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Friday, December 27, 2013

Under voltage Indicator for Battery Equipment Circuit Diagram

This is the simple Under voltage Indicator for Battery Equipment Circuit Diagram. Due to the low duty cycle of flashing LED, the average current drain is 1 mA or less. The NE555 will trigger the LED on when the monitored voltage falls to 12 volts.The ratio of Rl to R2 only needs to he changed if it is desired to change the voltage point at which the LED is triggered.


Under voltage Indicator for Battery Equipment Circuit Diagram

Under voltage Indicator for Battery Equipment Circuit Diagram

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Thursday, December 26, 2013

Infrared IR Receiver Module Tester

Here is a tester for on-board testing of IR receiver modules used for remote control of TV sets and VCD players. The circuit is very simple and can also function as a remote tester. IR receiver modules are miniature IR receivers sensitive to pulsed infrared rays. These have a pin photo-diode and a preamplifier stage encased in an epoxy case that acts as the IR filter.

Infrared (IR) Receiver Module Tester
Infrared (IR) Receiver Module Tester Circuit Diagram
Internally, the module has an AGC, band-pass filter, demodulator and control circuit. Its output has a bipolar transistor with 80- to 100-kilo-ohm resistor in the collector. Normally, the collector output of the transistor is high and gives 5V at 5 mA. The output of the module is active-low and hence it sinks current when the pin photo-diode senses the presence of pulsed IR rays.

Infrared (IR) Receiver Module Tester

The IR receiver module is designed with high immunity against ambient light and is capable of continuous data transmission at up to 2400 bps or higher. The band-pass filter and AGC suppress unexpected noise to avoid false triggering. The module responds to the IR beam only if its carrier frequency is close to the centre frequency of the band pass.

Infrared (IR) Receiver Module Tester
IR Receiver Module Pinout
Working of the circuit is simple. Three mini crocodile clips are used to connect the circuit to the positive, negative and output of the module. If the module is properly working, its output remains 5 volts. This makes the cathode of LED1 high. So LED1 doesn’t glow and the buzzer remains silent. When you focus the remote handset onto the IR receiver and press any switch, the output of the IR receiver sinks current.

So LED1 starts flashing and the buzzer beeps in sync with the pulsations of the IR beam. On the other hand, if your IR receiver module is faulty, the output of the module does not sink current when you focus the remote handset towards the module and press any switch. So neither LED1 flashes, nor the buzzer beeps in sync with the pulsations of the IR beam.

Power to the circuit is obtained from a 9V PP3 battery and regulated to 5 volts by zener diode ZD1. Most of the IR receiver modules work only between 3 and 6 volts. Storage capacitor C1 releases current to make LED1 flash brightly. (EFY Note. We had used a TSOP1738 IR receiver module while testing. Fig. 2 shows the pin configuration of TSOP1738.)

Assemble the circuit on a small piece of matrix board and enclose in a small cabinet. Use a high-brightness red LED and a small buzzer for audio-visual indication. Connect points A, B and C to the crocodile clips using red, black and blue wires to connect to the pins of the module easily. For easy identification of pins, the pin assignment (front view) of some common IR receiver modules is shown in the table.
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Wednesday, December 25, 2013

It also has a special mode for pictures

 It also has a special mode for pictures of contacts and a World Card Mobile application

for capturing and reading business cards.
Videos can be captured in normal and MMS modes. Format options include MPEG4 and H.263. Highest resolution can be set at VGA (640x480 pixels). Recording limit has a number of options such as 10

seconds, 3 minutes, 2 MB, etc.This is a gadget which can add extra capability to your cellular phone. A cell phone booster with

a Bluetooth contrivance can set up a wireless connection with some other detailed devices with the same capability. Hence, it abolishes the requirement to use physical cables.This accessory help

you in providing the strong network along with the huge connectivity. Antenna Booster will help you in many ways. It provides the good connection so that you can easily talk to your relatives or

family members.Faceplates are generally used to give the trendy, classy, amazing, stylish, and the glossy look to your touchtone phones. They are available in the market in great abundance. You can

get them according to your need and make your cell also luxurious.
This is all about the accessories and its benefits, I hope after reading this article you will surely purchase the good and the stylish accessories for your handsets.
 Schools are looking to purchase mobile phone signal boosters. The misuse of cell phone boosters during class is causing the teachers to fight back. Not only is it a huge distraction during class

while teachers are trying to actually teach, but there is also concern that cheating is more prevalent with the ongoing texting.
In Des Moines, Iowa, one school board member was quoted by the Des Moines Record. "I dont think they have a place in the educational environment. The educational environment is supposed to be

about students learning and teachers teaching and teachers cant teach over a mobile phone. If a student is busy on the cell phone booster they arent learning. Its a distraction... and we need to

minimize the distraction."
What is the solution? With the FCC controlling signal boosters as well as signal boosters, and the law limiting signal boosters to use only by federal authorities, schools dont have much of a

chance to fight back that way.
One reader responded to the article in the Des Moines Register with an amusing suggestion to the problem. "Oh, For Crying-out-load. Just hang one of those shoe organizers next to the door and

require each student to check in their phones on entering the classroom, then they can retrieve them after class.
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9 line telephone sharer

     This circuit is able to handle nine independent telephones (using a single telephone line pair) located at nine different locations, say, up to a distance of 100m from each other, for receiving and making outgoing calls, while maintaining conversation secrecy. This circuit is useful when a single telephone line is to be shared by more members residing in different rooms/apartments.




     Normally, if one connects nine phones in parallel, ring signals are heard in all the nine telephones (it is also possible that the phones will not work due to higher load), and out of nine persons eight will find that the call is not for them. Further, one can overhear others’ conversation, which is not desirable. To overcome these problems, the circuit given here proves beneficial, as the ring is heard only in the desired extension, say, extension number ‘1’.

     For making use of this facility, the calling subscriber is required to initially dial the normal phone number of the called subscriber. When the call is established, no ring-back tone is heard by the calling party. The calling subscriber has then to press the asterik (*) button on the telephone to activate the tone mode (if the phone normally works in dial mode) and dial extension number, say, ‘1’, within 10 seconds. (In case the calling subscriber fails to dial the required extension number within 10 seconds, the line will be disconnected automatically.) Also, if the dialed extension phone is not lifted within 10 seconds, the ring-back tone will cease.

     The ring signal on the main phone line is detected by opto-coupler MCT-2E (IC1), which in turn activates the 10-second ‘on timer’, formed by IC2 (555), and energises relay RL10 (6V, 100-ohm, 2 C/O). One of the ‘N/O’ contacts of the relay has been used to connect +6V rail to the processing circuitry and the other has been used to provide 220-ohm loop resistance to deenergise the ringer relay in telephone exchange, to cut off the ring.

      When the caller dials the extension number (say, ‘1’) in tone mode, tone receiver CM8870 (IC3) outputs code ‘0001’, which is fed to the 4-bit BCD-to-10 line decimal decoder IC4 (CD4028). The output of IC4 at its output pin 14 (Q1) goes high and switches on the SCR (TH-1) and associated relay RL1. Relay RL1, in turn, connects, via its N/O contacts, the 50Hz extension ring signal, derived from the 230V AC mains, to the line of telephone ‘1’. This ring signal is available to telephone ‘1’ only, because half of the signal is blocked by diode D1 and DIAC1 (which do not conduct below 35 volts). As soon as phone ‘1’ is lifted, the ring current increases and voltage drop across R28 (220-ohm, 1/2W resistor) increases and operates opto-coupler IC5 (MCT-2E). This in turn resets timer IC2 causing: (a) interruption of the power supply for processing circuitry as well as the ring
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Tuesday, December 24, 2013

The antenna determines the shielding range of cellular phone jammer

The antenna determines the shielding range of cellular phone jammer. 
Should implement prevention unit is responsible, focused, ensuring safety "approach, in accordance with the principle of" who is in charge, who is responsible for the development of safe production responsibility system. Security work into the performance appraisal. A month to conduct a safety check, make a record, identify problems and timely rectification. Check the results and linked to the income of employees, through the specification and inspection to ensure the implementation of various rules and regulations. Pre-job of the salesperson, business training, security, confidentiality, and legal education, and pass the examination can be employed. To develop a cell phone store receipts, cash-carrying on the way the anti-robbery prevention and emergency response plans, and the familiar, once the incidence, rapid and effective processing solutions. The direction of cell phone jammer is decided by the antenna.
Security facility configuration, capital safety, electrical safety, fire safety management with reference to the business hall of Jiangsu Mobile Communication Co., Ltd. safety regulations "file execution. The information security manager responsible for the confidentiality of sales information: information security education on a regular basis, and stores the information security implementation of the supervision and inspection. For all types of business documents, internal company documents, work information, technical data and statistical analysis data, non-license led by the higher authorities, all employees shall not be privately available to any individual or entity shall not be privately copied, disk copy, or network transmission other ways out of the workplace. Systems Engineering in the case of stores people personnel changes, job transfers and permission to adjust the situation. The antenna and battery of cell phone jammer are the built in type.
The store manager shall promptly submit an application to the higher authorities, with the completion of work the application, close, permission to adjust the work in accordance with the requirements of the higher authorities. Business accepted members in their daily work involved in customers personal data, cost information, call list information must be kept strictly confidential and shall not be divulged. Customer data to strict management, the timely entry of the BOSS system. The raw data shall be properly kept on time and returned to the company. Place of business must be set within the computer power-on password may not be equipped with floppy drive must be disconnected from the network after work. Business computer, the timely replacement of the BOSS job number passwords should be based on the requirements of the higher authorities.
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Monday, December 23, 2013

Simple Electronic Code Lock

The circuit diagram of a simple electronic code lock is shown in figure. A 9-digit code number is used to operate the code lock.When power supply to the circuit is turned on, a positive pulse is applied to the RESET pin (pin 15) through capacitor C1. Thus, the first output terminal Q1 (pin 3) of the decade counter IC (CD 4017) will be high and all other outputs (Q2 to Q10) will be low. To shift the high state from Q1 to Q2, a positive pulse must be applied at the clock input terminal (pin 14) of IC1. This is possible only by pressing the push-to-on switch S1 momentarily.

Circuit diagram:
Simple-Electronic-Code-Lock-Circuit-Diagram
Simple Electronic Code Lock Circuit Diagram

On pressing switch S1, the high state shifts from Q1 to Q2. Now, to change the high state from Q2 to Q3, apply another positive pulse at pin 14, which is possible only by pressing switch S2. Similarly, the high state can be shifted up to the tenth output (Q10) by pressing the switches S1 through S9 sequentially in that order. When Q10 (pin 11) is high, transistor T1 conducts and energises relay RL1. The relay can be used to switch ‘on’ power to any electrical appliance. Diodes D1 through D9 are provided to prevent damage/malfunctioning of the IC when two switches corresponding to ‘high’ and ‘low’ output terminals are pressed simultaneously.

Capacitor C2 and resistor R3 are provided to prevent noise during switching action. witch S10 is used to reset the circuit manually. Switches S1 to S10 can be mounted on a keyboard panel, and any number or letter can be used to mark them. Switch S10 is also placed together with other switches so that any stranger trying to operate the lock frequently presses the switch S10, thereby resetting the circuit many times. Thus, he is never able to turn the relay ‘on’. If necessary, two or three switches can be connected in parallel with S10 and placed on the key-board panel for more safety. A 12V power supply is used for the circuit. The circuit is very simple and can be easily assembled on a general-purpose PCB. The code number can be easily changed by changing the connections to switches (S1 to S9).

Source : http://www.ecircuitslab.com/2012/01/simple-electronic-code-lock.html
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Sunday, December 22, 2013

Balancing LiPo Cells

Things change fast in the electronics world, and that’s also true for recharge- able batteries. The rate of development of new types of rechargeable batteries has been accelerated by the steadily increasing miniaturisation of electronic equipment. LiPo cells have conquered the market in a relatively short time. Their price and availability have now reached a level that makes them attractive for use in DIY circuits.

Balancing LiPo Cells Circuit diagram:

Balancing
Unlike its competitors Elektor Electronics has already published several articles about the advantages and disadvantages of LiPo batteries. One of the somewhat less well-known properties of this type of rechargeable battery is that the cells must be regularly ‘balanced’ if they are connected in series. This is because no two cells are exactly the same, and they may not all have the same temperature. For instance, consider a battery consisting of a block of three cells. In this case the outer cells will cool faster than the cell in the middle. Over the long term, the net result is that the cells will have different charge states. It is thus certainly possible for an individual cell to be excessively discharged even when the total voltage gives the impression that the battery is not fully discharged. That requires action – if only to prolong the useful life of the battery, since LiPo batteries are still not all that inexpensive.

One way to ensure that all of the cells have approximately the same charge state is limit the voltage of each cell to 4.1 V during charging. Most chargers switch over to a constant voltage when the voltage across the batter terminals is 4.2 V per cell. If we instead ensure that the maximum voltage of each cell is 4.1 V, the charger can always operate in constant-current mode.

When the voltage of a particular cell reaches 4.1 V, that cell can be discharged until its voltage is a bit less than 4.1 V. After a short while, all of the cells will have a voltage of 4.1 V, with each cell thus having approximately the same amount of charge. That means that the battery pack has been rebalanced.
The circuit (Figure 1) uses an IC that is actually designed for monitoring the supply voltage of a microcontroller circuit. The IC (IC1) normally ensures that the microcontroller receives an active-high reset signal whenever the supply voltage drops below 4.1 V. By contrast, the out-put goes low when the voltage is 4.1 V or higher. In this circuit the output is used to discharge a LiPo cell as soon as the voltage rises above 4.1 V.
When that happens, the push-pull output of IC1 goes low, which in turn causes transistor T1 to con-duct. A current of approximately 1 A then flows via resistor R1. LED D2 will also shine as a sign that the cell has reached a voltage of 4.1 V. The function of IC2 requires a bit of explanation. The circuit built around the four NAND gates extends the ‘low’ interval of the signal generated by IC1. That acts as a sort of hysteresis, in order to prevent IC1 from immediately switching off again when the voltage drops due the internal resistance of the cell and the resistance of the wiring between the cell and the circuit. The circuitry around IC2 extends the duration of the discharge pulse to at least 1 s.

Balancing w3

Figure 2 shows how several circuits of this type can be connected to a LiPo battery. Such batteries usually have a connector for a balancing device. If a suit-able connector is not available, you will have to open the battery pack and make your own connections for it. The figure also clearly shows that a separate circuit is necessary for each cell.
Author :Paul Goossens - Copyright : Elektor

Source:  http://www.ecircuitslab.com/2012/05/balancing-lipo-cells.html
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Saturday, December 21, 2013

This is why it is a good idea to get a universal gift

This is why it is a good idea to get a universal gift that all people will love. Here are some reasons why a booster is the perfect

present.
Shopping for a teen or a pre-teen can be an exceedingly difficult task. A person has to be updated on the latest gadgets and the hottest fashions. Instead of catering a gift to preconceived notions

of what teenagers might like, a person should buy a present based on what these teens will need. All young people use cell phones and the onset of smart phones has increased their prevalence. A

cell phone booster is a great gift because a teen is guaranteed to use it. Anything that allows them to talk and text for longer periods of time will keep them happy and satisfied for years to

come.
If a person has a businessman on his or her gift list, a cell phone booster is a terrific option. People who work in business rely on their phones in order to communicate with clients. There is

nothing more embarrassing than consistently dropping or missing calls. A cell phone booster will reduce the propensity for dropped telephone conversations. Any businessman will be thankful for a

device that allows them to conduct business in an easy and effective manner.
Shopping for ones parents can also be a perplexing experience. People often rely on flowers for their mothers and ties for their dads. A person should instead use some ingenuity and purchase a

cell phone booster for their parents. Although this technology has been around for a number of years, it will seem revolutionary to most parents. Many of them will marvel at the fact that they can

talk in any part of the house. This is a great present for parents that love to talk and communicate over the phone.
So for the upcoming holiday season, look for something that every person will love. Since most people have mobile phones, a cell phone booster is the ideal gift. They are terrific for any age group

and any demographic. So pick up a booster and reward the ones you love.If you have trouble talking on your cell due to a weak signal on the road, at home, or in the office, then a cell phone signal

booster can improve your reception and call quality. Do you need a booster for your weak signal? Many people report poor cell signals when traveling to different areas. Cellular boosters help you

by improving call quality and reducing dropped calls while being very easy to install.
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Friday, December 20, 2013

Build a Bridge Circuit Diagram With One Power Supply

This is simple Bridge Circuit Diagram With One Power Supply. For systems with only one power supply, two op amps act as instrumentation and buffer amps. The OPA111 AM buffers the reference mode of the bridge and applies that voltage to the instrumentation amps ref terminal. Output is taken between the amplifier outputs to exclude the fixed output offset. 

The additional op amp creates a bridge error of 2, where IB=bias current of op amp and R is the resistance of one leg of the bridge.

Bridge Circuit Diagram With One Power Supply

Build a Bridge Circuit Diagram With One Power Supply

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Thursday, December 19, 2013

Battery Charging Indicator

The Over-the-Top type of operational amplifier is ideal for use as a current sense for battery charger applications. The design described here can be used with chargers for rechargeable batteries (Lead/acid or NiCd etc). The 5V operating supply for the circuit is derived from the battery on charge. The circuit uses a sense resistor R8 to determine the value of current flowing in or out of the battery.

Battery Charger Display Circuit Diagram
Battery Charging Indicator Circuit Diagram

An LED output shows whether the battery is charging or discharging and an analogue output displays the battery charge or discharge current. The circuit can also be altered to shown different ranges of charging current to cater for higher capacity cells. IC1a and IC1b together with T1 and T2 form two current sources, which produce a voltage across R5. The voltage across R5 is proportional to the current through resistors R8 and R1 (for IC1a) or R8-R3 (for IC1b).


The current source formed by IC1a and T1 is active when the batteries are discharging and IC1b and T2 is active when the batteries are being charged. In each case the inactive opamp will have 0V at its output and the corresponding transistor will be switched off. IC1d amplifies the voltage across R5, which is proportional to the sense current. The component values given in the diagram produce an amplification factor or 10.

A sense current of 0.1 A will produce an output voltage of +1 V. The supply voltage to the circuit is +5 V so this will be the maximum value that the output can achieve. This corresponds to a maximum charge/discharge current of 0.5 A To display currents from 0 to 5.0 A, resistor R7 can be omitted to give IC1d a voltage gain of 1. Higher currents can be displayed by using a lower value of sense resistor R8. A DVM or analogue meter can be used at Vout to give a display of the charge/discharge current.

The constant current sources can only function correctly when the supply to the voltage regulator circuit (UBatt. e.g. 6V or 12V) is greater than the operating voltage of the opamps (+5 V). The supply voltage to the LT1639 can be in the range of +3 V and +44V and voltages up to 40V over the supply voltage are acceptable at the inputs to the opamp. IC1c controls the charging/discharging LED output. The inputs to this opamp are connected to the outputs of the current source opamps and its output goes high when the battery is being charged and low when it is discharging.

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Wednesday, December 18, 2013

Simple Knight Rider lights Circuit for model cars

This simple circuit drives 6 LEDs in Knight Rider scanner mode. Power consumption depends mainly on the type of LEDs used if you use a 7555 (555 CMOS version).


Simple Knight Rider lights Circuit

Simple Knight Rider lights Circuit for model cars


Note
That VDD and GND for the ICs are not shown in the circuit drawing.

Pin-outs:
(7)555 4017
1 GND 1 Q5 9 Q8
2 TRIGGER 2 Q1 10 Q4
3 OUTPUT 3 Q0 11 Q9
4 RESET 4 Q2 12 CO
5 CONTROL VOLTAGE 5 Q6 13 NOT ENABLE
6 THRESHOLD 6 Q7 14 CLK
7 DISCHARGE 7 Q3 15 RESET
8 VDD 8 GND 16 VDD
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Telephone In Use Indicator

This circuit will illuminate a LED if one of your telephones is in use. It should work in all countries (Including UK) that have a standing line voltage above 48 Volts DC. Please note that it is illegal to make a physical permanent connection to your telephone line in some countries (this includes the UK and Ireland). If building this circuit it is advisable to use a plugin cord so that the unit can be unplugged should a fault occur. If in doubt consult either your telephone or cable operator.

If all extension phones are on-hook and the line voltage is around 48 V, Q1 will conduct thus effectively shorting the gate of Q2 to its source, so it will be off and the LED will be disabled. Lifting the handset of any phone on the line causes the line voltage to drop to 5-15 V. The gate voltage of Q1, equal to some 6% of the line voltage, will then be too low and Q1 will be turned off. So Q2s gate is now biased at approximately 1/2 of the line voltage, Q2 turns on and the LED indicates that the line is in use. The circuit itself is practically invisible to the other telephone devices using the same line. LED1 must be low-current and its current-limiting resistor must be 2k2 or more. The other components ideal values may vary slightly, depending on the local telephone line parameters. The circuit is powered off the telephone line. If other types of MOSFETs are used, the 500k trimmer can be adjusted to ensure that Q1 is biased fully on while the line is not in use (LED1 off), and vice versa.

Telephone In-Use Indicator Circuit Diagram


Telephone-In-Use-Indicator circuit diagram 
If Q2 is not a BS108 but some other 200 V MOSFET with a higher G-S threshold voltage, it might be necessary to increase the value of the lower (or decrease the value of the upper) one of the two resistors connected to the gate of Q2. Plain (bipolar junction) transistors can be used instead and the circuit also works fine. But the resistor values are then much lower - letting ten times more microamps of current pass through while the line is not in use, and even this MOSFET design still could not meet formal minimum on-hook DC resistance specifications. Both prototypes PCBs were 4x1 cm. The current-limiting resistor for LED1 is 2k2 in both cases. DO NOT ground any of the leads or conducting surfaces in this circuit. A more reliable design would also include some kind of over-voltage protection etc.

Warning:

In their normal course of operation, telephone lines can deliver life-threatening voltages! Do not attempt to build any of the circuits/projects unless you have the expertise, skill and concentration that will help you avoid an injury. There are also legal aspects and consequences of connecting things to telephone lines, which vary from country to country. Keep away from telephone lines during a lightning storm!


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Tuesday, December 17, 2013

Automatic TV Lighting Switch

The author is the happy owner of a television set with built-in Ambilight lighting in the living room. Unfortunately, the television set in  the bedroom lacks this feature. To make up for this, the author attached a small lamp to the wall to provide background lighting, This makes  watching television a good deal more enjoyable, but it ’s  not the ideal solution. Although the TV set can be  switched off with the remote  control, you still have to get out of bed to switch off the lamp.

Automatic TV Lighting Switch Circuit diagram:

Automatic TV Lighting Switch-Circuit-Diagram



Consequently, the author devised this automatic lighting switch that switches the background light on and off along with the T V set. The entire circuit is fitted in series with the mains cable of the TV set, so there’s no need to tinker with the set. It works as follows: R1 senses  the current drawn by the TV  set. It has a maximum value  of 50 mA in standby mode,  rising  to around   500 m A  when  the  set  is  operating. The voltage across R1 is limited by D5 during negative  half- cycles  and  by  D1– D4  during positive half-cycles.  T he  voltage  across  these  four diodes charges capacitor C1 via D6 during positive  half-cycles. This voltage drives the internal LED of solid-state switch TRI1 via R2, which causes the internal triac to conduct and pass the mains voltage to the lamp.   Diode D7 is not absolutely necessary, but  it is recommended because the LED in the  solid-state switch is not especially robust  and cannot handle reverse polarisation. Fuse  F1 protects the solid-state switch against  overloads. T he  value  of  use d  here  (10 Ω)  for  resistor R1 works nicely with an 82-cm (32 inch)  LCD screen.

With smaller sets having lower  power consumption, the value of R1 can be  increased to 22 or 33 Ω, in which case you  should use a 3-watt type. Avoid using an  excessively high resistance, as otherwise TRI1 will switch on when the TV set is in standby mode.  Some TV sets have a half-wave rectifier in the  power supply, which places an unbalanced  load on the AC power outlet. If the set only  draws current on negative half-cycles, the cir-cuit won’t work properly. In countries with  reversible AC power plugs you can correct  the problem by simply reversing the plug. Compared with normal triacs, optically cou-pled solid-state relays have poor resistance  to high switch-on currents (inrush currents).

For this reason, you should be careful with  older-model TV sets with picture tubes (due  to demagnetisation circuits). If the relay fails,  it usually fails shorted, with the result that the TV background light remains on all the time. If you build this circuit on a piece of perf-board, you must remove all the copper next  to conductors and components carrying  mains voltage. Use PCB terminal blocks with a spacing of 7.5 mm. This way the separation between the connections on the solder  side will also be 3 mm. If you fit the entire  arrangement as a Class II device, all parts of  the circuit at mains potential must have a  separation of at least 6 mm from any metal  enclosure or electrically conductive exterior  parts that can be touched.

Author :Piet Germing - Copyright : Elektor

Source :  http://www.ecircuitslab.com/2012/03/automatic-tv-lighting-switch.html
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