The main body of cell phone jammer should be installed on the top

 Personality, social factors and individual background variables on the mobile phone text messages have a certain psychological predictors. Personality, social factors and individual psychological background variables through SMS mobile phone text messages as an intermediary variables on the use of the Indirect impact. While the extraversion personality and sense of responsibility can also be used directly to predict behavior of mobile phone text messages.  Study were 475 valid questionnaires, which have cell phones, the number of people using SMS 81.5%. And consistent with previous findings, gender, whether to use SMS, SMS cost ratio and the number of SMS sent in did not show significant differences in the impact of family origin is an important factor in the use of SMS. To the individual background variables, social factors and Big Five personality as a predictor variable, the need to make friends as the dependent variable for multiple regression analysis, the results can be found not found the variable into the regression equation, indicating that these variables can not predict the respondents from the phone SMS in the need to make friends. The personal, social, and psychological factors can not only directly affect the behavior of SMS use, but also indirectly through the psychological impact of mobile phone SMS text messaging usage behavior. The more visualized explanation is that the requestor is serially connected with the power end of cell phone jammer . In addition, the various dimensions of social support through the impact on the understanding of the prevalence of mobile phone text messages, SMS can also affect the adoption, but the indirect effects of several sub-dimensions there are also negative, temporarily unable to identify its overall impact. SMS students and levels of consumption structure is relatively simple, the impact SMS consumption, the main factor is price, followed by the SMS unique expression. Students send SMSs main target is family and friends, mainly for blessings class, the purpose is to increase contact and exchange feelings, access to information. SMS mobile phone costs account for the proportion of expenditure generally below 50%, generally in the week to send the number 50 below. The main body of cell phone jammer should be installed on the top inside the box with the antenna coming out of the box body.
Nokias highly trained staff has been reflected in the market. From the service side, the customer believes that Nokia service personnel trained, professional and standards. However, we believe that Nokias personnel training system although very advanced, but which lack a very important factor, that is humane. The results from the previous market research, we learned that the customer is usually very reliable service with Motorola phones Nokia, but Nokia mobile phone service although professional but not much expression. Instead of Motorola employees in the "smile" of the relative place. Nokia Corporation (Nokia Corporation NYSE: NOK) is a multinational mobile communications products, headquartered in Finland. In the mobile phone market, Nokia has for years occupied the market share position.

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Universal Battery Charger Based on LM317

This universal battery charger is based on LM317 and has an adjustable regulated output voltage and also has an adjustable constant-current charging circuit that makes it suitable to use for charging most NiCad batteries and some other types of batteries . This LM317 universal battery charger can charge a single cell or a number of series-connected cells up to a maximum voltage of 18 V.

This universal battery charger circuit use just some common electronic components like LM317 regulator , operational amplifier and some 2n3055 power transistors .2n3055 power transistors Q1 and Q2 are connected as series regulators to control the battery chargers out¬put voltage and charge-current rate. The LM317 used as an adjustable voltage regulator supplies the drive signal to the bases of power transistors Q1 and Q2.

By turning the potentiometer R9 the output-voltage level will be modified. A current-sampling resistor, R8 (a 0.1-fi, 5-W unit), connected between the negative output lead and circuit ground.As the charging voltage across the battery begins to drop, the current through R8 decreases , then the voltage feeding pin 5 of U3 decreases, and the comparator output follows, turning Q3 back off, which completes the signals circular path to regulate the batterys charging current. The charging current can be set by adjusting R10 for the desired current.

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Stereo Power Amplifier Circuit based on BA5417

BA5417 is a stereo amplifier IC with a lot of good features like thermal shut down, standby function, soft clipping, wide operating voltage range etc. The IC can deliver 5W per channel into 4 ohm loud speakers at 12V DC supply voltage. The BA5417 has excellent sound quality and low THD (total harmonic distortion) around 0.1% at F=1kHz; Pout=0.5W.

Stereo Power Amplifier  Circuit diagram :

Setup and working of this stereo power amplifier circuit is somewhat similar to the BA5406 based stereo amplifier circuit published previously. C10 and C11 are DC decoupling capacitors which block any DC level present in the input signals. C2 and C6 couples the amplifiers left and right power outputs to the corresponding loud speakers. C1 and C5 are bootstrap capacitors.

Bootstrapping is a method in which a portion of the amplifiers is taken and applied to the input. The prime objective of bootstrapping is to improve the input impedance. Networks R1,C3 and R2,C7 are meant for improving the high frequency stability of the circuit. C4 is the power supply filter capacitor. S1 is the standby switch. C8 is a filter capacitor. R3 and R4 sets the gain of the left and right channels of the amplifier in conjunction with the 39K internal feedback resistors.

Note :

• Supply voltage range of BA5417 is from 6 to 15V DC.
• The recommended supply voltage for this circuit is 12V DC.
• The power supply must be well regulated and filtered.
• BA5417 requires a heatsink.
• The circuit can be assembled on a perf board without much degradation in performance.

Source : http://www.ecircuitslab.com/2012/07/stereo-power-amplifier-circuit-based-on.html

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Power On Indicator

Some types of electronic equipment do  not provide any indication that they are  actually on when they are switched on.  This situation can occur when the back-light of a display is switched off. In addition, the otherwise mandatory mains  power  indicator  is  not  required  with  equipment  that  consumes  less  than  10 watts. As a result, you can easily forget  to switch off such equipment. If you want  to know whether equipment is still drawing power from the mains, or if you want  to have an indication that the equipment  is switched on without having to modify the equipment, this circuit provides a solution. 

One way to detect AC power current and  generate a reasonably constant voltage  independent of the load is to connect a  string of diodes wired in reverse parallel in series with one of the AC supply  leads. Here we selected diodes rated  at 6 A that can handle a non-repetitive  peak current of 200 A. The peak current  rating is important in connection with  switch-on  currents.  An  advantage  of  the selected diodes is that their voltage  drop increases at high currents (to 1.2 V  at 6 A). This means that you can roughly  estimate the power consumption from  the brightness of the LED (at very low  power levels). The voltage across the diodes serves as  the supply voltage for the LED driver. To  increase the sensitivity of the circuit, a  cascade circuit (voltage doubler) consisting of C1, D7, D8 and C2 is used to double  the voltage from D1–D6. Another benefit  of this arrangement is that both halve- waves of the AC current are used. We use  Schottky diodes in the cascade circuit to  minimise the voltage losses.

Circuit diagram :

Power On Indicator Circuit Diagram

 

The LED driver is designed to operate the LED  in blinking mode. This increases the amount  of current that can flow though the LED when  it is on, so the brightness is adequate even  with small loads. We chose a duty cycle of pproximately 5 seconds off and 0.5 second  on. If we assume a current of 2 mA for good  brightness with a low-current LED and we can  tolerate a 1-V drop in the supply voltage, the  smoothing capacitor (C2) must have a value of  1000 µF. We use an astable multivibrator built around two transistors to implement a  high-efficiency LED flasher. It is dimensioned to minimise the drive current of  the transistors. The average current consumption is approximately 0.5 mA with a  supply voltage of 3 V (2.7 mA when the  LED is on; 0.2 mA when it is off). C4 and  R4 determine the on time of the LED (0.5  to 0.6 s, depending on the supply volt-age). The LED off time is determined by  C3 and R3 and is slightly less than 5 seconds. The theoretical value is R × C × ln2,  but the actual value differs slightly due to  the low supply voltage and the selected  component values.

 

Diodes D1-D6 do not have to be special  high-voltage diodes; the reverse volt-age is only a couple of volts here due  the reverse-parallel arrangement. This  voltage drop is negligible compared to  the value of the mains voltage. The only  thing you have to pay attention to is the  maximum load. Diodes with a higher  current rating must be used above 1 kW.  In addition, the diodes may require cool-ing at such high power levels.  Measurements on D1–D6 indicate that  the voltage drop across each diode is  approximately 0.4 V at a current of 1 mA.  Our aim was to have the circuit give a  reasonable indication at current levels  of 1 mA and higher, and we succeeded  nicely. However, it is essential to use a  good low-current LED.

 

Caution: the entire circuit is at AC power potential. Never work on the circuit with the mains cable plugged in. The  best enclosure for the circuit is a small,  translucent box with the same colour as  the LED. Use reliable strain reliefs for the  mains cables entering and leaving the  box (connected to a junction box, for  example). The LED insulation does not  meet the requirements of any defined insulation class, so it must be fitted such that it  cannot be touched, which means it cannot  protrude from the enclosure. 

http://www.ecircuitslab.com

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Universal Battery Charger Based on LM317

This universal battery charger is based on LM317 and has an adjustable regulated output voltage and also has an adjustable constant-current charging circuit that makes it suitable to use for charging most NiCad batteries and some other types of batteries . This LM317 universal battery charger can charge a single cell or a number of series-connected cells up to a maximum voltage of 18 V.

This universal battery charger circuit use just some common electronic components like LM317 regulator , operational amplifier and some 2n3055 power transistors .2n3055 power transistors Q1 and Q2 are connected as series regulators to control the battery chargers out¬put voltage and charge-current rate. The LM317 used as an adjustable voltage regulator supplies the drive signal to the bases of power transistors Q1 and Q2.

By turning the potentiometer R9 the output-voltage level will be modified. A current-sampling resistor, R8 (a 0.1-fi, 5-W unit), connected between the negative output lead and circuit ground.As the charging voltage across the battery begins to drop, the current through R8 decreases , then the voltage feeding pin 5 of U3 decreases, and the comparator output follows, turning Q3 back off, which completes the signals circular path to regulate the batterys charging current. The charging current can be set by adjusting R10 for the desired current.

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LED Light Bulbs Save Energy on Mysore Palace Board

As the first step towards the conservation of energy, The Mysore Palace Board began working with the replacement of equipment outside the halls of the palace (along the tracks and walk to the door) with Eco-LED (light emitting diode of light). 12 volt led lights will be enough.

As part of the first stage of labor, 685 units were replaced with LED lights to a golden color, as desired by the Council of the palace.

The contract was awarded to a man named S. Mysore Nagaraj, CEO of green light Trishul, Bangalore.

Star of Mysore Nagaraj said the Rs 77 lakh contract for the replacement of more than 3,000 lights on the Palace Square, which will be implemented in five phases. "Each LED unit is guaranteed for 50,000 hours," said Nagaraj and added, "the unit cost of Rs 30 watts. 14 000 and 60 watt unit cost of Rs 28000th service and replacement guarantee has been issued for five years. "

Nagaraj said the LED lights with LED other contractors that submitted bids were reviewed by representatives of the Board of Directors of NIE engineers and technicians Palace before awarding the contract. They insisted on using a light outside the Palace of Golden Hue.

".. The main advantage of energy saving LED lamps produce more light on the production of electricity used for LED bulbs are a great power, consumes less electricity," said Nagaraj, adding LED lights have the stabilizer circuit voltage , which takes the voltage range of 90 to 270 volts. They are also recyclable, he said.

Related items:12 volt led light bulbs.12 volt led light bulb

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Quick on board Junction Tester

Short circuits or broken pcb tracks can be easily recognized by means of a Multimeter, but this tool can give wrong results when testing the efficiency of a transistor or diode, unless the device under test is unsoldered and removed from the pcb.

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