Heat Detector Alarm using UM3561 Circuit Diagram

A very simple heat detector alarm electronic project can be designed using the UM3561 sound generator circuit and some other common electronic parts . This heat detector electronic circuit project uses a complementary pair comprising npn and pnp transistor to detect heat Collector of T1 transistor is connected to the base of the T2 transistor , while the collector of T2 transistor is connected to RL1 relay T3 and T4 transistors connected in darlington configuration are used to amplify the audio signal from the UM3561 ic.

When the temperature close to the T1 transistor is hot , the resistance to the emitter –collector goes low and it starts conducting . In same time T2 transistor conducts , because its base is connected to the collector of T1 transistor and the RL1 relay energized and switches on the siren which produce a fire engine alarm sound. This electronic circuit project must be powered from a 6 volts DC power supply , but the UM3561 IC is powered using a 3 volt zener diode , because the alarm sound require a 3 volts dc power supply. The relay used in this project must be a 6 volt / 100 ohms relay and the speaker must have a 8 ohms load and 1 watt power.

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Headphone Amplifier Using Discrete Components

An amplifier to drive low to medium impedance headphones built using discrete components.

Both halves of the circuit are identical. Both inputs have a dc path to ground via the input 47k control which should be a dual log type potentiometer. The balance control is a single 47k linear potentiometer, which at center adjustment prevents even attenuation to both left and right input signals. If the balance control is moved towards the left side, the left input track has less resistance than the right track and the left channel is reduced more than the right side and vice versa. The preceding 10k resitors ensure that neither input can be "shorted" to earth.

Circuit diagram:

Headphone Amplifier Circuit Diagram

Amplification of the audio signal is provided by a single stage common emitter amplifier and then via a direct coupled emitter follower. Overall gain is less than 10 but the final emitter follower stage will directly drive 8 ohm headphones. Higher impedance headphones will work equally well. Note the final 2k2 resistor at each output. This removes the dc potential from the 2200u coupling capacitors and prevents any "thump" being heard when headphones are plugged in. The circuit is self biasing and designed to work with any power supply from 6 to 20 Volts DC

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Easy Balanced Output Board For The Stereo DAC Circuit

Easy Balanced Output Board For The Stereo DAC Circuit. This add-on board is designed to provide a pair of balanced audio outputs for the High-Quality Stereo DAC (Digital to Analog Converter). Two 3-pin male XLR connectors are used for the new outputs and they can either replace or augment the existing unbalanced outputs without affecting their performance. Balanced audio is used in recording studios and on stage because of its improved noise immunity.

Picture of the project:

    

This is due to the fact that the signal is sent differentially (ie, as two signals 180° out of phase) and then converted to a single-ended voltage signal at the far end. If any noise is picked up in the cable, it affects the two out-of-phase signals equally so that when the signals are subsequently subtracted, most of the noise is eliminated.

Parts layout:

In addition, the DAC’s performance at the balanced outputs generally exceeds that of the unbalanced outputs, although only by a small margin. The signal-to-noise ratio, frequency response and channel separation are all better, although we measured a tiny bit more distortion from the balanced outputs. However, both levels are so low as to be almost negligible.

Circuit diagram:

Comparison chart:

Source : www.circuitsproject.com

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THE LEACH SUPERAMP 270 W

This amplifier is the monophonic 270 watt Double barreled Amplifier. For the original article, I specified plus and minus 85 V dc power supply voltages. The voltage can be increased to about 93 V to obtain a power rating of 300 W. The amplifier can be built either as a stereophonic or a monoponic unit. My original amps were mono units because the heat sinks, transformer, and filter caps that I used were too large for a stereo amp. The circuit described on this page is a modification of the original Double Barreled Amplifier. The circuit has been simplified somewhat. The circuit board layout is smaller and much more compact. The driver transistors now mount on the circuit board instead of on external heat sinks. And the circuit has the feedforward compensation that I describe for the Low TIM Amplifier. If you build this amplifier, you must keep the wiring between the heat sinks and the circuit boards as short as possible if you dont want oscillation problems. When you test the circuit boards before connecting the power transistors, temporarily connect a 10 ohm resistor in series with a 0.1 ufd capacitor from the loudspeaker output to the power supply ground.


The Circuit Boards
I do not have circuit boards for the Double Barrelled Amplifier. If you wish to build it, you must make your own. Two drawings show the parts layout on the board, one with circuit traces and one without. These are scaled by a factor of 1.5. The other shows the circuit traces only. All layout views are from the component side of the board. You must flip the layout for the foil traces over to obtain the solder side view. The circuit board measures 4 inches by 6 inches. To my knowledge, there are no errors in the layout. If you decide to use it, you should carefully check it for errors because I could have easily made a mistake. I do not recommend that you make the circuit boards unless you have experience in doing it. A source of materials for making your own printed circuits can be found here. I have been told that their "Press and Peel Blue" product (not the wet stuff they sell) can be used to successfully make boards with traces as narrow as 0.01 inch. The smallest traces on the amplifier layout are 0.03 inch wide. The PnP Blue product is basically a transfer medium that allows you to transfer the toner image from a laser printer directly onto bare copper clad board and then etch it in FeCl3 (ferric chloride). After you etch the board, the copper should be cleaned with steel wool, lightly coated with solder flux, and then "tinned" with a soldering iron and rosin core solder. Do not use a commercial tinning solution that you dip the board into. It is almost impossible to solder a board that is tinned with one of these products because they corrode very quickly. When you drill the board, you should use the correct size drill bit for the pads. The hole diameters I recommend are: small pads - 0.032 inch, medium pads - 0.040 inch, large pads - 0.059 inch, mounting holes - 0.125 inch. If you do not use a sharp drill bit, you can pull the pads off the board when you drill it.

Circuit Description
If you compare the Double Barreled circuit to the Low TIM circuit, you will see a lot of similarity between the two. Indeed, there is a Low TIM Amplifier embedded in the Double Barreled Amplifier. The major difference between the two is that transistors are added in series with those in the Low TIM circuit to form the Double Barreled circuit. By doing this, the voltage across the transistors is decreased so that the power supply voltage can be increased for higher output power. Basically, the circuit description for the Low TIM Amplifier also applies to the Double Barreled Amplifier. The major difference between the two is the addition of transistors Q22 through Q31. Q22 is connected as a common base stage at the output of Q12. The two transistors form a cascode stage. The base of Q22 connects to the junction of R52 and R54. These two resistors are equal and are connected as a voltage divider between the loudspeaker output and the positive rail. This forces the base voltage of Q22 to float half way between the loudspeaker output voltage and the positive power supply rail. Similarly, Q13 and Q23 form a cascode stage. R53 and R55 force the base of Q23 to float half way between the loudspeaker output voltage and the negative power supply rail. The addition of Q22 and Q23 cause the collector to emitter voltages of Q12 and Q13 to be approximately one-half of what the voltages would be without Q22 and Q23. Transistors Q24 and Q25 connect in series with the pre-driver transistors Q14 and Q15. The base of Q24 floats half way between the output voltage and the positive rail. The base of Q25 floats half way between the output voltage and the negative rail. The addition of Q24 and Q25 cause the voltages across Q14 and Q15 to be approximately one-half of what they would be without Q24 and Q25. Similarly, transistors Q26 through Q31 cause the voltages across Q16 through Q21 to be approximately one-half of what they would be without Q26 through Q31. By connecting the transistors in series in this way, the rail voltages can be increased for higher output power. The basic construction details of the Low TIM Amplifier also apply to the Double Barreled Amplifier. There are two short circuit jumper wires that must be soldered on the circuit board. These are marked with a J on the layout. In addition, you must solder a short circuit jumper in place of C6B if you use a non-polar capacitor for C6A. This is explained in the parts list for the Low TIM Amplifier. Because there are eight output transistors, two main heat sinks per channel are required. Q18, Q20, Q28, and Q30 should be mounted on one and Q19, Q21, Q29, and Q31 on the other. Resistors R61 through R64 and wires connecting the collectors of Q18 and Q20 and the collectors of Q19 and Q21 mount on the heat sinks. These connect between lugs on the transistor sockets. The four bias diodes D1 through D4 can be mounted on either heat sink. It is not necessary to divide the diodes between the two heat sinks because both heat sinks will operate at the same temperature. I recommend setting the voltage across Q7, i.e. the voltage between the collectors of Q22 and Q23, so that that amplifier is biased at 120 mA. This will give the same quiescent power dissipation per heat sink as in the Low TIM Amplifier.

Testing the Circuit Boards
After you solder the parts to the circuit board, it is tested using the same procedure specified for the Low TIM circuit board. First, you must solder the short circuit jumper across Q7 and you must solder the 100 ohm 1/4 W resistors from the loudspeaker output to the emitters of Q16 and Q17. If you dont have a bench power supply that puts out plus and minus 85 to 93 V dc, you can test the circuit board at a lower voltage. I would prefer test voltages of at least plus and minus 50 V dc. An option is to connect bench power supplies in series to obtain the plus and minus 85 to 93 V dc. I have routinely connected two 40 V Hewlett Packard power supplies in series with the positive and negative outputs of a Hewlett Packard 50 V dual power supply, and I have never had any problems. To protect the circuit boards, you might want to put a 100 ohm 1/4 W resistor in series with the plus and minus power supply leads for the tests. The current drawn by the circuit should be low enough so that the voltage drop across these resistors is less than 1 V if nothing is wrong on the circuit board. There are 2 ground wires from the circuit board. Both must be connected when testing the boards. I cant stress how important it is to be careful in testing a circuit board. Even simple errors can cause the loss of many expensive transistors. I always use current limited bench power supplies to test a circuit board before and after connecting the power transistors. I also bias an amplifier using current limited power supplies in place of the amplifier power supply. When I initially power up an amplifier with its own power supply, I always use a Variac variable transformer to slowly increase the ac input voltage from 0 to 120 V rms while observing the amplifier output on an oscilloscope with a sine wave input signal. If I see anything wrong on the oscilloscope, I turn the Variac to zero and try to diagnose the problem using the bench power supply. I never use a load on the amplifier for these tests.

Parts List
With the following exceptions, the parts for the Double Barreled Amplifier are the same as for the Low TIM Amplifier.
Capacitors
C10, C11 - 15 pF mica
C13, C14 - 100 uFd 100 V radial electrolytic
C21, C22 - 47 uFd 100 V radial electrolytic
C26, C27 - 270 pF mica
C28 - 0.01 uFd 250 V film
Transistors
Q1, Q2, Q5, Q7, Q9, Q10 - MPS8099 or MPSA06
Q3, Q4, Q6, Q8, Q11 - MPS8599 or MPSA56
Q23, Q24 - 2N3439
Q22, Q25 - 2N5415
Q26 - MJE15030
Q27 - MJE15031
Q28, Q30 - MJ15003
Q29, Q31 - MJ15004
Diodes
D5, D6 - 1N4934 fast recovery rectifier
D13 through D16 - 1N5250B 20 volt zener diode
Resistors
R13, R14 - 5.6 kohm 1 watt (This value is for 85 V power supplies. For other power supply voltages, the formula is on the Parts List page for the Leach Amp.)
R28, R29 - 200 ohm 1/4 watt
R30, R31 - 3.9 kohm 1 watt
R37 through R40 - 470 ohm 1/4 watt
R41 through R44 - 10 ohm 1/2 watt (changed 6/27/00)
R52 through R55 - 6.2 kohm 1 watt
R56 through R59 - 10 ohm 1/2 watt (changed 6/27/00)
R60 - 39 ohm 1/4 watt
R61 through R64 - 0.33 ohm 5 watt. These 4 resistors are mounted on the heat sinks between solder lugs on the power transistor sockets. The wires that connect the collectors of Q18 and Q20 and the collectors of Q19 and Q21 are also soldered between the lugs on the sockets. Keep all leads as short as possible and use insulation stripped from hookup wire around the bare leads of the resistors.
R65, R66 - 300 ohm 1/4 watt

Download :

• Parts Layout on Circuit Board
• Diagram showing wiring of R61 and R63 to the sockets of Q18, Q20, Q28, and Q30 in the heat sink channel. 
• Circuit Diagram 
• Circuit Board Foil Pattern 
• Part Layout with Underlying Traces

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Temperature Candle Using LED

LED based projects require a lot of skill and hence only experienced circuit designers try out these circuits. But there are also a few circuits in this genre that can be done by amateur electronic hobbyists. The temperature candle is one such circuit. Read on to know more about this.

The hardware components that are required to build this circuit are listed below:

- Microcontroller

- Temperature Sensor

- RGB LED

- PCB

The circuit design is pretty simple. The LED is made to flicker by the microcontroller and the color is based on the ambient temperature at that point. The temperature of the room can be known by observing the color of the LED.

The temperature value is obtained in degree Celsius. This value is received as a result of pressing the reset button on the PCB. This value can also be obtained by providing power to the device. Once the device is powered up, the change in temperature is indicated. The blue LED is triggered for a temperature increase of 10 degrees. The red LED is triggered for a temperature increase of a single degree.

Suppose, the ambient temperature is 23 degrees celsius, The circuit works in such a way that the blue LED is made to blink twice and the red LED is made to blink 3 times. Soon after this, an orange colored flicker is observed as the LED goes into canfle mode.

Since through hole components are used in this circuit, it is very cheap to construct and the components can be easily soldered. The circuit also contains a jack for connecting to a Microchip Pickit 3 programmer / debugger. This reduces the complexity involved in code modification and download.

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6V to 12V Converter Circuit with BD679 BC547

This is a design circuit for converter circuit. This circuit is based on transistor as controller the circuit. There are two types of transistor that is BC547 and BD679. This circuit is a simple design of converter or inverter. This is the figure of the circuit.

This inverter circuit can to 800mA of 12V power supply with a 6V. For example could you 12V Car Accessories (UK turning into a 6V?) Car. The circuit is simple, more than 75% efficiency and very helpful. By changing a few components you, you also change for different voltages.

Electronic Part List

R1, R4 2 .2 K 1/4W Resistor

R2, R3 47K 1/4W Resistor

R5 1K 1/4W Resistor

R6 15K 1/4W Resistor

R7 33K 1/4W Resistor

R8 10K 1/4W Resistor

C1, C2 0.1uF Ceramic Disc Capacitor

C3 470uF 25V electrolytic capacitor

1N914 diode D1

D2 Diode 1N4004

D3 12V 400mW Zener Diode

Q1, Q2, Q4 BC547 NPN transistor

BD679 NPN transistor Q3

L1 See Notes

Notes

1. L1 is a custom inductor wound with about 80 turns 0.5 mm magnet wire a ring around the core with an outer diameter of 40 mm.

2. Different values of D3 can be used to obtain different output voltages from 0.6V to 30V is about. Note that at higher voltages, the circuit could perform just as well and can not produce much electricity. You may need to use a larger C3 for higher voltages and / or higher currents.
3. You can use a larger value for C3, in order to achieve a better filtering.
4. The circuit requires about 2A from the 6V supply to provide the full 800mA at 12V.

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Two Colour LED Lights Bar

This circuit is a circuit run on alternating two insignia.It uses the 2-color LED with a built-participating in 3-pin single.This preference look for away the glow of every LED until the base.It turns alternating to one more color.In in the least way to the moon on the moon essential end, afterward the LED end of the first LED.Circuit consists of, nand gate ic.Two 10 Counter circuits IC, and IC JK flip washout .Company of the circuit is not speaking into 3 sets.It is a solid of gesture generators, a set of parade and control.Set the signal generator is IC1a,and IC1b quantity 4011 is a signal generator.The R2, R3, C2 determine the frequency generated.The hint is fed to a set of impressions is the figure 4011 IC2 and IC3.The 10 counter circuits to output to the LED, and Is the same, but the effort should ensue performed individual by the side of region.

Therefore, the show from pin 11 of IC 2 and tested pro D2 and D3,To pin 3 of IC4.The integrated circuit IC 4 is a JK flip slump is connected to a T flip flop.The signal input pin 3 and pin 1 is the output hint at.Which sends a signal to the Reset IC either obstruct working.IC4 on the anniversary, it want output the originally moment in time, happening contrast to pin1.IC3 progress to handiwork, IC2 stopped.
IC2 is controlled by signals from pin 1 of IC4, to IC1c.earlier to control IC2.The IC3 is connected to pins 1 through D1 to the control again

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Alpine Audio Amplifier 500 Watt RMS

Alpines Amplifier to chain is a good series of normal-grade amplifiers. They arent lofty terminate, but they value is isnt "high end" either. They are efficient and control well with vehicles with the purpose of dont exactly say a bundle of further amps free in support of powering amplifiers. I run an MRP-M500 and an MRP-F300 arrived my Honda Fit and they both supply me with capable, clean power not including taxing my cars electrical usage.

In my system, the M500 is powering a 12" subwoofer in a insignificant, sealed box. with the purpose ofs not exactly a formula meant for greatest extent deep shock, but the M500 does a major occupation pushing my subwoofer to its fullest budding. The classify-D circuitry makes the amp very efficient so with the purpose of it bidding effort well clothed in nearly all vehicles electrical systems.

The lone downside Ive found is to the EQ functions are relatively inadequate. You comprehend controls designed for hub frequency, crossover advantage, and low boost. It makes it a minute other intricate to get a smooth sound flanked by this amp and your four-channel amp. It presently takes longer than if in attendance were supplementary EQ controls. too, the low boost puts a definite crest voguish its frequency output so so as to the amplitude drops sour higher than and underneath the inside frequency. That earnings that if you like to step the greatest power output, your range is open to come to pass somewhat inadequate.

Overall, Im very glad with the M500. seeing that extended as youon the subject of not looking to power a massive, inefficient subwoofer, it be supposed to donate you a very smooth, musical sound.

MRP-M500 - Alpine Monoblock 500 Watt RMS Power Amplifier  :

Product Features

• Mono subwoofer car amplifier
• 300 watts RMS x 1 at 4 ohms (500 watts RMS x 1 at 2 ohms)
• Class D amp with MOSFET power supply
• 10-11/16"W x 2-7/16"H x 9-9/16"D

Technical Details

• Brand Name: Alpine
• Model: MRP-M500
• Faceplate Type: Detachable
• Device Type: Amplifier
• MP3 player: N
• Warranty: 1 year warranty

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How to check TV Flyback

There are actually several kinds of tools that can be used for check whether flybak damaged. But we have a simple way we have always done for ascertain whether flybak damaged or is still good, before replacing the horizontal transistor. All it takes is a light bulb with an added Exciter 100Watt cable connection along approximately 25cm.

The trick determine if flyback damaged or is still good is as follows :

1. Break up the relationship between the collector of transistor horizontal flyback-out. By (a) Open collector aspirated by means of the printed board solder, or (b) Remove the jumper cables if any, or (b) Cutting prited path.
2. Ac volt-meter pairs of horizontal transistor base with a ground out.
3. Turn on the plane a little while - there must be an ac voltage of about 1v. This is done is for ensure that the horizontal oscillator and driver are working horizontally.
4. Replace light bulb between the collector of transistor flyback horizontal (light diseri the collector).
5. Turn on the plane while alternately measured heater voltage, screen (screen VR max).
6. If no defective flyback voltage means. Usually marked with a light bulb that lights a little brighter.
7. If the flyback is usually a good heater ac voltage is approximately 1 to 2v, screen voltage around 150v. Usually marked with a light bulb that lights dimmed.
8. Measurements must be done quickly, because if the plane using circuit protectionism - protectionism will actively work then.

Defective flyback symptoms include:

• Tr horizontal collapsed immediately replaced by new
• B + voltage drops

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Phone busy pointer circuits

Phone circuits are busy pointer. A busy signal is a signal that indicates that someone is trying to call a phone number but could not be contacted because the phone if it is not involved, or because the circuits are busy, calls are impossible to solve.

On many phones, busy signals take the form of a distinctive tone, but a busy signal can also be visual, as in the case yanga phone designed for users of deafness or hearing impairment. Many people are familiar with a busy signal sounds, because significantly different from the dial tone, a tone that indicates that the phone line is open and ready to be called.

In most cases, only a busy signal indicates that the person you are calling is a call. A busy signal will also sound when the phone is turned off. In this case, the signal indicates that there are no technical obstacles to placing the call, but calls can not be completed because the phone is in use.

In some cases, you can ask the operator to enter, if you call in an emergency, in this case the operator will interrupt the call and inquire whether the subject is willing to take your call.

Have you ever use a modem or fax and someone else pick up the phone, disconnect? Phone circuits are busy these simple pointers that will end all that. Menunjukkam phone signal is being used then the red LED. When the phone is not used, the green LED lights up. It does not require external power and can be connected anywhere on the phone line, even mounted inside the phone.

Phone busy pointer circuits 

List of Components:

R1 = 3.3K 1/4 W Resistor

R2 = 33K 1/4 W Resistor

R3 = 56K 1/4 W Resistor

R4 = 22K 1/4 W Resistor

R5 = 4.7K 1/4 W Resistor

Q1, Q2 = 2N3392 NPN Transistor

BR1      = 1.5 Amp 250 PIV Bridge Rectifier

LED1   = LED red

LED2   = LED green

Others  = Wire, Containers, Telephone Cable

This circuit is very simple and easy to make on the board and installed on the phone. Try a series of telephone busy pointer

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3 Watt stereo amplifier circuit

3 Watt stereo amplifier circuitusing MAX 7910 IC. The MAX9710 a stereo audio power amplifier IC capable of delivering 3Watts of out put to 4 Ohm loads. MAX9710 can be operated from a single 4.5V to 5.5V power supply , makes it ideal for hand held applications.The IC for 3 Watt stereo amplifier circuit also features thermal overload protection.

Circuit Schematics 3 Watt  Stereo Amplifier MAX 7910 

3 Watt stereo amplifier circuit 

This  3 Watt stereo amplifier circuit  is suitable for small power audio devices such as radio sets and portable CD players. 5 V DC power supply is used for powering the  3 Watt stereo amplifier circuit. 6V battery with an IN 4007 diode series to the positive terminal of it can also be used instead of 5 V DC supply. The  3 Watt stereo amplifier circuit will get a supply voltage approximately 5 V after 0.7 V voltage drop across diode.

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Output Relay Delay Audio Amplifier Diagram Circuit

This is a simple circuit which I built to one of my audio amplifier projects to control the speaker output relay. The purpose of this circuit is to control the relay which turns on the speaker output relay in the audio amplifier. The idea of the circuit is wait around 5 seconds ofter the power up until the speakers are switched to the amplifier output to avoid annoying "thump" sound from the speakers. Another feature of this circuit is that is disconnects the speaker immediately when the power in the amplifier is cut off, so avoiding sometimes nasty sounds when you turn the equipments off.

Circuit diagram:

Audio Amplifier Output Relay Delay Circuit Diagram

Component list
C1 = 100 uF 40V electrolytic
C2 = 100 uF 40V electrolytic
D1 = 1N4007
D2 = 1N4148
Q1 = BC547
R1 = 33 kohm 0.25W
R2 = 2.2 kohm 0.25W
RELAY 24V DC relay, coil resistance >300 ohm

Circuit operation:

Then power is applied to the power input of the circuit, the positive phase of AC voltage charges C1. Then C2 starts to charge slowly through R1. When the voltage in C2 rises, the emitter output voltage of Q1 rises together with voltage on C2. When the output voltage of Q2 is high enough (typically around 16..20V) the relay goes to on state and the relay witches connect the speakers to the amplifier output. It takes typically around 5 seconds after power up until the relay starts to conduct (at absolute time depends on the size of C2, relay voltage and circuit input voltage). When the power is switched off, C1 will loose its energy quite quickly. Also C2 will be charged quite quickly through R2. In less than 0.5 seconds the speakers are disconnected from the amplifier output.

Notes on the circuit:
This circuit is not the most accurate and elegant design, but it has worked nicely in my small home-built PA amplifier. This circuit can be also used in many other applications where a turn on delay of few seconds is needed. The delay time can be increased by using bigger C2 and decreased by using a smaller C2 value. Note that the delay is not very accurate because of simplicity of this circuit and large tolerance of typical electrolytic capacitors (can be -20%..+50% in some capacitors).

Author: Tomi Engdahl

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10 2 Surround Sound Systems

10.2 channel surround is the yet to come surround sound machinery so as to residential by THX corporation, the pet name itself, 10.2 is an cutting edge version of 5.1 tools but 10.2 is twice like mild as 5.1. concerning a 10.2 surround sound 14 channels are used. This includes five front speakers, five surround channels, two LFE and two heights, plus the addition of a instant associate-woofer. This equipment is considered as impending TRUEHD.The Diagram of a 10.2 TrueHD setup is publicized less than.

10.2 Surround Sound Systems

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50W Circuits Car Subwoofer Amplifier

The Car Subwoofer Amplifier 50W Circuit was posted by the side of trendy kind Amplifier. Please examine carefully and look on circuit design pictures of Car Subwoofer Amplifier 50W Circuit to catch aspect in sequence.

50W Circuits Car Subwoofer Amplifier 

This car stereo amplifier with TDA1562Q so as to can output 50W of audio power. at this time’s the complete incline :

2 resistors 1 KOhms

2 resistors 4,7 KOhms

2 resistors 100 KOhms

2 resistors 1 MOhms

4 capacitors 470 nF LCC 63V

4 capacitors 10 µF 63V radiaux

6 capacitors 4 700 µF 25V radiaux

2 capacitors 100 nF LCC

1 capacitor 10.000µF 25V radial

2 x LED

2 x TDA1562Q

2 switches unipolaires

2 heatsink (Rth <2.5°c/w) (+ pasta termica)

TDA7000 Single Chip FM Radio

This fm radio series fm radio receiver circuit that uses a single ic TDA.

Quite easy to make this fm radio circuit, where all functions can be done by IC TDA, so we only add to the technical components only. External components are intended to support so you can determine its own range of frequencies to be used. Actually if you want to have the radio equipment are satisfactory you can buy a radio market. Now this type of radio is very varied and the prices varying as well. To be sure with the money of 30 thousand you can get the fm radio with satisfactory quality. Because now the most sold radio is using digital functions, unlike the more dominant is the first transistor radio. But if you are a hobby with experimental electronics, not the rupiah value but which you consider the value of their knowledge.

For the working principle of this circuit does not really exist that must be addressed because all the functions already performed by the internal circuit is ic TDA. That if we do a surgical series is in the ic, the result will not be much different circuits fm radio receiver in general.

Component List:

1. IC TDA 7000

2. Resistor: 100 Kohm, 22 Kohm 100 Kohm and potensio

3. Capacitors: 39 pF, 37 pF, 220 nF, 22 nF, 10 nF, 180 pF, 150 pF, 100 nF, 330 pF, 220 pF, 3.3 nF, 330 pF, 3.3 pF, 220 nF, 1.8 nF, 1.8 nF, 25-50 pF

4. Inductors: 56 NH (2 pieces)

5. Loudspeaker

6. Antenna

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1 25V to 12Vdc Variable Output Low Noise

This circuit is DC converter low voltage , 12V from be 1.25V to 10Vdc by can give current topmost get about 1.5A. You should use IC number LM317K because have electric many power more the number LM317T. By should hold heat sink. That have large-sized with. The R4 use for fine decorate voltage output. The C1,C3 , and , C2 , for decrease all noise well. The detail is other , see in the circuit.
circuit source by joe (aircraftdesigner)

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PIC18F2620 Etching pan rocker

Some people consider PCB etching as a tedious task. One has to have extra care in handling the etchant – which stains, one needs to keep an eye on it to avoid over etching and one needs to rock the etching pan to speed up the etching process.

To make life a lot easier for hobbyists Graham came up with an ingeniously simple way of automating the rocking motion for the etching pan. He attached a servo motor on a pivot where the etching pan can tilt on both directions. Using a PIC18F2620 to send digital pulses he controls the back and forth motion of the servo which in turn gives the etching pan a rocking motion. Rock A By etching pan.

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Petrol Gas Switch For A Pajero circuit and explanation

My current vehicle, a Pajero, was modified for dual fuel - ie, petrol and gas. However, its necessary to run the vehicle on petrol at regular intervals to stop the injectors from clogging up. This simple circuit allows the vehicle to be started using petrol and then automatically switches it to gas when the speed exceeds 45km/h and the brake pedal is pressed. Alternatively, the vehicle may be run on petrol simply by switching the existing petrol/gas switch to petrol. You can also start the vehicle on gas by pressing the brake pedal while starting the vehicle. The circuit is based on an LM324 dual op amp, with both op amps wired as comparators. It works like this: IC1a buffers the signal from the vehicles speed sensor and drives an output filter network (D1, a 560kO resistor and a 10µF capacitor) to produce a DC voltage thats proportional to the vehicles speed.

Circuit diagram:

This voltage is then applied to pin 5 of IC1b and compared with the voltage set by trimpot VR1. When pin 7 of IC1b goes high, transistor Q1 turns on. This also turns on transistor Q2 when the brake pedal is pressed (pressing the brake pedal applies +12V from the brake light circuit to Q2s emitter). And when Q2 turns on, relay 1 turns on and its contacts switch to the gas position. Trimpot VR1 must be adjusted so that IC1bs pin 7 output switches high when the desired trigger speed is reached (ie, 45km/h). In effect, the speed signal is ANDed with the brake light signal to turn on the relay. The vehicle has been running this circuit for several years now and is still running well, with no further injector cleans required.

Author: J. Malnar - Copyright: Silicon Chip Electronics

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9v Portable Headphone Amplifier circuit and explanation

High Quality One-IC unit, Low current consumption-After several requests by correspondents, the decision of designing a 9V powered Headphone Amplifier was finally taken. The main requirement was to power the circuit by means of a common, PP3 (transistor radio) alkaline battery. So, implementing a low current drawing circuit was absolutely necessary, though preserving a High Quality performance.

Circuit Diagram:

Large View

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Parts:

P1 = 22K
R1 = 18K
R2 = 68K
R3 = 68K
R4 = 68K
R5 = 18K
R6 = 68K
C1 = 4.7uF-25v
C2 = 4.7uF-25v
C3 = 22pF
C4 = 220uF-25v
C5 = 220uF-25v
C6 = 4.7uF-25v
C7 = 22pF
C8 = 220uF-25v
J1 = 3.5mm Stereo Jack
B1 = 9V Alkaline Battery
IC1 = NE5532-34
SW1 = SPST Toggle Switch

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More:

• The appearance of the 5534 low-noise op-amp at a reasonable price was much appreciated by audio designers. It is now difficult or impossible to design a discrete stage that has the performance of the 5534 without quite unacceptable complexity.
• 5534 op-amps are now available from several sources, in a conventional 8-pin d.i.l. format. This version is internally compensated for gains of three or more, but requires a small external capacitor (5-15pF) for unity-gain stability. The 5532 is a very convenient package of two 5534s in one 8-pin devices with internal unity-gain compensation, as there are no spare pins.
• The 5534/2 is a low-distortion, low-noise device, having also the ability to drive low-impedance loads to a full voltage swing while maintaining low distortion. Furthermore, it is fully output short-circuit proof. Therefore, this circuit was implemented with a single 5532 chip forming a pair of stereo, inverting amplifiers, having an ac gain of about 3.5 and capable of delivering up to 3.6V peak-to-peak into a 32 Ohm load (corresponding to 50mW RMS) at less than 0.025% total harmonic distortion (1kHz & 10kHz).

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Source : www.redcircuits.com

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For Bicycles Rear Light After Glow circuit and explanation

This article is of interest only to readers whose bicycle lights are powered by a dynamo. The laws on bicycle lights in the United Kingdom are stricter than in other countries and a dynamo is, therefore, a rarity in this country. From the point of view of traffic safety it is advisable (in UK obligatory) for cyclists to have the rear lamp of their bicycle to light even when they are at standstill. In principle, it is not very difficult to modify the existing rear light with afterglow: all this needs is a large enough energy reservoir. Since the after-glow is required for short periods of time only, a battery is not required: a large value capacitor, say, 1 F, is quite sufficient.

As the diagram shows, in the present circuit, the normal rear light bulb is replaced by two series-connected bright LEDs, D2 and D3. These are clearly visible with a current of only 6 mA (compared with 50 mA of the bulb). The current is set with series resistor R1. The LEDs are shunted by the 1 F capacitor, C1. Since the working voltage of this component is only 5.5 V, it is, in spite of its high value, physically small. An effective regulator is needed to limit the dynamo voltage adequately. Normal regulators cannot be used here, since they do not work at low voltages. Moreover, such a device would discharge the capacitor when the cycle is at standstill.

Rear Light After Glow Circuit Diagram

Fortunately, there is a low-drop type that meets the present requirements nicely: the Type LP2950CZ5.0. Of course, the dynamo output voltage needs to be rectified before it can be applied to the regulator. In the present circuit, this is effected by half-wave rectifier D1 and buffer capacitor C2. Diode D1 is a Schottky type to keep any losses low – important for this application, because the ground connection via the bicycle frame usually causes some losses as well. The value of buffer capacitor has been chosen well above requirements to ensure that C1 is charged during the negative half cycles of the dynamo voltage.

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TL431 Regulator Adjustable Explanation and circuit

This be simple Adjustable voltage regulator power supply circuit, at use integrated number circuit TL431. By from the circuit can fine volt 3V – 30V, depend on feed volt supply input and change the value R2 , R1. It follow a formula calculates Vout = (1+R1/R2) , Vref = 3V-30V , but this circuit gives current get not tall 100mA only. It just if want to enhance current , must use the transistor helps to enlarge current, such as 2N3055, TIP41 numbers or the other.

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Breadboard module using A PIC16F628A

You don’t usually see microcontroller projects in a breadboard and I’ll give you one reason why – microcontrollers require some external components that eventually consumes the prototyping space in a breadboard. This is one of the reasons why hobbyists prefers to make/test projects in a custom PCB rather than the good old breadboard.

To remedy the dilemma of prototyping a PCB just to test a microcontroller circuit, R-B had this very fancy idea of making a breadboard module for a microcontroller. The module’s main part is a PIC16F628A, all the external components to make the microcontroller functional is also placed in the board – oscillator crystal, pull up resistor for the MCLR and even the reset button are already in the board. The only pins that sticks out of the module are the I/O pins and the power pins. Now people can verify microcontroller circuits without fabricating a specific board.

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IC 4047 2N3055 with PCB Inverter 100W

This circuit power Inverter 100W, so input voltage 12V (battery 12V)
to output volt 220V ac 50HZ, it is asy circuit because less component to use.
It use IC 4047 Squarewave Oscillator 50HZ and
Power Transistor 2N3055 x 2 For driver transformer 220V ac to OUTPUT Power 100W min.

Circuit Inverter 100W by IC 4047 + 2N3055

PCB Inverter 100W by IC 4047 + 2N3055
Source: 97 Electron Circuit

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12A, 100V, 0.300 Ohm, P-Channel Power MOSFETs

These are P-Channel enhancement mode silicon gate power
field effect transistors. They are advanced power MOSFETs
designed, tested, and guaranteed to withstand a specified
level of energy in the breakdown avalanche mode of
operation. All of these power MOSFETs are designed for
applications such as switching regulators, switching
convertors, motor drivers, relay drivers, and drivers for high
power bipolar switching transistors requiring high speed and
low gate drive power. The high input impedance allows these
types to be operated directly from integrated circuits.
Formerly developmental type TA17511.
 
 
Features

• 12A, 100V
• rDS(ON) = 0.300Ω
• Single Pulse Avalanche Energy Rated
• SOA is Power Dissipation Limited
• Nanosecond Switching Speeds
• Linear Transfer Characteristics
• High Input Impedance
• Related Literature
- TB334, “Guidelines for Soldering Surface Mount
Components to PC Boards”
 
download irf9530 datasheet

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IC 741 2N3055 Power Amp OCL 70w

Younger brothers and sisters a student takes an interest to build electronics project sends a teacher. I then choose this circuit , because build easy be valuable certainly. It is Main Power Amplifier Circuit 70Watt RMS sizes are model OCL Class AB. Use pillar equipment be IC 741 and Transistor 2N3055,MJ2955 a little this equipment circuit. If friends want get electric tall power about 70Watt should use Voltage Supply +38V , and -38V. The usability should fine VR1 be appropriate. Request a friend has fun to listen the music from Amp Circuit , please sir.

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Variable DC Power Supply Circuit Diagram

This project provides the schematic & the parts list needed to construct a simple DC Power Supply from an input power supply of 7-20 V AC or 7-30V DC. This project will come in handy in case you use plenty of batteries for your basic electronics project.

Two DC voltage outputs are available; is a fixed regulated 5V for TTL use. The other output is variable from 5V upwards. The maximum output voltage depends on the input voltage. The specified maximum input DC voltage to the regulator is 35V. The maximum input voltage must be two volts higher than the regulated output voltage.

Variable DC Power Supply Circuit Diagram

The DC Power Supply circuit is based around the 7805 voltage regulator. Its only three connections input, output & ground & it provides a fixed output. The last digits of the part number specify the output voltage, e g. 05, 06, 08, ten, 12,15, 18, or 24. The 7800 series provides up to one amp load current & has on-chip circuitry to close down the regulator if any attempt is made to operate it outside its safe operating area.It can be seen that theres in fact separate circuits in this power supply. 7805 is directly connected as a fixed 5V regulator. The second 7805 has a resistor divider network on the output. A variable 500 ohm potentiometer is used to vary the output voltage from a maximum of 5V up to the maximum DC voltage depending on the input voltage. It will be about 2V below the input DC voltage.

The capacitor across the output improves transient response. The giant capacitor across the input is a filter capacitor to help smooth out ripple in the rectified AC voltage. The larger the filter capacitor the lower the ripple.

For tiny applications the heat sinks wont be needed. The tab on the regulator will dissipate 2W at 25 o C in air. (This is equivalent, for example, to an input voltage of 9V, an output of 5V & drawing 500 m A.) However, as your projects get bigger they will draw more current from the power supply and the regulators will operate at a higher temperature and a heat sink will be needed. You can basically add voltage & current meters to it and put it in to an appropriate plastic case connected to a transformer.

Trouble Shooting Procedure

An LED has been put in to the output of the fixed 5V regulator to indicate that the circuit is working. Poor soldering is the most likely reason that the circuit does not work. Check that all the soldering is done properly. Check that all parts are in their correct position on the PCB. Other items to check are to make sure that the regulators, electrolytic capacitor & bridge rectifier are inserted in the correct orientation.

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Constructing your own Dual Power Supply Rise

Many times the hobbyist desires to have a simple, dual power supply for a project. Existing power supplies may be large either in power output or physical size. a simple Dual Power Supply is necessary.For most non-critical applications the best & simplest choice for a voltage regulator is the 3-terminal type.The three terminals are input, ground & output.

The 78xx & 79xx series can provide up to 1A load current & it have on chip circuitry to prevent damage in the event of over heating or excessive current. That is, the chip basically shuts down than blowing out. These regulators are cheap, simple to make use of, & they make it practical to design a method with plenty of P C Bs in which an unregulated supply is brought in & regulation is done locally on each circuit board.

This Dual Power Supply project provides a dual power supply. With the appropriate choice of transformer & 3-terminal voltage regulator pairs you can basically build a tiny power supply delivering up to amp at +/- 5V, +/- 9V, +/- 12V, +/-15V or +/-18V. You require to provide the middle tapped transformer and the 3-terminal pair of regulators you require:7805 & 7905, 7809 & 7909, 7812 & 7912, 7815 & 7915or 7818 & 7918.

The user must pick the pair they needs for his particular application.

Note that the + & - regulators do not must be matched: you can for example, use a +5v & -9V pair. However,the positive regulator must be a 78xx regulator, & the negative a 79xx. They have built in plenty of safety in to this project so it ought to give plenty of years of continuous service.

Transformer
This Dual Power Supply design makes use of a full wave bridge rectifier coupled with a centre-tapped transformer. A transformer with a power output rated at at least 7VA ought to be used. The 7VA rating means that the maximum current which can be delivered without overheating will be around 390mA for the 9V+9V tap; 290mA for the 12V+12V and 230mA for the 15V+15V. If the transformer is rated by output RMS-current then the worth ought to be divided by one.2 to get the current which can be supplied. For example, in this case a 1A RMS can deliver 1/(one.2) or 830mA.

Rectifier

They use an epoxy-packaged four amp bridge rectifier with at least a peak reverse voltage of 200V. (Note the part numbers of bridge rectifiers are not standardised so the number are different from different manufacturers.) For safety the diode voltage rating ought to be at least to times that of the transformers secondary voltage. The current rating of the diodes ought to be two times the maximum load current that will be drawn.

Filter Capacitor
The purpose of the filter capacitor is to smooth out the ripple in the rectified AC voltage. Theres dual amount of ripple is determined by the worth of the filer capacitor: the larger the worth the smaller the ripple.The two,200uF is an appropriate value for all the voltages generated using this project. The other consideration in choosing the correct capacitor is its voltage rating. The working voltage of the capacitor has to be greater than the peak output voltage of the rectifier. For an 18V supply the peak output voltage is one.4 x 18V, or 25V. So they have selected a 35V rated capacitor.

Regulators

The unregulated input voltage must always be higher than the regulators output voltage by at least 3V in order for it to work. If the input/output voltage difference is greater than 3V then the excess potential must be dissipated as heat. Without a heat sink three terminal regulators can dissipate about two watts. A simple calculation of the voltage differential times the current drawn will give the watts to be dissipated. Over two watts a heat sink must be provided. If not then the regulator will automatically turn off if the internal temperature reaches 150oC. For safety it is always best to make use of a small heat sink even in case you do not think you will need.

Stability

C4 & C5 improve the regulators ability to react to sudden changes in load current & to prevent uncontrolled oscillations.

Decoupling

The mono block capacitor C2 & C6 across the output provides high frequency decoupling which keep the impedance low at high frequencies.

LED

Two LEDs are provided to show when the output regulated power is online. You do not must make use of the LEDs in the event you do not require to. However, the LED on the negative side of the circuit does provide a maximum load to the 79xx regulator which they found necessary in the coursework of testing. The negative 3-pin regulators did not like a zero load situation. They have provided a 470R/0.5W resistors as the current limiting resistors for the LEDs.

Diode Protection

These protect chiefly against any back emf which may come back in to the power supply when it supplies power to inductive lots. They also provide additional short circuit protection in the case that the positive output is connected by accident to the negative output. If this happened the usual current limiting shutdown in each regulator may not work as intended. The diodes will short circuit in this case & protect the two regulators.

Dual Power Supply Schematic Diagram

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Build Motorcycle Alarm Circuit Diagram

This is a Motorcycle Alarm 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 center-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. 

 Motorcycle Alarm Circuit Diagram

About tw1o minutes after the switches have been opened again, the alarm will reset. How long it takes to switch off depends on the characteristics of the actual components used. But, up to a point, you can adjust the time to suit your requirements by changing the value of C1.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 close to the power source. 

This protects the wiring. 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 it is energized while the ignition is on. Then every time you turn the ignition off, the alarm will set itself.When it`s 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 any thing else that`s 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.

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Build a Simple Emergency Light and Alarm Circuit Diagram

This Simple Emergency Light and Alarm Circuit Diagram is permanently plugged into a mains socket andNI-CD batteries are trickle-charged. When a power outage occurs,the lamp automatically illuminates. Instead of illuminating alamp, an alarm sounder can be chosen.When power supply is restored, the lamp or the alarm isswitched-off. A switch provides a “latch-up” function, in orderto extend lamp or alarm operation even when power is restored.Circuit operation:Mains voltage is reduced to about 12V DC at C2`s terminals, bymeans of the reactance of C1 and the diode bridge (D1-D4). Thusavoids the use of a mains transformer.

 Simple Emergency Light and Alarm Circuit Diagram

Trickle-charging current for the battery B1 is provided by theseries resistor R3, D5 and the green LED D6 that also monitorsthe presence of mains supply and correct battery charging.Q2 & Q3 form a self-latching pair that start operatingwhen a power outage occurs. In this case, Q1 biasing becomespositive, so this transistor turns on the self latching pair.

If SW3 is set as shown in the circuit diagram, the lampilluminates via SW2, which is normally closed; if set the otherway, a square wave audio frequency generator formed by Q4, Q5 andrelated components is activated, driving the loudspeaker.If SW1 is left open, when mains supply is restored the lamp orthe alarm continue to operate. They can be disabled by openingthe main on-off switch SW2.If SW1 is closed, restoration of the mains supply terminateslamp or alarm operation, by applying a positive bias to the Baseof Q2.

Notes:

Close SW2 after the circuit is plugged.Warning! The circuit is connected to 220Vac mains, then some parts in the circuit board are subjected to lethal potential! avoid touching the circuit when plugged and enclose it in a plastic box. 

Parts List
R1____________220K 1/4W Resistor
R2____________470R 1/2W Resistor
R3____________390R 1/4W Resistor
R4______________1K5 1/4W Resistor
R5______________1R 1/4W Resistor
R6_____________10K 1/4W Resistor
R7____________330K 1/4W Resistor
R8____________470R 1/4W Resistor
R9____________100R 1/4W Resistor

C1____________330nF 400V Polyester Capacitor
C2_____________10΅F 63V Electrolytic Capacitor
C3____________100nF 63V Polyester Capacitor
C4_____________10nF 63V Polyester Capacitor

D1-D5________1N4007 1000V 1A Diodes
D6______________LED Green (any shape)
D7___________1N4148 75V 150mA Diode

Q1,Q3,Q4______BC547 45V 100mA NPN Transistors
Q2,Q5_________BC327 45V 800mA PNP Transistors

SW1,SW2________SPST Switches
SW3____________SPDT Switch

LP1____________2.2V or 2.5V 250-300mA Torch Lamp

SPKR___________8 Ohm Loudspeaker

B1_____________2.5V Battery (tw1o AA NI-CD rechargeable cells wired in series)

PL1____________Male Mains plug

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Diagram engine compartment of 1970 Plymouth Belvedere GTX

This is engine compartment of 1970 Plymouth Belvedere GTX, Road Runner, And Satellite wiring diagram. It shows the various electrical circuits, fuses, distributor, etc.

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Simple Phase Shift Meter for Audio Frequency Signal

Simple phase shift measurement can be done by squaring both the measured and the reference, then compute the difference of the two signals. The accuracy of the circuit shown in the schematic diagram  below is 1% UP to 2000 cps.

This circuit is used in computers and for high speed analog instrumentation. Negative value for zero phase shift is indicated by the zero center DC ammeter, zero for 90′ phase shift and some maximum value for 180′ phase shift.

 Phase-Shift Meter for Audio Frequency Signal Circuit Diagram

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Simple Active ir Motion Detector Circuit Diagram

To explore how different motion detectors operate.To successfully build and test an ambient-light-ignoring active IR motion detector.

Background

 There are a wide variety of motion detectors available currently. To allow a better understanding of motion detectors,the following section provides a detailed description of a few different types.

Ultrasonic Motion Detectors

Ultrasonic transducers can be used to detect motion in an area where there are not supposed to be any moving objects.This type of motion detector is most commonly used in burglar alarm systems since they are very effective in this application.

 Figure 1 shows the operation of an ultrasonic motiondetector. There are tw1o transducers: one emits an ultrasonicwave and the other picks up reflections from the differentobjects in the area. The reflected waves arrive at the receiverin constant phase if none of the objects in the area are moving.If something moves, the received signal is shifted in phase. 

A phase comparator detects the shifted phase and sends a triggering pulse to the alarm.Ultrasonic motion detectors have certain advantages and disadvantages when compared with other types of motion detectors. The main advantages is that they are very sensitive and extremely fast acting. However, the largest problem with this type of motion detector is that it sometimes responds to normal environmental vibration that can be caused by a passing car or a plane overhead. Some types of motion detectors use infrared sensors to avoid this problem, but even these detectors have some problems.

 Passive Infrared Motion DetectorIn passive infrared motion detectors, a sensorcontaining an infrared-sensitive phototransistor is placed in thearea to be protected. Circuitry within the sensor detects theinfrared radiation emitted by the intruder`s body and triggersthe alarm. 

The problem with using this type of detector is that it can be falsely triggered by warm air movement or other disturbances that can alter the infrared radiation levels in an area. In order to prevent this problem, newer systems use tw1oinfrared sensors which monitor different zones within a protected area. Logic within system triggers the alarm only when the tw1o zones are activated in sequence, as would occur if a person walked through the protected area.

Active Infrared Motion Detector

Figure 2 shows the operation of an active infrared motion detector. In the active system each sensor consists oftw1o housings. One housing contains an infrared-emitting diode and an infrared-sensitive photo transistor. The other housing contains an infrared reflector.When positioned in front of an entrance to a protected area, the tw1o housings establish an invisible beam. A person entering the area interrupts the beam causing an alarm to be triggered. An active motion detector is much more reliable than a passive one, but it requires careful alignment when it is installed. The detector can be falsely triggered if one of the housings moves slightly and causes a discontinuous beam.

Project

 For our project, we decided to construct an activeinfrared motion detector. Originally, we wanted to build both anIR and an ultrasonic detector, but we decided that an ultrasonicdetector would require too much time for a three week project.However, we also decided that just building an IR motiondetector would probably be a trivial exercise. 

So, we decided to expand on the concept by building an ambient light ignoring motion detector.This type of motion detector uses the same basic concept as the active infrared motion detector. An interruption in a 5kHz modulated pulsating beam that is transmitted by an infrared diode and received by an infrared transistor sets off the alarm. A schematic of this motion detector is given in Figure 3.

 Figure 3. Ambient-Light-Ignoring Active Motion Detector

The circuit on the left is the transmitter circuit that establishes a 5 kHz modulated infrared beam. As you can see from the schematic of the receiver circuit, a resonance-handbarrow amplifier reduces the detector`s sensitivity to stray light. C1 and L1 in IC2A`s feedback loop cause the op amp to pass only those frequencies at or near the LED`s 5 kHz modulation rate. IC2B`s output increases when the received signal is sufficient to drop the negative voltage across C2 below the reference set by R2. The output of this circuit is then attached to some load resistance, which can be an alarm or, for demonstration purposes, an LED.

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Switch Mode Pre Regulator circuit diagram

Switch Mode Pre-Regulator Circuit

The botheration was that a voltage regulator had to bead the 18 volt capital ability accumulation voltage to 8 volts at 500ma to ability the CD player, crumbling 5 watts of ability and causing a lot of calefaction central the bunched unit. This ambit acts as an interference-free pre-regulator to abundantly abate the ability loss..

The achievement voltage of this ambit is artless by ability band fluctuations. Amount voltage aberration is alone abased on the on-resistance of Q2 and the amount of C2 (re: ripple). The achievement voltage can be set so that the ripple lulls are aloof aloft the drop-out voltage of the beeline regulator at best amount for best activity conservation. The college amount you aces for C2, the added activity you can save and the added abiding the pre-regulator’s achievement voltage.

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DIY Data Glove Interface Known as HandUSB

Overview

The project can be considered as futuristic as a data glove which can be connected through USB instead of RS232 in order to become an alternative controller for the Pinch Glove fingertip contact glove.

Explanation

A very small SubD adapter housing is used to fit this device as it supports USB standby and consumes low power with 20mA maximum. The device is much faster in responsiveness than the GL-8001 and may later support a USB remote wakeup feature. The project is the reconstruction of a Fakespace GL-8001 device with fully compatible serial interface through USB. The crystal and capacitors can be omitted using the updated V-USB driver. In place of single resistors and multi-diodes, resistor arrays were employed so that it will be easier to populate in case.

V-USB is the basis of writing the firmware where a serial port occurs ready for communication fully compatible to the original GL-8001 box when plugging this device. The baud rate setting is not critical as for V-USB-CDC projects while Windows and Linux have built-in drivers.

A representation of hand interaction is possibly used by Pinch gloves in order to productively work within 3D computer simulation.

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UltraSonic Radar Ultrasonic Radar Circuit Board 2 This is a ultrasonic radar project with many practical applications in security and alarm systems

This is a ultrasonic radar project with many practical applications in security and alarm systems for homes, shops and cars. It consists of a set of ultrasonic receiver and transmitter which operate at the same frequency. When something moves in the area covered by the circuit the circuit’s fine balance is disturbed and the alarm is triggered. The circuit is very sensitive and can be adjusted to reset itself automatically or to stay triggered till it is reset manually after an alarm.

Adjustments
This kit does not need any adjustments, if you follow the building instructions.

Warning
If they are used as part of a larger assembly and any damage is caused, our company bears no responsibility.

While using electrical parts, handle power supply and equipment with great care, following safety standards as described by international specs and regulations.

If it does not work
Check your work for possible dry joints, bridges across adjacent tracks or soldering flux residues that usually cause problems. Check again all the external connections to and from the circuit to see if there is a mistake there.

See that there are no components missing or inserted in the wrong places.
Make sure that all the polarised components have been soldered the right way round. Make sure that the supply has the correct voltage and is connected the right way round to your circuit. Check your project for faulty or damaged components.

If everything checks and your project still fails to work, please contact your retailer and the Smart Kit Service will repair it for you.

Parts List
R1 = 180 KOhm C1, 6 = 10uF/16V TR1, 2, 3 = BC547 , BC548
R2 = 12 KOhm C2 = 47uF/16V P1 = 10 KOhm trimmer
R3, 8 = 47 KOhm C3 = 4,7 pF P2 = 47 KOhm trimmer
R4 = 3,9 KOhm C4, 7 = 1 nF IC1, 2 = 741 OP-AMP
R5, 6, 16 = 10 KOhm C5 = 10nF IC3 = 4093 C-MOS
R7, 10, 12, 14, 17 = 100 KΩ C8, 11 = 4,7 uF/16V R = TRANSDUCER 40KHz
R9, 11 = 1 MOhm C9 = 22uF/16V T = TRANSDUCER 40KHz
R13, 15 = 3,3 KOhm C10 = 100 nF D1, 2, 3, 4 = 1N4148
C12 = 2,2 uF/16V
C13 = 3,3nF
C14 = 47nF


Source: UltraSonic Radar 

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