDs. The middle sensor LED drives the ‘OK’ indicator LED  via two opamps (IC2a & IC2b).  The rising edges of the opamp output signals  trigger three separate monostable multivibrators (type CD4047). If desired, the circuit  shown inside the dashed outline (one gate of a  CD4044 quad RS latch) can be used in place of  each of the monostable multivibrators. In this  case the output signal has the opposite polar-ity, so the BS170 N-channel MOSFET must be  replaced by a P-channel type.

The monostable time of the middle retriggerable MMV should be longer than the rotation period of the laser (e.g. with a 2 rpm laser  it should be longer than 500 ms) so that the  beeper will emit a continuous tone. Most  rotating laser levels have variable speed, so  this can also be achieved by adjusting the peed if necessary. The monostable times of  the upper and lower MMVs are dimensioned  to generate clearly distinguishable short and  long beeps, respectively. The three MOSFETs  (T1, T2 and T3) are configured as a wired-OR  gate to drive the shared beeper. The fourth  MOSFET (T4) drives the ‘OK’ LED.

The circuit can be housed in an enclosure  together with three penlight cells.

Source: http://www.ecircuitslab.com/2012/05/laser-level-detector.html

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Stepper Motor Circuit with IC 4027

This stepper controller circuit shown here can used to control the unipolar stepper motor,which has 4 coils . The stepper controller circuit can drive for a motor current of up to about 500 mAmp/Winding by suitable heat sinks for the SL-100. directsinks In higher currents power transistors seem 2N3055 can be used as darlington pair along with SL-100. All diodes are used to protect back current the transistor from transients.

Stepper Motor Circuit with IC 4027 Circuit diagram :

Remark. 

• You may be able to substitute any standard (2N3055) power transistor for Q1-Q4 or get IC type UL to modify for transistor.
• Every time in move the motor put signal the STEP line is pulsed, the motor moves one step.
• Switch S1 for changes the motors direction

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Regulator current Source Circuit Diagram

The circuit powers the load via the regulator`s input instead of its output. Because the regulator`s output sees constant dummy load R1, it tries to consume a constant amount of current, no matter what the voltage across the actual load really is. Hence, the regulator`s input serves as a constant-current source for the actual load. 

Power the circuit with any one of the commonly available ± 15 or ±12 V supplies. The voltage dropped across the regulator and dummy load decreased the total compliance voltage of the~circuit. You set the load`s current with Rl. The current equals 1.25 A/`J x Rl.

Regulator current Source Circuit Diagram

Regulator current Source Circuit Diagram

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