Telephone-Related Circuit

Bird S1000 cellphone repairing diagram 2

Published:2011/11/4 3:15:00 Author:Ecco | Keyword: Bird , cellphone repairing diagram

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Small phone deconcentrator circuit

Published:2011/10/23 22:22:00 Author:May | Keyword: Small phone, deconcentrator

Working principleIfthe line connects totwo phones, which are separately connectedto L and L'. ( We know that when the phone is wating, the different of switch on office line L will have 60V or 48V DC voltage. When it is ringing, there is 95V or 75V AC voltage. When the phone is off-hook, the line voltage will drop to about 10V because the intervene of pnone internal resistance, this device is designed according to this principle. ) If there is phone now, AC current will ring through above-mentioned circuit diagram. If you want to turn to standy phone, the off-hook can dial number keylike standby phone ( attention: thephone must be in impulse dial state). Components choose BG1, B2are MCR100-6 small single-track SCRs, andthey require breakdown reverse voltage to begreater than 100V. D1, D2are 18V voltage regulator diodes. The whole cricuit can load in phone junction box.   (View)

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Hands-free phone chip circuit diagram

Published:2011/10/21 1:56:00 Author:Rebekka | Keyword: Hands-free phone chip

Hands-free phone chip circuit is shown as above, MC3418 chip is widely used in high-quality speakerphone representative blocks and half-duplex voice call.   (View)

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Two-way telephone password device circuit diagram

Published:2011/10/21 2:05:00 Author:Rebekka | Keyword: Two-way telephone password device

Two-way telephone password device is shown as above, the two-way telephone device is composed of the power circuit, password circuit, * circuit, and self-locking circuit. Password circuit is composed of digital keys 0 to 9, four password set. The figure is set to 4269. The *circuit is composed offour one-way thyristor SCR1 ~ SCR4, three capacitors C2, C3, C4, resistor R4, R5 and diode D3. Self-locking circuit is composed of infrared light emitting diodes D5, D6, infrared receiver, the resistance of transistor BG R7, R8 and diode D4. The 2 ends of LINa, LINb Access an outside line. TELa, TELb pick connect the phone.   (View)

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Italy high integrated telephone circuit diagram

Published:2011/9/15 22:48:00 Author:Rebekka | Keyword: Italy, high integrated telephone

Italy high integrated telephone circuit diagram.   (View)

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Anti-toll-fraud sound and light annunciator circuit diagram

Published:2011/9/13 6:48:00 Author:Vicky | Keyword: anti-toll-fraud, sound and light annunciator circuit

Anti-toll-fraud sound and light annunciator circuit diagram is shown in the above picture. The picture is an anti-toll-fraud sound and light warning circuit. It is assembled in the junction box of service entrance conductor. It normally does not consume power or affect the normal work of telephone. When anyone uses the line to make calls stealthily, the luminous diode shrinks, and the annunciator sound sends out warning. Because the voltage of the exterior line of the telephone is higher, the diode VD1~VD4 adopts 1N4004 type diode. Triode V1 and V2 use small-power high reverse voltage tube, such as types （PNP type， note that the polarity of the power supply should be changed） of 2N5551 (it’s reverse voltage is 160V) or 2N5401. The relay K adopts 4098 of small size, and the work voltage uses 3V.   (View)

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Anti-toll-fraud circuit diagram

Published:2011/9/7 5:02:00 Author:Vicky | Keyword: Anti-toll-fraud circuit

Anti-toll-fraud circuit is shown in the above picture. The circuit in the picture is a anti-toll-fraud circuit which also performs collinear security feature. It is mainly made up of illegal parallel examine circuit, noise interference circuit, linear privacy-keeping circuit. The circuit is assembled between the telephone device and the exterior line. When there is toll-fraud, the circuit starts working and sends strong noise to the line, which makes the pulse or double audio frequency sent by the toll-fraud unable to be received. Meanwhile, the anti-toll-fraud indication light is lighted, and the host can track the caller.   (View)

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Wireless telephone adaptor circuit diagram

Published:2011/9/9 7:42:00 Author:Vicky | Keyword: wireless, telephone adaptor

Wireless telephone adaptor circuit is shown in the above picture. The composition of the wireless telephone adaptor is very simple and the cost is very low, while the function is complete and practical. Its functions are listed below: after adding the adaptor, the average wireless can dial two external lines of different region arbitrarily in accordance with one’s demands, which equals two wireless telephone actually. As the user with many extensions, it can also realize making calls among the extensions, and the function of tallback.   (View)

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Simplified Long-Distance Call Lock Circuit Diagram

Published:2011/9/7 0:43:00 Author:Vicky | Keyword: Simplified Long-Distance Call Lock Circuit

Simplified long-distance call lock is shown in the above picture. The lock can lock out the long-distance call without affecting the original function. It ispower-consuming, but it has very good compatibility. If switch K is placed as the picture shows, first dial the number “0”,, and you’ll find the “0” can not be dialed and the long-distance call can not be made while it does not affect dialing “0” when making local calls; if K is placed to the left, then the lock does not function.   (View)

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Simplified Anti Toll Fraud Circuit Diagram

Published:2011/9/7 0:43:00 Author:Vicky | Keyword: Simplified Anti Toll Fraud Circuit

Simplified anti toll fraud circuit is shown in the above picture. The picture is a simplified anti toll fraud circuit. When the telephone is made normally, the indication light is luminous. When anyone wiretaps and makes calls, the circuit will give out fierce alarming sound which prevents the telephone from regular usage. The input lines of the circuit can be divided into positive and negative. The output lines can be connected with the telephone arbitrarily.   (View)

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Bipolar Telephone Circuit Diagram

Published:2011/9/7 0:46:00 Author:Vicky | Keyword: Bipolar Telephone Circuit

Bipolar Telephone circuit is shown in the above picture. The circuit is a typical applied circuit of bipolar telephone IC SC34014. The circuit is simple, and the lowest work voltage is 1.5V when the call isunder usage. 34014 has a stabilized output voltage of 1.2V (providing working voltage for electret microphone); it has a stabilized DC voltage of 3.3V and current output of 550μ, and the current increases to 2mA when dialing.   (View)

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UM95088 Telephone Circuit Diagram

Published:2011/8/9 18:30:00 Author:Vicky | Keyword: Telephone Circuit

UM95088 telephone circuit diagram is shown in the above picture. UM95088 is specialized integrated module of dual tone multiple frequency for telephone dialing. It adopts the techniques of CMOS with dual-in-line package of 14 pins. Dual tone multiple frequency telephone schematic circuit made of the above IC, mainly comprises power supply, key board, dialing and transmitting network, and ad-dc coupling circuit (the ring circuit is omitted in the picture) etc.   (View)

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Circuit diagram of memorial anti-toll-fraud alarm

Published:2011/8/9 20:47:00 Author:Vicky | Keyword: memorial anti-toll-fraud alarm

Memorial anti-toll-fraud alarm Despite the functions of general anti-toll-fraud telephone, the telephone anti-toll-fraud alarm has functions of alarm for toll fraud by doubling the line, and alarm for toll fraud by breaking the line. In addition, it does not need external power supply. The telephone anti-toll-fraud alarm is mainly composed by CMOS integrated circuit. The composition is very simple. It is mainly polarity reversing circuit (Q1 and Q2), voltage detection circuit (R2, VD1 and VD2), logic-judging circuit (A1), memory display circuit (A2 and V1), and alarm-driving circuit (V2 and V3 buzzer) etc.   (View)

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On-Hook Anti Toll Fraud Device Circuit Diagram

Published:2011/8/9 18:26:00 Author:Vicky | Keyword: On-Hook, Anti Toll Fraud

On-Hook Anti-Toll-Fraud Device The circuit controls the on-off of relay by making use of the changes of voltage brought by on-hook and off-hook of the telephone. S is a exterior switch, which is closed usually. Usually the high voltage of the external line can guarantee the regular work of V (the current of collector is 4mA). The relay works, and the closed contact of K is open, which does not affect the usage of the telephone. When there is toll fraud in the external line, the voltage of the line is lower than 8V, K does not work, and the closed contact makes the external telephone T and R under short circuit. Therefore the external telephone T and R cannot work then. The user can open S, and close it after VD3 is lighted. Then the circuit is under anti-toll-fraud situation.   (View)

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Telephone on-hook warning circuit diagram

Published:2011/8/9 18:31:00 Author:Vicky | Keyword: Telephone on-hook warning circuit

Telephone on-hook warning circuit diagram is shown in the above picture. The IC uses CMOS Shmidt hex inverter CD40106. C1 is better to use ceramic capacitance which can withstand voltage of over 100V, and L is better to choose small color-code inductor. There are no special requirements for the rest component. When the telephone is on-hook, there are several tens of volt-ampere in ends T and R. A short period of sound indicating on-hook is given out via HTD. It is shown in the picture (a). Because the sound only uses the memory function of C4, C4 can only be re-charged when the telephone is off-hook next time after the sound is given out. And the warning sound can be given out when the telephone is on-hook next time. The assembling diagram is shown in the picture (b).   (View)

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Simple telephone time lock circuit diagram

Published:2011/8/9 18:33:00 Author:Vicky | Keyword: Simple telephone time lock circuit

Simple telephone time lock circuit is shown in the above picture. In the circuit diagram, BG1 and BG2 are electronic switches controlled by IC NE555. When the telephone is on-hook, the DC resistance value of the telephone is over 600KΩ, the current when the external line runs into the IC is very low, and the electronic time lock does not work. When the telephone is off-hook, the telephone DC resistance value reduces to 500Ω, and the electronic time lock works. After the call has been made for a certain period of time, pin 3 of the IC turns into low potential, which forces BG1 to stop. The exterior pressure drop is mainly on the electronic switch, which results in the telephone’s inability to work. And the call is suspended.   (View)

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Telephone Automatic Answering Device Circuit Diagram

Published:2011/8/9 18:34:00 Author:Vicky | Keyword: Telephone, Automatic Answering Device

Telephone automatic answering device circuit is shown in the above picture. The recording telephone device has strong ability of anti-disturbance, which avoids some unexpected matters. When the telephone rings for 6 times without answering, the device will imitate automatic off-hook. Then the telephone is on and gives out the following words: “hello, the host is not in home. Please leave a short message.” Meanwhile, the recorder is connected, and records the detailed content of the speaker’s words.   (View)

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Telephone Automatic Recording Control Device Circuit Diagram

Published:2011/8/9 18:35:00 Author:Vicky | Keyword: Telephone, Automatic Recording Control Device

The telephone automatic recording control device circuit is shown in the above picture. When there is ringing signal in the line (90V, 15Hz) or the telephone is off-hook, the delayed pin 3 of NE555 shows high potential, which makes J conducted. The AC power supply of the recorder is conducted by the contact and automatically records the message. It stops recording when the telephone is off-hook or the power supply is cut. K is the manual-operational switch, and is used to control the power supply during sound reproduction.   (View)

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Real-time Telephone Automatic Recording Device Circuit Diagram

Published:2011/8/9 18:38:00 Author:Vicky | Keyword: Real-time Telephone Automatic Recording Device

Real-time telephone automatic recording device circuit is shown in the above picture. Despite automatic recording for the making calls and answering calls, the recording device can also automatically input the time of recording before recording the message , which makes the recording material more detailed and accurate and thus easy to be picked out and analysis. IC1 and IC2 in the picture are time-base integrated circuit NE555. The voice timing system uses UT-6657 type made-up timing table. Relay J1 and J2 are HG4098. The coupling device is 4N15, and the diodes are IN4007.   (View)

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Microcomputer Telephone Cost-Saving Device Circuit Diagram

Published:2011/8/9 18:40:00 Author:Vicky | Keyword: Microcomputer Telephone Cost-Saving Device

The microcomputer telephone cost-saving device circuit is shown in the above picture. The circuit is made of anti-wiretapping and central processing. PIC16C56 is the central part of the whole circuit. Anti-wiretapping part is composed by VD5-VD8, A4, V4, V5 and HA. The operation of the device is very simple. It has no limitation on the business phones and the phones can be dialed directly; when making business calls, dial the general code first and then dial the telephone number. Then hang up the phone for 4S. The device automatically goes back to the state of limiting the non-business telephone.   (View)

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