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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Portable Microphone Preamplifier

High headroom input circuitry, 9V Battery operation

This circuit is mainly intended to provide common home stereo amplifiers with a microphone input. The battery supply is a good compromise: in this manner the input circuit is free from mains low frequency hum pick-up and connection to the amplifier is more simple, due to the absence of mains cable and power supply. Using a stereo microphone the circuit must be doubled. In this case, two separate level controls are better than a dual-ganged stereo potentiometer. Low current drawing (about 2mA) ensures a long battery life.

Circuit Operation:

The circuit is based on a low noise, high gain two stage PNP and NPN transistor amplifier, using DC negative feedback through R6 to stabilize the working conditions quite precisely. Output level is attenuated by P1 but, at the same time, the stage gain is lowered due to the increased value of R5. This unusual connection of P1, helps in obtaining a high headroom input, allowing to cope with a wide range of input sources (0.2 to 200mV RMS for 1V RMS output).

Portable Microphone Preamplifier Circuit diagram:

Parts:
P1 = 2.2K
R1 = 100K
R2 = 100K
R3 = 100K
R4 = 8.2K
R5 = 68R
R6 = 6.8K
R7 = 1K
R8 = 1K
R9 = 150R
C1 = 1uF-63V
C2 = 100uF-25V
C3 = 100uF-25V
C4 = 100uF-25V
C5 = 22uF-25V
Q1 = BC560
Q2 = BC550

Notes:

• Harmonic distortion is about 0.1% @ 1V RMS output (all frequencies).
• Maximum input voltage (level control cursor set at maximum) = 25mV RMS
• Maximum input voltage (level control cursor set at center position) = 200mV RMS
• Enclosing the circuit in a metal case is highly recommended.
• Simply connect the output of this device to the Aux input of your amplifier through screened cable and suitable connectors.

Source :  http://www.ecircuitslab.com/2011/06/portable-microphone-preamplifier.html

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Solar Panel Voltage Regulator

Our energy-hungry and environmentally aware society has been slow to make good use of the suns "free" power. But now its finally taking off. Using the suns heat directly, for cooking and other applications, is already a common and popular technology in countries that have good weather. Hot-water panels are nowadays used in many parts of the world, in combination with a gas or electric powered water heater to help out when the weather doesnt help.

But at the same time, electric solar panels are still expensive, justifying their use only as a novelty, or in locations where little power is needed, and bringing in commercial power would be even more expensive. A solar electric power system needs panels for generation, batteries for storage, a regulator to keep the batteries within a safe operating range, and in some cases a power converter for AC output.

For those who need to set up a few panels for a summer cottage, a boat, a remote mountaintop installation, or whatever, Im herewith providing a version of the regulator circuit that I have used in a lot of such installations. Such a solar panel regulator should perform at least two operations: The obvious one is protecting the battery from overcharge at times of strong sun and little consumption, and the other is protecting it from excessive discharge in bad weather conditions. Both overcharge and deep discharge are harmful to a battery.

For regulating a solar panels output, there are several possible ways. A linear series regulator can be used, but has the disadvantage of causing some voltage drop and having some internal power consumption at times when the sun is weak and the load is heavy. Its much better to use a shunt regulator, which is inactive at such times, and springs to life only when there is excess energy. For this reason, most solar panel regulators use the shunt scheme, the one presented here being no exception.

But such shunt regulators come in two flavors: Most commercial units are ON-OFF regulators. That means, they have a simple switch device, most often a transistor or MOSFET, sometimes even just a relay, that stays off until the battery reaches over voltage, and then switches in, shorting out the panel until the battery voltage has dropped off. Then the full panel current is switched on again. The only advantage of this method is thats cheap. The power switch operates with very low power dissipation, allowing a small, low cost construction.

But the disadvantages of this system are major: The voltage output is all the time fluctuating between about 13 and 14.5V. The battery is cycling between getting overcharge and having to deliver all the load current, which severely reduces the batterys lifetime. And in the event of battery disconnection or failure, the regulator cycles quickly, applying pulses of full panel voltage to the output, which can destroy sensitive equipment powered by the system!

The circuit presented here uses linear shunt regulation. Simply spoken, it burns off all excess energy from the panel, keeping output voltage constant. At times when the solar panel output is equal or greater than the load, and the battery is fully charged, the load gets its power from the panel, while the battery rests at full charge. Five years battery lifetime are entirely normal with this system, while the same batteries last only two to three years when used with pulsing regulators!

The second responsibility of the regulator is watching over the battery voltage, and dropping off the load when the battery gets discharged too much. Lead batteries are severely damaged by deep discharges, so its far preferable to drop off the load, then to have the battery die in a bad weather spell. This regulator is designed for 12V systems employing panels of up to 7A total current, and loads of not over 20A. It can be easily modified for greater currents.

U1A compares an adjustable sample of the present battery voltage to a 5V reference from a highly stable source. According to the result, it controls the power transistors Q1 and Q2, which shunt off the excess power generation from the panel. A diode (D1) avoids battery voltage to go back to the panel under no-light condition. To avoid imprecise voltage control due to varying diode drop, the sample is taken from the battery side, even if this means a very small power waste.

The power resistors R1 and R2 are dimensioned in such a way that under maximum shunting, these resistors will dissipate almost all power (about 100W total), leaving the transistors running cool. The highest dissipation in the transistors happens when the regulator is dissipating half of the panel output; in this case, each transistor will dissipate about 12W.

U1B is a Schmitt trigger that compares the battery voltage to the same stable reference of the other section, but for another purpose: It controls the load switch Q3. This circuit will disconnect the load if the battery gets close to deep discharge, and reconnect it only when recharge is well underway. The negative side of the load is switched, simply because N-channel MOSFETs are much cheaper and better than P-channel ones.

Component notes:

D1 can be any diode that can safely survive the panels current. If the panel has a very low voltage output (less than 33 cells in series), it is an advantage to employ a Schottky diode in this place. Q1 and Q2 are common power Darlington transistors. They need to be heatsinked for safe long-term operation at the 12 Watt dissipation level. Thats easy enough to do, but many newcomers misjudge how much thermal resistance is introduced by a mica insulator! Plan on 1K/W thermal resistance inside each transistor, two times as much in the insulator (if you use any), and 370K safe junction temperature. For typical environmental conditions, this makes you need a heatsink having a thermal resistance of about 1.3K/W. If it is larger, you get more safety margin.

R1 and R2 will have to be made by combining a number of power resistors in parallel. Yes, you need to make two resistor arrays of 4 Ohm, 80W each! This 80W figure includes a reasonable safety margin. These resistors will produce a lot of heat, and you may cook your coffee on them! Be sure to mount them in such a way that they have lots of ventilation, and that the heat from them will not reach the other components. R3 and R4 may to have be built from parallel combinations too, because of the low value of only 0.15 Ohm.

U2 is a voltage reference IC. You cannot replace it by a standard Zener diode! Zeners are much too unstable! If you cant find this chip locally, you may use the ubiquitous 7805 regulator instead, but the power drain from the battery will be higher. In this case, of course you dont need R8, but you would need a 1uF capacitor at the 7805 output. Q3 is a power MOSFET that has a very low Rds(on). You may use a different one, provided that it has a resistance thats low enough for your application. You may use several in parallel. The one I used has low loss even at loads of 20A, and can handle much more!

Calibration:

Once the circuit is assembled, calibration is quite easy. Connect the panel, leave the battery and load disconnected. With a nice sun on the panel, adjust RV1 for the desired voltage at the battery output. I recommend 13.8V for sealed batteries, and 14 to 14.2V for open cell ones, to which water can be added if necessary.

Now you need either a variable power supply connected to the battery lines, or some kind of variable load. You may also use your panel as variable power supply, by tilting it away from the sun while a fixed load is connected to the battery lines. The idea is to adjust the voltage at the battery lines to the desired shut-off value (I recommend 11.5V), and then move RV2 until Q3 shuts off, as indicated by a voltmeter across the load output, a 12V light bulb, or whatever you can use to detect it.

After Q3 has shut off, increase the voltage across the battery lines and see at which level Q3 switches on again. This should happen above 12.6 and below 13.4 V. You may have to retouch RV2 and look for a compromise between ON and OFF voltages. If your components are not too much out of value, then both potentiometers should have ended up reasonably close to the center position.

Using more panels:

You can use this regulator for larger installations. Simply add one group like R1-Q1-R3 for each additional 3.5A panel, and use a diode for D1 that handles the total current. Remember that large diodes need heat sinks! U1A can drive at least 8 such transistors. If you intend to build a really large system, you may want to add an emitter follower between U1A and the power transistors. If you need to handle large load currents, you can place as many MOSFETs in parallel as you need. There is no practical driving limitation in this case. [via]

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Build a PIC Security System Dials Your Cell Phone Circuit Diagram

This is a simple PIC Security System Dials Your Cell Phone Circuit Diagram. Do-it-yourself phone dialer security system calls your cell phone, office etc. whenever a door or window is opened, or panic button is pressed. Great Home Alarm.

PIC Security System Dials Your Cell Phone Circuit Diagram

The circuit consists of a small PIC microcontroller, assembly program, and a few other parts to detect a switch closure from an open door, window, or manual push button and then dial the cell phone number, and transmit a steady tone to indicate the source of the call. The circuit uses the pulse dialing system to interrupt the line connection a number of times to indicate each digit. Pulse dialing (the oldest form of dialing) works by actually disconnecting or "hanging up" the phone line a number of times to indicate each digit. For example, the digit "5" would be dialed by disconnecting and reconnecting the line 5 times in short intervals of about 100mS. There is about a 1 second pause (with the line connected) between each digit. The timing is not critical and I was able to dial 411 and connect to the local information service just using a momentary push button switch in series with the phone line.

Circuit Operation:
In operation, the switch closure is detected on pin 7 of the processor which activates the reed relay and takes the line off-hook for 3 seconds to establish the dial tone. The processor then dials the number by opening and closing the relay a number of times for each digit. When dialing is complete, the processor waits 3 seconds and then transmits a steady tone of about 300Hz for 30 seconds through the modem transformer. The call is then terminated and the processor waits for the switch to open before resetting.

Design Considerations:

The PIC16F628 (18 pin) processor was selected because I had a few on hand and my homemade hardware programmer only accepts 18 pin devices. A smaller 8 pin device could have been used since only three I/O lines are needed, but the difference in cost is only about $1.50. One of the I/O lines (RA5) is used for programming and is always an input, but can used as a functional input so the switch closure could be detected on this line thus eliminating the need for one pullup resistor. But I elected to use 3 consecutive I/O pins (7,8,9) of the 8 bit port B and leave RA5 pulled up with a extra 10K resistor.

The output pins (8,9) that drive the relay and transformer are limited to 25mA of current each, so an extra transistor (2N2222A) was needed to supply additional current to the relay coil. The transformer resistance is around 100 ohms, so an additional 330 ohm resistor was added in series with pin 9 to limit the transformer current to around 10mA. An LED indicator and 330 ohm resistor were used on pin 8 to observe the dialing activity and indicate the line status. Several of the parts (relay, transformer and blocking capacitor) were obtained from an old 56K modem card.

The schematic shows a 47uF / 50 volt non-polarized capacitor used to block DC current to the transformer, however a regular polarized 50uF cap could be used if correct phone line polarity is observed. The modem was probably designed to work with unknown polarities at different locations, so a non-polarized cap was used. Its possible the cap and 470 ohm resistor can be replaced with a single resistor in series with the line to set the "off hook" line current to around 20mA. This may cause partial saturation of the transformer and reduced audio level, but might work well enough.

The power supply voltage is not critical and a 4.5 volt supply from three AA batteries should work. Or a switching type regulated 5 volt wall transformer can be used. The problem is insuring the relay gets enough voltage to operate. The rest of the circuit should run on reduced voltage. I used a 4.2 volt cell phone charger that worked well.

 Softwre

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cell phone jammer can be used in many different locations

cell phone jammer can be used in many different locations.
Gome relevant responsible person said, 3C products as the countrys largest retail outlets, Gome will continue to play a channel edge, constantly driving down the price of smart phones, and promote the rapid popularization of smart phones to achieve. The above is a brief analysis of the entire smart phone market in 2011 and the subsequent trend, in fact, the contents of the trend report, we generally can be drawn about the several conclusions: the future of the smart phone market in the short term there will be a flowers dispute put state; 2, smart phones in terms of functionality, integration and user-friendly development will eventually lead to the complete detachment of the interdependence between smartphones and traditional PCs. Of course, for the different locations, different kinds of cell phone jammer are required.
The role played by traditional 3C stores in the future smartphone sales will be increasing; the future of smart phones is the mobile phone development. Survey of Chinese mobile phone. 2008 Marketing Professional of the Yuzhong District Teaching Department. Abstract: From 1998, China formally enter the mobile phone production date from 2003, won the big half of the peak in 2004, falling about 30% of the market share, now clinging to the way bittersweet, domestic mobile phone. In a few short years, China has become the worlds largest mobile phone users. Process along the way, the domestic mobile phone encountered a setback, but also saw the opportunity. In this paper, and international brand mobile phone competition in the domestic mobile phone to find the advantage of domestic mobile phone, also found that the challenges and opportunities to come. cell phone jammer can own different indices and parameters.
According to statistics, in 1996 made the first GSM mobile phone available, starting later than the foreign brands a decade, from the development point of view of the market share of domestic brands is almost zero in 1997, officially started in 1998, 1999 13 million units, accounting for 5% of the national production; 2000, 4.4 million, accounting for 6.4%; 10.48 million in 2001, accounting for 12.3%; has been a breakthrough fierce fighting in 2002 reached 14.97 million per month from 1-10 sales of 14.45 million, of which exports 330,000, accounted for 19.8 percent of the national total production in the domestic market share has reached 33 percent, an increase of 11 percentage points over the same period last year. cell phone jammer should have different performances and functions.
To the four indicators, the product quality of the phone (referred to as quality), the appearance of the product of the mobile phone (referred to as appearance), the price of the phone (referred to as price), and mobile phone products (referred to as functions) for the investigation of an index, and the quality, appearance , functional three-level indicators are divided into a number of secondary indicators.

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Telephone Tapping Indicator

This simple circuit can indicate a misuse or tapping of Telephone line through a loud alarm. The circuit is too simple and can be easily assembled on a common PCB. Line voltage of Telephone lines is around 48 volts DC in the On hook state. When the handset is lifted, this voltage reduces to 12 volt DC. This change in voltage level is used to activate the circuit.When the switch S1 is closed, circuit becomes active and the telephone enters into the armed state.

The high volt DC from the telephone line passes through R1 and VR1 and bias T1 into conduction. As a result, the collector of T1 goes to ground potential to inhibit T2 from conduction. Buzzer and LED thus remain off. When the handset is lifted, the DC voltage from the telephone lines drops to 12 volts. This turns off T1 and T2 conducts. Buzzer beeps and LED lights indicating that the telephone is using.

Telephone Tapping Indicator Circuit

Setting
Connect the circuit to Telephone lines using a telephone plug. The free socket of the telephone or Caller ID can be used. Close S1 and adjust VR1 till buzzer stops beeping. Lift the handset. Buzzer should sound. Otherwise, just adjust VR1 till buzzer beeps.

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mobile phone jammer is installed in the hallway of every floor

 mobile phone jammer is installed in the hallway of every floor.
Sun at age 16 moved to the United States, California, and the learning of the University of California at Berkeley, majoring in Economics. School, where he invented a pocket translator, and applied for a patent, after the price of one million U.S. dollars, to sell translator Sharp company. Later created the Unison, the company is now for all Kyocera. Sun back to the Japanese banking software company, founded in 1981, the goal is to popularize computer knowledge to the Japanese. Early development of the Internet, Sun to his unique vision and courage to invest a large number of successful Internet startups including Yhaoo, ETrade, Softbank deservedly stood in the forefront of the Internet revolution. Source: to Pconline keep abreast 0 mobile phone to see news in 2001, Softbank opening of the Yahoo. BB business broadband ADSL services to subscribers in Japan. Moreover, installation of intelligent management system of school mobile phone jammer doesn’t shield the cell phone signal all day.Existing Industrial Park, 13, 30 overseas factories and manufacturing base, and eight overseas design center, 58800, marketing outlets. Huawei - Huawei is one of the global communications industry, a leading supplier of communications equipment R & D, production, marketing and service for customers around the world in the field of telecommunications network equipment to provide innovative, customized, services and solutions to achieve the customers potential for growth, sustained long-term value for our customers. As of October 2005, Huawei in the international market covering over 90 countries and regions in the worlds top 50 operators, 22 the use of Huaweis products and services. It is the examination room shielding of imported mobile phone jammer .
The biggest bright spot of the mobile advertising mobile phones and advertising combine to form a tripartite benefit of customers, businesses and carriers situation. 1.3 Analysis of mobile advertising -2 1.3.1 - Changsha Aeronautical Vocational and Technical College thesis a mobile advertising overall situation of the mobile advertising market analysis with the development of mobile communication technology, the 3G service model continues to become clear, mobile service model derived into innovation The change of phase. With mobile phones, known as the "media" and the term "mobile advertising" began to frequent exposure. U.S. market research firm Visiongains market report said, three years later, the U.S. and European mobile phone advertising market will reach about $ 1 billion. It is the specific school imported mobile phone jammer .
The problems of mobile advertising and defective defective mobile advertising: First, the boycott of mobile phone users on the ad. The current development of mobile advertising, due to the lack of relevant laws and regulations, advertising operators without mobile phone users any license on any advertising, -8 - 3 mobile advertising application and operation of Changsha Aeronautical Vocational and Technical College Thesis mode analysis is commonplace.

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