Showing posts with label in. Show all posts
Showing posts with label in. Show all posts
Thursday, January 9, 2014
1900 1990MHz is also contained in the working frequency of cell phone jammer
1900~1990MHz is also contained in the working frequency of cell phone jammer .
Brand and customer base better. Earlier from the Chinese network is one of the manufacturers to enter online, through continuous development, has formed a good brand and user base. As of the end of March 2009, page views from the Chinese network has reached 300 million times / day. In addition, from the Chinese networks literature as a grand site, as Shanda comprehensive line of wireless entertainment business, one in human resources, product integration operations (such as the original literature into online games, etc.) also has a large advantage . Chinese online (www.ChineseAll.com) was established in 2000 at Tsinghua University, is one of Chinas Internet publishing pioneer, leading to the most legitimate digital content broadcaster. At present, the Chinese online products or services related to educational institutions, government agencies, public consumption, in various market development in a leading position.
Chinese online product content, copyright and other aspects of operations and customer base are more advantages, mainly in the following points: rich, extensive resources: Chinese online digital rights in China earlier one operating company, has accumulated a rich content resources, in addition to the Internet with the original literature, but also a broad range of primary and secondary education for users, courseware and other content resources, and have literature classes, art classes, childrens class, economics and management, integrated classes, education classes, lifestyle, tools and other literary works. This type of cell phone jammer can work as long as the antenna is collectively connected and the power supply is switched on.
Resources are more extensive content partners: Chinese online now with publishers, writers, original site, the book established the upper range of content partnerships, at present, with more than 400 publishers, more than 8,000 well-known writer, mo re than 20,000 Web authors to cooperate. On the Internet, wireless Internet has a wealth of content operations experience, reading the users structure, needs, content management and control have a deep understanding. Operating experience and extensive collaboration with government departments: Currently, the Chinese already have Monternet online, mobile own business experience of cooperation, the Chinese telecom operators have a wealth of management experience working system.
Read More..
Brand and customer base better. Earlier from the Chinese network is one of the manufacturers to enter online, through continuous development, has formed a good brand and user base. As of the end of March 2009, page views from the Chinese network has reached 300 million times / day. In addition, from the Chinese networks literature as a grand site, as Shanda comprehensive line of wireless entertainment business, one in human resources, product integration operations (such as the original literature into online games, etc.) also has a large advantage . Chinese online (www.ChineseAll.com) was established in 2000 at Tsinghua University, is one of Chinas Internet publishing pioneer, leading to the most legitimate digital content broadcaster. At present, the Chinese online products or services related to educational institutions, government agencies, public consumption, in various market development in a leading position.
Chinese online product content, copyright and other aspects of operations and customer base are more advantages, mainly in the following points: rich, extensive resources: Chinese online digital rights in China earlier one operating company, has accumulated a rich content resources, in addition to the Internet with the original literature, but also a broad range of primary and secondary education for users, courseware and other content resources, and have literature classes, art classes, childrens class, economics and management, integrated classes, education classes, lifestyle, tools and other literary works. This type of cell phone jammer can work as long as the antenna is collectively connected and the power supply is switched on.
Resources are more extensive content partners: Chinese online now with publishers, writers, original site, the book established the upper range of content partnerships, at present, with more than 400 publishers, more than 8,000 well-known writer, mo re than 20,000 Web authors to cooperate. On the Internet, wireless Internet has a wealth of content operations experience, reading the users structure, needs, content management and control have a deep understanding. Operating experience and extensive collaboration with government departments: Currently, the Chinese already have Monternet online, mobile own business experience of cooperation, the Chinese telecom operators have a wealth of management experience working system.
Wednesday, December 18, 2013
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.
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!
Sunday, September 22, 2013
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. 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!
Read More..
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. 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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