MATERIALS

Design & Construction of Intelligent security system for apartment

Design & Construction of Intelligent bank security system

Design & Construction of 2-way wired intercom

Design & Construction of Solar power auto street light

Design & Construction of Auto room light controller

Design & Construction of Numeric Controlled Door Locking System

Design & Construction of Automatic Bell Ringer

Design & Construction of Portable fm transmitter

Design & Construction of Remote control fan

Design & Construction of 500w audio amplifier

Design & Construction of Remote control ac lamp

Design & Construction of Intelligent emergency light

Design & Construction of Sensor operated automatic door open/close machine

Design & Construction of 3-input public addressing system

Design & Construction of Under and over voltage power protection system

Design & Construction of Remote control gate

Design & Construction of Generation of constant power supply using DC source

Design & Construction of 5KVA modified sine wave converter

Design & Construction of Sound activated device

Design & Construction of Automatic oven controller

Design & Construction of 200W Bass guitar power amplifier

Design & Construction of Temperature control incubator

Design & Construction ofAuto water level controller

Design & Construction of Power failure alarm with auto generator starting device

Design & Construction of UPS

Design & Construction of 60W power amplifier

Design & Construction of Audio isolation transformer

Design & Construction of FET amplifier

Design & Construction of Stereo power amplifier

Design & Construction of Home audio amplifier

Design & Construction of 100W audio amplifier

Design & Construction of Subwoofer audio amplifier

Design & Construction of Security beeper

Design & Construction of 180w amplifier

Design & Construction of 45W power amplifier

Design & Construction of Single chip 60W amplifier

Design & Construction of 600w amplifying circuit

Design & Construction of Home theatre audio amplifier

Design & Construction of High quality 150W power amplifier

Design & Construction of Mini microphone circuit

Design & Construction of 300w Hi-Fi amplifier

Design & Construction of Audio preamplifier with tone control

Design & Construction of 200W stereo amplifier

Design & Construction of Bass power amplifier

Design & Construction of Transistor power amplifier

Design & Construction of Headphone amplifier

Design & Construction of Sweeping tone alarm beeper

Design & Construction of 3-chanel microphone mixer

Design & Construction of Police siren

Design & Construction of 4-channel audio mixer

Design & Construction of Audio megaphone

Design & Construction of SCR tester

Design & Construction of Guitar headphone amplifier

Design & Construction of Guitar amp

Design & Construction of Op-amp booster design

Design & Construction of 5-channel equalizer

Design & Construction of 3-band dual graphic equalizer

Design & Construction of audio power amplifier

Design & Construction of 10-input Mixer amplifier

Design & Construction of Equalizer amplifier

Design & Construction of Tape-radio-mic audio input amplifier

Design & Construction of Tone control circuit

Effect of western TV program on Nigerian youths

effects of temperature on viscosity of water,milk and corn oil

Design and Construction of temperature control circuits

Design & Construction ofAlternating on-off switch

Design & Construction of Ac voltageregulator/stabilizer

Design & Construction of UPS power supply

Design & Construction of Variable power supply

Design & Construction of Dual power supply

Design & Construction of Audio power indicator

Design & Construction of Amplifier input module

Design & Construction of Transformer-less power supply

Design & Construction of Intruder alarm

Design & Construction of Power failure alarm

Design & Construction of Remote control ac lamp

Design & Construction of Car demobilizing system

Design & Construction of Car anti-theft device

Design & Construction of Miniature fm transmitter

Design & Construction of Auto intruder alarm

Design & Construction of Power supplies

Design & Construction of Automatic battery chargers

Design & Construction of Wailing alarm

Design & Construction of Rain activated alarm

Design & Construction of Beeper

Design & Construction of TV, AM, FM antenna booster 

Design & Construction of Water level controller

Design & Construction of Fuel/water level indicator

Design & Construction of Auto turn-off battery charger

Design & Construction of Dark/light activated alarm

Design & Construction of Power and audio amplifier

Design & Construction of 10-input microphone mixer

Design & Construction of Transistor organ

Design & Construction of 50/80w audio amplifier

Design & Construction of Headphone amplifier

Design & Construction of Solar panel

Design & Construction of solar water heater

Design & Construction of No pollution power generator

Design & Construction of Sound or Clap activated  alarm

water-dry indicator wind energy  generator

Design & Construction of power failure alarm

How to build a Radio

Power generation using wind turbines,

Resistance In Series & Parallel

Kirchhoff’s Law

Solar Photovoltaic Modules for Education

Home Wiring

Demonstration Type Transformer.

generation of wind energy

Generation of solar energy

Solar energy installation

water turbine power generation

solar power bicycle

solar Principle and design ofsolar panel

design and construction of astable  multivirator

solar water heater

No pollution power generator

Sound or Clap activated alarm

water-dry indicator

wind energy  generator

Alternating on-off switch

Ac voltageregulator/stabilizer

UPS power supply

Design & Construction ofVariable power supply

Design & Construction of Dual power supply

Design & Construction ofAudio power indicator

Design & Construction ofAmplifier input module

Design & Construction ofTransformer-less power supply

Design & Construction ofIntruder alarm

Design & Construction of Power failure alarm

Design & Construction of Remote control ac lamp

Design & Construction ofCar demobilizing system

Design & Construction of Car anti-theft device

Design & Construction of Miniature fm transmitter

Design & Construction of Auto intruder alarm

Design & Construction of Power supplies

Design & Construction ofAutomatic battery chargers

Design & Construction ofconstruction ofWailing alarm

Design & Construction ofRain activated alarm

Design & Construction of Beeper

Design & Construction of TV, AM, FM antenna booster 

Design & Construction of Water level controller

Design & Construction ofFuel/water level indicator

Design & Construction ofAuto turn-off battery charger

Design & Construction ofDark/light activated alarm

Design & Construction ofPower and audio amplifier

Design & Construction of10-input microphone mixer

Design & Construction ofTransistor organ

Design & Construction of50/80w audio amplifier

Design & Construction of Headphone amplifier

Design & Construction of Solar panel

Design & Construction of solar water heater

Design & Construction of No pollution power generator

Design & Construction of Sound or Clap activated  alarm

water-dry indicator
wind energy  generator

Design & Construction ofpower failure alarm

How to build a Radio

Power generation using wind turbines,

Resistance In Series & Parallel

Kirchhoff’s Law

Wheatstone Bridge

Solar Photovoltaic Modules for Education

Home Wiring

Demonstration Type Transformer.

generation of wind energy

Generation of solar energy

Solar energy installation

water turbine power generation

solar power bicycle

solar Principle and design of solar panel

design and construction of astable  multivirator

Design & Construction of solar water heater

design and construction of 2000w inverter system


design and construction of a d.c to a.c inveter system

the construction of a 3-phase motor operation indicator

construction of pvs conduit wiring system of two bedroom bungalow

construction of a 12 volt battery charger

construction of automatic change over with generator trip off

fm transmitter

the design and construction of mini radio broadcast transmitter and audio console using frequency modulation (fm) with power rating of 1 watt

contruction of an 500w transistor amplifier

the design and construction of a 40 watt hi-fi amplifier

design and construction of a 3 way inter-communication system

the design and construction of car controller using telemetry system

design and construction of a single phase automatic change over switch with phase selector

the design and construction of an inverter

the design and construction of a three phase automatic phase selector

design and construction of a two lane traffic light

the design and implementation of a four – way traffic light control circuit.

design and construction of a multiperpose security system with alarm and display

construction of 200w uninterruptible power supply

the design and construction of an uninterrupted power system (ups)
the design of a 500watts uninterruptible power supply with voltage leo indicator [inverter]

design and construction of an automatic phase selector

design and construction of power amplifier

the design and construction of electric arc welding machine

design and construction of uninterruptible power supply

design and construction of an audio amplifier

the design and construction of a dc to ac power inverter incorporated with an automatic switch over battery charger

design and construction of voltage inverter system with trickle charging system

design and construction of an automatic voltage stabilizer

construction of an automatic change over switch (3.7kva)

design and construction of sound detector with alarm system

design and construction of 25amps single phase automatic change over

design and construction of digital incubator

construction of an intruder alarm system

the design and implementation of electronics sequential sign patter display

the design and cosntruction of 1000kwa stabilizer

design and construction of 12volts car battery automatic charger with voltage level indicator and charging process display

design and construction of 45w audio power amplifier

design and construction of fire alarm system in a two storeyed building

design and construction of a 60 watts power amplifier

design and construction of a single phase auto-transformer of rating 1kva, 240v/110, 80 12v, 6v

design and construction of temperature control oven

Design & Construction of Police siren

ABSTRCT
A police siren is a loud noise making device used by police to get other drivers on the road out of their way.
Electronic sirens incorporate circuits such as oscillators, modulators, and amplifiers to synthesize a selected siren tone (wail, yelp, pierce/priority/phaser, hi-lo, scan, air horn, manual, and a few more) which is played through external speakers. It is not unusual, especially in the case of modern fire engines, to see an emergency vehicle equipped with both types of sirens. Often, police sirens also use the interval of a tri-tone to help draw attention.

This police siren simulated electronic project uses two 555 timers IC to generate a sound similar to the police siren. A single 556 timer IC which consists of two 555 timers can also be used. In this circuit, both of the timers are configured as astable circuit.

The first timer is configured as a square wave close to 1 Hz astable oscillator. The output of this timer is used to feed the control voltage of the second timer where it is subjected to frequency modulation. This frequency modulation will generate a tone similar to the siren used by the police.

The frequency of this tone generator can be varied by changing the value of potentiometer VR1. When set to its maximum value of 220k ohm, it will have a tone frequency of approximately 320 Hz.

When S1 is switched ON, the circuit will be powered ON and U1 will start to oscillate at a frequency given by the formula:

f = 1.44/[(R1 + 2R2)(E1)] 

= 1.44/[(10 + 2*82)(10)] Hz 

= 0.8 Hz 

This output frequency from pin 3 of U1 is fed into pin 5 of U2 where it is subjected to frequency modulation through resistor 10K. The tone generated can be varied by changing the values of potentiometer VR1.

Experiment with the sound and settle with the best sound of your choice. The output of U2 is used to drive a power transistor which in turn drives an 8 ohm speaker. Diode D2 is used to prevent the damage of transistor Q1 due to the back emf generated by the speaker during the ON/OFF driving of the speaker.

A good way to start is to assemble all the components on a breadboard and connecting all of them using jumper wires on the board. Power up the board using 9V DC power supply and test the functionality of the circuit before proceeding to solder them onto the PCB strip board.

HOW TO RECEIVE COMPLETE MATERIAL (I.E CHAPTER 1-5)
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ACCOMODATION: Free accommodation will also be given to any of our client who wishes to partner with us that love to know step by step and one-on-one on how to design and construction his or her project.

OUR TRAINING: we train individuals, students and IT students on how to repair, design and construct electronics gadgets

NOTE: we can also research any topic(s) that relate to topics or department on this site for you. And we also accept urgent work,that is, completing your project design and construction before a period of one week. And any of our clients who wish to know how to construct his or her project can also come to our office where he/she will learn step-by-step how to construct it so that at the end of the work he/she will be able to construct one for their own use. We also design tested OK project circuits for existence and non-existence project topics.

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