How To Set Up Your LG Ericsson Phone

Telephone LG GS-5140. Radioradar

Home Electronics Repair Telephony

The electrical circuit of the telephone is based on the use of three microcircuits:

Tone calling device GL6840B;

Electronic dialer UM91214A;

Conversational tract GL6965.

The designation and numbering of the elements in the circuit diagram (Fig. 1) correspond to the marking of the printed circuit board (Fig. 2) of the apparatus.

In the call mode, the PBX signal is sent to an AR arrester connected in parallel to the line, which protects the telephone input from overvoltage. Further, through the chokes L1, L2 along the circuit R1, C1, the signal passes to the IC68 tone calling device IC type GL6840B. From the output of the microcircuit, the call signal is fed through the volume level switch SW1 to the piezoelectric transducer BZ1.

Capacitor C2 and resistor R2 are designed to correct the frequency of the master oscillator of the GL6840B chip.

In the automatic telephone exchange response mode, the signal through the chokes L1, L2 passes to the diode bridge VD1-VD4, switch SW4, transistor Q1 and arrives at the talk node made on the IC3 chip (GL6965).

The electronic dialer is made on the IC2 UM91214A chip. The dialing method is set by switch SW2: in position P. Pulse, T. Tone.

When lifting the tube to the pin. 9 IC IC2 appears high level, opening the pulse switch on transistors Q1 and Q2. With pulse dialing on the pin. 9 low level is formed. The key Q1, Q2 is closed, the resistance of the telephone line increases, which is perceived by the PBX as dialing. The power supply of the chip during dialing is provided through the R8 VD5 circuit. With vyv. 8 IC2, a blocking signal is received at the talk node (pin 9 IC3), eliminating switching interference during pulse dialing and blocking the microphone operation during frequency dialing.

The dialer chip is powered in colloquial mode from the VD1-VD4 diode bridge via the circuit: SW4-Q1-R13-VD6, pin. 6 IC2 and is supported by the ZD1 zener diode at 5.1 V.

The cascade on the Q3 transistor type KN2222 (2N2222) implements the function “hang up” when lowering the tube. When the switch SW4 is in the lowest position according to the scheme, the base of the transistor is connected to a common wire through the resistor R11, which ensures the locking of the transistor. When the switch SW4 is in the upper position (the tube is off), the transistor opens through the resistor R10. An open transistor Q3 connects pin. 1 (NK) IC2 to the common circuit wire, providing a “low” level on it, which allows the chip to work in dialing mode.

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The telephone keypad consists of a standard typing field and additional buttons.

Possible malfunctions and methods for their elimination

No ringtone

In this case, first control the supply voltage of the microcircuit pin. 7 IC1. It should be borne in mind that the value of the voltages at the terminals of the ringing device microcircuit is indicated relative to its pin. 2. If there is no power, check the elements R1, C1.

Also check the health of the switch SW1 and the piezo emitter.

If the above steps did not resolve the defect, replace the GL6840B (IC1).

No PBX signal when picking up the handset

Check for the presence of contacts in the TIP / RING connector, the health of the switch SW4 and transistors of the pulse switch Q1, Q2. If everything is normal, the IC2 chip may be malfunctioning. Before replacing it, make sure that there is a supply voltage on the pin. 6. If there is no power, check the elements R13, VD6 and ZD1. There is no dialing, a continuous PBX signal is heard in the handset

Check if the dial mode switch SW2 is set to “P” (pulse). Make sure that the transistors of the pulse switch Q1, Q2 are working. Check the health of the power circuit of the IC2 chip and use the presence of dial pulses on its pin. 9, when pressing the buttons of storage, did not lead to the elimination of the defect, replace the chip GL6840B (IC1).

No PBX signal when picking up the handset

Check for the presence of contacts in the TIP / RING connector, the health of the switch SW4 and transistors of the pulse switch Q1, Q2. If everything is normal, the IC2 chip may be malfunctioning. Before replacing it, make sure that there is a supply voltage on the pin. 6. If there is no power, check the elements R13, VD6 and ZD1. There is no dialing, a continuous PBX signal is heard in the handset

Check if the dial mode switch SW2 is set to “P” (pulse). Make sure that the transistors of the pulse switch Q1, Q2 are working. Check the health of the power circuit of the IC2 chip and use the presence of dial pulses on its pin. 9 when pressing the keys-

Viatura. If there are pulses, then the microcircuit is operational. Otherwise, the chip must be replaced.

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The caller cannot hear you

In this case, the microphone may be defective. It will be replaced with a known-good one. Check the health of the power circuit elements of the microphone power circuit: C15, C18, R31. Control the voltage on the pin. 9 IC3. If it is missing or understated, check the power circuit of the IC3 chip. Also check the resistors R19, R27 for an open.

If everything is normal, replace the IC3 chip.

If it is impossible to dial one or more digits, it is necessary to clean the contact pads of the keyboard circuit board. Also clean contacts from conductive rubber. If this does not help, repair the remote control repair kit.

Phone circuits can be downloaded here.

Date of publication: 01/20/2012

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Wired Telephone Guide LG GS-5140

Found instructions for the LG GS-5140

If the instruction is not complete or additional information is needed on this device, if you need additional files: drivers, an additional user manual (manufacturers often make several different technical assistance documents and manuals for each product), the latest firmware version, then you can ask a question administrators or all users of the site, everyone will try to quickly respond to your request and help as quickly as possible.

Your device has the following characteristics: Answering machine: no, Display: no, Speakerphone: no, Memory (number of rooms): 3, One-touch dialing (number of buttons): no, Volume control: ringer, for full details, see the next tab.

Download the user manual for Landline phones LG GS-5140. Useful files and software

No files found
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Instructions for similar Wired Phones. Lg GS-5140 Reviews

Bogachev Mikhail on the GS-5140 test 2018-02-12 14:17:37

Features LG GS-5140

Device Description Text.

Wiring Phones Failure

Here is a list of the most common and common breakdowns and malfunctions of corded phones. If you have such a breakdown, then you are in luck, this is a typical malfunction for the LG GS-5140 and you can ask a question about how to fix it and you will be answered quickly or read in the questions and answers below.

Breakdown NameBreakdown DescriptionAct
No soundquestion
Headphone crackquestion
No signalquestion
No number dialedquestion
How to connect the cablequestion
stopped working on the networkquestion
the subscriber does not hear youquestion
continuous zoom when dialingquestion
does not hold sound volumequestion
The determinant does not workquestion
no evonka veeovaquestion
Speakerphonequestion
the tube is silentquestion

Add breakage

Damage to the LG GS-5140

If none of the breakdowns from the list above fits the description for your case, then you can add your breakdown and wizards from service centers or just site visitors will be able to advise you. It’s free!

Read more:  How To Find An Asset Phone Number

Services specialized in the repair of corded phones

In our database now 18 353 services are registered in 513 cities of Russia, Belarus, Kazakhstan and Ukraine.

Services selected by users. Services in order

Wired Telephone Instruction LG-Ericsson GS-5140

Found instructions for the LG-Ericsson GS-5140

If the instruction is not complete or additional information is needed on this device, if you need additional files: drivers, an additional user manual (manufacturers often make several different technical assistance documents and manuals for each product), the latest firmware version, then you can ask a question administrators or all users of the site, everyone will try to quickly respond to your request and help as quickly as possible.

Your device has the following characteristics: Answering machine: no, Display: no, Speakerphone: no, Memory (number of numbers): no, One-touch dialing (number of buttons): no, Microphone mute button: yes, see the next tab for full specifications.

Download the manual for Corded Phones LG-Ericsson GS-5140. Useful files and software

No files found
to add a file

Instructions for similar Wired Phones. Lg-Ericsson GS-5140 Reviews. Features LG-Ericsson GS-5140

Device Description Text.

General characteristics
Answering machinenot
Displaynot
Speakerphonenot
Memory
Memory (number of rooms)not
One-button dial (number of buttons)not
Other functions and features
Microphone mute buttonthere is
Volume controlcall
Wall mount optionthere is
Dial Functions
Call forwardingnot
Redialthere is
Tone dialingthere is
Possibility of inclusion in the pause numberthere is

Wiring Phones Failure

Here is a list of the most common and common breakdowns and malfunctions of corded phones. If you have such a breakdown, then you are lucky, this is a typical malfunction for the LG-Ericsson GS-5140 and you can ask a question about how to fix it and you will be answered quickly or read in the questions and answers below.

Breakdown NameBreakdown DescriptionAct
No soundquestion
Headphone crackquestion
No signalquestion
No number dialedquestion
How to connect the cablequestion
stopped working on the networkquestion
the subscriber does not hear youquestion
continuous zoom when dialingquestion
does not hold sound volumequestion
The determinant does not workquestion
no evonka veeovaquestion
Speakerphonequestion
the tube is silentquestion

Add breakage

Damage to the LG-Ericsson GS-5140

If none of the breakdowns from the list above fits the description for your case, then you can add your breakdown and wizards from service centers or just site visitors will be able to advise you. It’s free!

Services specialized in the repair of corded phones

In our database now 18 353 services are registered in 513 cities of Russia, Belarus, Kazakhstan and Ukraine.

How To Set Up Your LG Ericsson Phone