Showing posts with label using. Show all posts
Showing posts with label using. Show all posts

Friday, October 24, 2014

Adjustable Symmetrical Power Supply Using LM317 and LM337

The circuit was designed to provide an adjustment with a power supply that is symmetrically designed while providing a voltage range of 1.25V to 30V at 1A current. LM317 – an adjustable 3-terminal positive voltage regulator capable of supplying in excess of 1.5A over an output voltage range of 1.2V to 37V and requires only two external resistors to set the output voltage due to its internal current limiting, thermal shutdown and safe area compensation, making it essentially blow-out proof LM337 – an adjustable 3-terminal positive voltage regulator capable of supplying in excess of 5A used as battery chargers, constant current regulators, and adjustable power supplies due to its features such as protected output from short circuit, product enhancement tested, current limit constant with temperature, guaranteed thermal regulation, adjustable output down to 1.2V, guaranteed 5A, and guaranteed 7A peak output current.

Adjustable Symmetrical Power Supply Using LM317 and LM337

The circuit will serve as a voltage converter with an input voltage of 35 V to produce an output voltage of 1.25 V to 30 V. The positive voltage is being handled by LM317 IC while the negative voltage is handled by LM337. The circuit can provide an output current of 1 A. During the production of 1 A current, the regulator is dissipating too much heat and without the presence of a heatsink, the regulator may get damaged.

Using these types of regulators provide features such as low noise and low price in the market. It can be made operational even with few components used. The only disadvantage that it will impose is the poor conversion efficiency. With the output of 35 V to 5 V, the efficient ratio of the output power with the input power is less than 42%. This is the reason why the switching regulator became cheap recently although the number of external components to be connected is minimally increased. These regulators will work with better efficiency when used in case where current is more than 1A for more than 15 V and 0.4 A for less than 15 V from the power supply. Each regulator is adjusted for single positive and negative voltage output using the 10K ohms potentiometers RV1 & RV2. For dual outputs, a dual connected potentiometer RV3 is made to operate by switch S1. The visual indication on the voltmeter V1 is shown using the switch S2.
  • R1-2=270ohms
  • R3-4=2.2Kohms
  • R5-6=10Kohms
  • C1-5=100uF/63V
  • C2-4=100nF/100V
  • C3-8=10uF/25V
  • C6-10=100uF/63V
  • C7-9=100nF/100V
  • RV1-2=10Kohms Lin.
  • RV3=2X10Kohms Lin.
  • IC 1=LM 317T
  • IC 2=LM 337T
  • D1-2=1N4001
  • D3-4=1N4001
  • L1-2=LED 3mm
  • F1-2=1A slow Blow Fuse
  • S1-2=2X ON-ON SW
  • V1=0-30V DC Voltmeter
The adjustable symmetrical power supply is suitable to be used in audio amplifiers, microphone amplifiers, op-amp applications, impedance converters and other devices that require regulated positive and negative DC supply, since the output current is 1 A.
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Thursday, October 23, 2014

Simple and hold circuit using op amp Circuits Diagram

As the name indicates , a sample and hold circuit is a circuit which samples an input signal and holds onto its last sampled value until the input is sampled again. Sample and hold circuits are commonly used in analogue to digital converts, communication circuits, PWM circuits etc. The circuit shown below is of a sample and hold circuit based on uA 741 opamp , n-channel E MOSFET BS170 and few passive components.

Description

As the name indicates , a sample and hold circuit is a circuit which samples an input signal and holds onto its last sampled value until the input is sampled again. Sample and hold circuits are commonly used in analogue to digital converts, communication circuits, PWM circuits etc. The circuit shown below is of a sample and hold circuit based on uA 741 opamp , n-channel E MOSFET BS170 and few passive components.

In the circuit MOSFET BS170 (Q1) works as a switch while opamp uA741 is wired as a voltage follower. The signal to be sampled (Vin) is applied to the drain of MOSFET while the sample and hold control voltage (Vs) is applied to the source of the MOSFET. The source pin of the MOSFET is connected to the non inverting input of the opamp through the resistor R3. C1 which is a polyester capacitor serves as the charge storing device. Resistor R2 serves as the load resistor while preset R1 is used for adjusting the offset voltage.
During the positive half cycle of the Vs, the MOSFET is ON which acts like a closed switch and the capacitor C1 is charged by the Vin and the same voltage (Vin) appears at the output of the opamp. When Vs is zero MOSFET is switched off and the only discharge path for C1 is through the inverting input of the opamp. Since the input impedance of the opamp is too high the voltage Vin is retained and it appears at the output of the opamp.

The time periods of the Vs during which the voltage across the capacitor (Vc) is equal to Vin are called sample periods (Ts) and the time periods of Vs during which the voltage across the capacitor C1 (Vc) is held constant are called hold periods (Th). Taking a close look at the input and output wave forms of the circuit will make it easier to understand the working of the circuit.

Circuit diagram

 Sample and Hold circuit using uA741 opamp

Input and output waveforms.

sample and hold waveforms
Input and output waveforms - Sample and hold circuit

Notes

  • The circuit can be assembled on a vero board.
  • Use +15V/-15V DC dual supply for powering the opamp.
  • Capacitor C1 must have minimum leakage current possible and thats why a polyester capacitor is used here.
  • Mount the IC uA741 on a holder.
  • The type number of the MOSFET Q1 is not very significant here and so substitution is possible if BS170 is not available.
  • BS170 is a 60V, 500mA n-channel enhancement mode MOSFET available in TO-92 package.
  • Preset resistor R1 can be used for offset adjustments.
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200 Watt Amplifier Circuit Diagram using TDA2030

This is a 200 Watt Amplifier Circuit Diagram that uses a TDA2030 IC which is an audio power amplifier 200 watt low cost. The 200 watts can be achieved with a load impedance of 4 ohms. The TDA2030 can typically provide up to 14 watts into a 4 ohm load, but if used in bridge mode and we use some cheap power transistors we can get to 200 watt. The design of this amplifier circuit 200 watt audio is very simple and requires few external components. For best performance, you can use a source of 28 volts (+ / - 14 volts), not more than 44 volts (+ / - 20 volts).

 As you can see in the diagram, for this power amplifier circuit you need high capacity capacitors and a power supply high current. All transistors and ICS should be mounted on a heat sink to prevent damage by temperature. For small value resistors (1 ohm, 2.2 ohm) resistors use 2-5 watts.

 200 Watt Amplifier Circuit Diagram using TDA2030

200 Watt Amplifier Circuit Diagram

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LED Flasher Circuit Using 555 Timer IC

This is a simple LED flasher project that uses a common 555 timer IC for its operation. It is configured as an astable mode which means that its output is a square wave oscillator. Two LEDs are connected to its output in such a way that when one LED is ON, the other LED will turn OFF. 

It uses only 10 simple parts that are easily available at any electronic shops. Capacitor C2 charges exponentially through resistors R1, R2 and the resistance of the trimpot. When C2 has charged to about 2/3 VCC it stops charging and it discharges to about 1/3 VCC through R2 and the trimpot resistance via pin 7. This is the standard operation of a 555 timer. When a Vcc of 5 V to 15 V DC is applied to the circuit, the LED will start to flash.
The frequency of the flashing can be changed by varying the resistance of the potentiometer or trimpot. Parts List The parts list of the simple LED project is as shown below.
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ic HT82231 Animal sound generator using


This is an animal origin, a simple circuit. Interesting, because an IC package and a simple good
Operation of the circuit. This circuit, an IC, a number HT82231 IC package that has other audio source animals. The origin of the sound depends on the switch S1-S8 of switch.

Each is a different animal sounds and choose to press each LED1, LED2 lights alternately as it sounds they hear. The R1, R2 LED forward current limiting for each signal will come out on pin 19, to expand the force with Q1. There is also a sound that VR1 can be adjusted as soon as we hear. Or slow as you like C1, C2 prevents low-frequency noise. And high frequencies.
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Monday, October 20, 2014

On Demand WC Fan Using 555

In most WCs with an extractor the fan is connected to the lighting circuit and is switched on and off either in sympathy with the light or with a short delay. Since toilets are sometimes used for washing the hands or just for a quick look in the mirror, it is not always necessary to change the air in the smallest room in the house. The following circuit automatically determines whether there really is any need to run the fan and reacts appropriately. No odour sensor is needed: we just employ a small contact that detects when and for how long the toilet seat lid is lifted.

 On-Demand WC Fan Using 555 circuit diagram



If the seat lid is left up for at least some presettable minimum time t1, the fan is set running for another presettable time t2. In the example shown the contact is made using a small magnet on the lid and a reed switch mounted on the cistern. The rest is straightforward: IC2, the familiar 555, forms a timer whose period can be adjusted up to approximately 10 to 12 minutes using P2. This determines the fan running time. There are three CMOS NAND gates (type 4093) between the reed switch and the timer input which generate the required trigger signal. When the lid is in the ‘up’ position the reed switch is closed.

Capacitor C1 charges through P1 until it reaches the point where the output of IC1a switches from logic 1 to logic 0. The output of IC1b then goes to logic 1. The edge of the 0-1 transition, passed through the RC network formed by C2 and R2, results in the output of IC1c going to logic 0 for a second. This is taken to the trigger input on pin 2 of timer IC2, which in turn switches on the relay which causes the fan to run for the period of time determined by P2. The circuit is powered from a small transformer with a secondary winding delivering between approximately 8 V and 10 V. Do not forget to include a suitable fuse on the primary side.

The circuit around IC1b and IC1c ensures that the fan does not run continuously if the toilet seat lid is left up for an extended period. The time constant of P1 and C1 is set so that the fan does not run as a result of lavatorial transactions of a more minor nature, where the lid is opened and then closed shortly afterwards, before C1 has a chance to charge sufficiently to trigger the circuit.


Circuit Source: DIY Electronics Projects
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Battery Charger Circuit using Solar Cell Circuit Diagram

This is a circuit solar charger via USB cable emergency, it is an alternative circuit that uses solar cell and LM317 to regulate and make a recharge via USB for electronic equipment that can be IPODs, cell phones, MP3, tablets, etc..  

The simplicity of the circuit can be noted that he does not have much appeal, but its enough to make a simple battery charge. The Solar Cell should be 12v current should be enough for loading, 10% of the batteries.


 Battery Charger Circuit using Solar Cell Circuit Diagram


Battery Charger Circuit using Solar Cell Circuit Diagram

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Saturday, October 18, 2014

Indicator light using Windows Comparison Circuit Diagram

This circuit indicator light level using operational amplifier, LDR and indiction is by LEDs. There are a variety of LDR, its resistance varies from less than 100 ohms on a cloudy day in more than one megohm in complete darkness. A trimmer 2K was used to adjust the range of comparison. This configuration can also be used to indicate  the reconnoiter.
 
 Indicator light using Windows Comparison Circuit Diagram
 
Indicator light using Windows Comparison Circuit Diagram
 
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Friday, October 17, 2014

Using IC LA 4440 Laptop Audio Amplifier Circuit Diagram

This is the best IC LA 4440 Laptop Audio Amplifier circuit diagram, the audio output from the laptop’s built-in loudspeakers is low. A energy amplifier is needed to obtain a high volume. This is a simple circuit to amplify the laptop’s audio output. The circuit is made around energy amplifier IC LA 4440 (IC1) along with a couple of other components. LA4440 is really a dual funnel audio energy amplifier.

Using IC LA 4440- Laptop Audio Amplifier Circuit Diagram

Laptop-Audio-Amplifier-IC-LA-4440
Laptop Audio Amplifier Circuit Diagram

It’s low distortion over an array of low to high wavelengths with good funnel separation. Built-in dual channels enable it for stereo system and bridge amplifier programs. In dual mode LA4440 gives 6 w per funnel as well as in bridge mode 19- watt output. It’s ripple rejection of 46 dB. The audio result can be recognized by utilizing two 6-watt loudspeakers.

Connect hooks 2, 6 and ground of IC1 towards the stereo system jack which is combined with laptops. Assemble the circuit on the general-purpose PCB and enclose inside a appropriate cabinet. The circuit works off controlled 12V power supply. It’s suggested to make use of audio input socket within the circuit board. Make use of a proper warmth-sink for LA4440.
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Tuesday, October 14, 2014

LM4765 create 2 x 30 watt amplifier

A very simple 2 x 30 watt amplifier electronic circuit project can be designed using the LM4765 stereo audio amplifier IC capable of delivering typically 30W per channel of continuous average output power into an 8Ω load with less than 0.1% THD+N.
This 2 x 30 watt amplifier electronic circuit is very simple and require few external electronic parts and can be used in high end stereo TVs or some other audio applications .
Each amplifier has an independent smooth transition fadein/out mute and a power conserving standby mode which can be controlled by external logic.
Like many other audio amplifier ICs the LM4765 has many features like Temperature protection circuitry, SPiKe protection ( means that these parts are safeguarded at the output against overvoltage, undervoltage, overloads, including thermal runaway and instantaneous temperature peaks).
This audio amplifier electronic circuit project can be powered from a wide input voltage range from 20 volt up to 66 volts , but typically is required a dual 28 volts input ( take care because |Vcc|+|Vee|<60 volts .
The LM4765 has a sophisticated thermal protection scheme to prevent long-term thermal stress of the device. When the temperature on the die reaches 165°C, the LM4765 shuts down. It starts operating again when the die temperature drops to about 155°C, but if the temperature again begins to rise, shutdown will occur again at 165°C.
The audio IC must be mounted on a heat sink to keep the die temperature at a level such that the thermal protection circuitry does not operate under normal circumstances.
In this circuit diagram is represented just a part of the IC (one channel ) and numbers in parentheses represent pinout for amplifier B.2
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Saturday, October 4, 2014

Digital combination Lock using CD4013

This is a circuit Digital combination Lock is simple but effective ease of automatic reset. The circuit is about double flip-flop IC 4013. Two CD ICs are used here. Push button switches are used to enter the code number. One side of all push-button switches connected to +12 V DC. The other end of 2,3,6,8 buttons are connected to the clock input pins of filp-flops. The other end of other buttons switches are shorted and connected to the pin assembly filp-flops.

The relay coil is activated only if the code is entered in the correct order and if there is some variation, the lock is reset. Here is the correct code is 2368.When press 2 on the flop first round (IC1A) will be activated and the value of the data (pin9) is transferred to the Q output (pin13). Since the pin 9 is based the value is "0" and therefore the pin 13 is low. For further press the digits of the code in the correct sequence is "0" leads to the Q output (pin 1) of the last flip flop (IC2b). This makes the transistor and relay energised.The automatic restoration facilities managed by the resistance R11 and capacitor positive C2.The final capacitor C2 is connected to the pin assembly flops.When filp-transistor is turned on , the capacitor C2 begins to charge as the voltage across it becomes enough top-flops are reset. This makes the lock of a fixed amount of time and then automatically locks. The delay time can be adjusted by varying the values ​​of R11 and C2.
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Thursday, October 2, 2014

Simple Transistor Hfe Tester Circuit Diagram Using IC 741

  1. P1 is used to set a reference voltage derived from voltage UXY UD1 (or D2 for a PNP transistor). This means that l the setting of the potentiometer is directly proportional to the hpp; of the transistor under test and is independent of supply voltage.
  2. The voltage across R2 and the voltage set with P1 are compared by lC1 which is connected as a comparator. Potentiometer P1 is now set so that the LED at the output of the op-amp just lights or is just dimmed.
  3. This hfe tester is interesting because of its simplicity and because it enables the B of both PNP and NPN transistors to be measured.
  4. At this setting the voltage across the potentiometer is equal to the voltage across R2. Switch S1 is used to switch from NPN to PNP (or vice versa) by reversing the polarity of voltage UXY.
  5. LEDs D3 and D4 in the supply lines ensure that the input voltages to be measured are within the common mode range of the opamp used.
  6. Furthermore the measurement is independent of the supply voltage of the tester. As the diagram shows, the base current of the transistor under test travels via R1. Its base current IB is thus equal to The voltage drop across the collector resistor is hfe x IB x R2.
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Wednesday, October 1, 2014

Light Activated Switch Circuit Using IC 555

 A very useful light activated switch circuit can be made by utilising a single 555 timer with its trigger and threshold inputs connected together.
The schmitt has a very low input current (1.5uA) and can directly drive a relay taking up to 200mA of current. The circuit shows a 555 schmitt being used to energise a relay when the light level on a photoconductive cell falls below a preset value; the relay energises when the voltage on pins 2 and 5 is greater than 2/3Vcc and de-energises when the voltage falls  below I/3Vcc. This gives a hysteresis of 1/3Vcc, The circuit can be used in many other similar applications where  a high input impedance and low out- put impedance are required with the minimum component count.

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Monday, September 22, 2014

Create natural sound using ic MM5837

Normal voice we hear is from frequencies that are a combination of both high frequency and low frequency. Signal strength is not equal, will result in a different voice.

Operation of the circuit. When the power supply to IC1 by IC1 will work out the frequency produced by the pin 13 pin 3 is press the switch on left off. C to a value that will be connected to each circuit by the C makes the sound different.

Of the signal from pin 3 of IC1 is through R1 and VR1 is responsible for adjusting the strength of the signal will be expanded to IC2, which IC2 is IC amplifier with growing 1W signal that originates in the leg 5. The high frequency. And noise will be R3, C8 filter to ground the remaining signal is Retail Oil Link to C9 on the speakers.

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Sunday, September 21, 2014

30V Variable Power Supply Using LM317

This 30v variable power supply circuit is based on LM317  voltage regulator circuit . This LM317 30v variable power supply circuit can deliver high current (around 5 amps) and variable output voltage between 1.2 volts, up to 30 volts. The led D3 mounted on pin 6 at lm301 lights in constant current mode .

Circuit diagram 

Current limit can be adjusted using R2 potentiometer and the output voltage can be adjusted from 1.2 volts to 30 volts using R8 potentiometer . Input voltage for this variable power supply must be around 35 volts .For this power supply circuit you need to use LM317K circuit (in to3 package ) which must be mounted on a heatsink .
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Thursday, September 18, 2014

12Volt from USB port Using LT1618

Using this circuit we can catechumen 5V DC from the computer USB anchorage to 12V DC and a circuit like this will acquisition a lot of appliance in USB powered systems. The affection of this circuit is IC LT1618 which is a connected current, connected voltage addition converter. The IC has a advanced ascribe voltage ambit of 1.8 to 18V DC and achievement voltage can be up to 35V DC. 

In the circuit resistors R1, R2 sets the achievement voltage. Pin amount 9 is the abeyance pin, beneath than 0.3V to this pin will shut down the IC. Pin amount four is the accepted faculty acclimatize pin. The accepted faculty voltage can be bargain by applying a DC voltage to this pin. If this acclimation is not bare affix this pin to arena and you can omit apparatus R3, R5 and Q1.
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Saturday, September 13, 2014

Simple 4 Channel Video Amplifier using NJM2582

A very simple 4 channel video amplifier electronic schema project can be designed using NJM2582 ic suitable for video applications with SCART connector . Design of the schema is very simple and require few external electronic parts .

Circuit diagram :

Simple 4 Channel Video Amplifier Circuit Diagram

Some features of the NJM2582 are : Operating Voltage ±5V, +5V, +11V ; 6input 4output , 2input 1output Video SW , Internal LPF , 6dB Amplifier , Internal 75Ω Driver Circuit , DC output for SCART (FUNCTION SW, BLANKING) .

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Friday, September 12, 2014

60W Inverter using transistors

Here is the schema diagram of a fully transistorized inverter that can drive up to 60W loads. Transistors Q1 and Q2 forms a 50Hz astable multivibrator. The output from the collector of Q2 is connected to the input of the Darlington pair formed by Q3 and Q4.Similarly the output of Q1 is coupled to the input of the pair Q5 and Q6. The output from the Darlington pairs drive the final output transistors Q7 and Q8 which are wired in the push pull configuration to drive the output transformer.

Circuit diagram :

60W inverter using transistors Circuit Diagram

Notes.

  • The schema can be assembled on a vero board.
  • T1 can be a 230V primary to 9-0-9V, 6A secondary transformer.
  • Transistors Q4, Q6, Q7 and Q8 must be fitted with heat sinks.
  • Use a 12V, 7Ah battery for powering the inverter.
  • Slight adjustments can be made on the value of R3 and R4 to get exact 50Hz output.

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Tuesday, September 9, 2014

Emergency lighting using white LEDs Wiring diagram Schematic

This  Emergency lighting using white LEDs Circuit Diagram should be assembled only by experienced people and it is advisable to use a protection network, which can be a light bulb in series. For anyone who is thinking of making a system of emergency lighting and simple, this schema is a cheap and functional output. The schema is basically composed of a source AC / DC without a transformer, a charger, a system of automatic switching using a diode and a diode switch to change the brightness.

 Emergency lighting using white LEDs Circuit Diagram

emergency lighting using white leds circuit diagram




List of Components

R1 = 1M, ¼ Watt, 5%
R2 = 10K, ¼ Watt, 5%
R3 = 10 Ohms 1Watt
All resistors are LED = 22 Ohms, ¼ Watt
C1 = 205/400V, PPC
C2 = 100uF, 25V
Z1 = 9 V, 1 WATT
T1 = BD 140
All diodes = 1N4007
BATTERY = 6 volts 4 AH
LEDS = WHITE, HIGH EFFICIENCY, 5mm
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Friday, September 5, 2014

Radio Remote Control using DTMF

Here is a schema of a remote control unit which makes use of the radio frequency signals to control various electrical appliances. This remote control unit has 4 channels which can be easily extended to 12.








This schema differs from similar diagram in view of its simplicity and a totally different concept of generating the control signals. Usually remote control diagram make use of infrared light to transmit control signals. Their use is thus limited to a very confined area and line-of-sight. However, this schema makes use of radio frequency to transmit the control signals and hence it can be used for control from almost anywhere in the house. Here we make use of DTMF (dual-tone multi frequency) signals (used in telephones to dial the digits) as the control codes. The DTMF tones are used for frequency modulation of the carrier. At the receiver unit, these frequency modulated signals are intercepted to obtain DTMF tones at the speaker terminals. This DTMF signal is connected to a DTMF-to-BCD converter whose BCD output is used to switch-on and switch-off various electrical applicances (4 in this case). The remote control transmitter consists of DTMF generator and an FM transmitter schema. For generating the DTMF frequencies, a dedicated IC UM91214B (which is used as a dialler IC in telephone instruments) is used here. This IC requires 3 volts for its operation. This is provided by a simple zener diode voltage regulator which converts 9 volts into 3 volts for use by this IC. For its time base, it requires a quartz crystal of 3.58 MHz which is easily available from electronic component shops. Pins 1 and 2 are used as chip select and DTMF mode select pins respectively. When the row and column pins (12 and 15) are shorted to each other, DTMF tones corresponding to digit 1 are output from its pin 7. Similarly, pins 13, 16 and 17 are additionally required to dial digits 2, 4 and 8. Rest of the pins of this IC may be left as they are. The output of IC1 is given to the input of this transmitter schema which effectively frequency modulates the carrier and transmits it in the air. The carrier frequency is determined by coil L1 and trimmer capacitor VC1 (which may be adjusted for around 100MHz operation). An antenna of 10 to 15 cms (4 to 6 inches) length will be sufficient to provide adequate range. The antenna is also necessary because the transmitter unit has to be housed in a metallic cabinet to protect the frequency drift caused due to stray EM fields. Four key switches (DPST push-to-on spring loaded) are required to transmit the desired DTMF tones. The switches when pressed generate the specific tone pairs as well as provide power to the transmitter schema simultaneously. This way when the transmitter unit is not in use it consumes no power at all and the battery lasts much longer. The receiver unit consists of an FM receiver (these days simple and inexpensive FM kits are readily available in the market which work exceptionally well), a DTMF-to-BCD converter and a flip-flop toggling latch section. The frequency modulated DTMF signals are received by the FM receiver and the output (DTMF tones) are fed to the dedicated IC KT3170 which is a DTMF-to-BCD converter. This IC when fed with the DTMF tones gives corresponding BCD output; for example, when digit 1 is pressed, the output is 0001 and when digit 4 is pressed the output is 0100. This IC also requires a 3.58MHz crystal for its operation. The tone input is connected to its pin 2 and the BCD outputs are taken from pins 11 to 14 respectively. These outputs are fed to 4 individual ‘D’ flip-flop latches which have been converted into toggle flip-flops built around two CD4013B ICs. Whenever a digit is pressed, the receiver decodes it and gives a clock pulse which is used to toggle the corresponding flip-flop to the alternate state. The flip-flop output is used to drive a relay which in turn can latch or unlatch any electrical appliance. We can upgrade the schema to control as many as 12 channels since IC UM91214B can generates 12 DTMF tones. For this purpose some modification has to be done in receiver unit and also in between IC2 and toggle flip-flop section in the receiver. A 4-to-16 lines demultiplexer (IC 74154) has to be used and the number of toggle flip-flops have also to be increased to 12 from the existing 4
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