In detail: do-it-yourself repair of a Panasonic wireless phone from a real master for the site my.housecope.com.
The digital cordless telephone handset may require repair. Complaints: when dialing a number, you have to apply more force than usual when pressing the keys. If you do not pay attention to this inconvenience and continue to train your fingers and the stability of your nervous system, then over time, some keys will generally stop responding to pressing with any force. And then we make a conclusion - the telephone receiver is broken. You need to carry it to repair or buy a new one. Such a "diagnosis" for a telephone handset does not always require paying for the work of a foreman in a workshop or buying a new handset. Here's how I dealt with this problem myself at home, in only about thirty minutes. Such actions are within the power of any person who knows how to hold a screwdriver in their hands.
Panasonic digital cordless telephone answering machine. Manufacturer: Kyushu Matsushita Electric. But the handset can be of any manufacturer. All such handsets have a similar device. And the cause of the malfunction in this case may be the same for everyone - there is no contact between the rubber contacts of the keys and the contacts on the phone board.
Unscrew the mounting screws on the back cover case. In this model, they are located under the compartment cover that covers the finger-type batteries.
Remove the compartment cover, take out the batteries. (see photo)
Unscrew the fastening screws with a screwdriver.
Next, we slightly open the lower part of the case from the side of the batteries.
And in the upper part of the case, we pull it back a little with a screwdriver in order to remove the plastic part of the case from the latch.
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Video (click to play). |
When removing the half of the plastic case, such a detail may fall out. (see photo)
We can easily put it back in place. (look at the photo)
Then we unscrew the screws securing the board.
And in these places (look at the photo, the screwdriver indicates) the board fastening latches. Pry slightly with a screwdriver and remove the board.
So we got to the contacts that just need to be cleaned, which is what we are doing.
We assemble the tube in reverse order. And the dial buttons work like new again! And I will also give this advice on using batteries. Replace the handset on the charging base only when the low signal sounds. This will extend the life of the batteries.
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Malfunction manifestation: weak light of the indicator, a message about a bad battery, although it is fully charged. Defect in diode D1 according to the scheme. How to find: check the presence of 5.5 volts at the anode, the voltage at the cathode should be 5.2 volts. If the cathode voltage is below 4 volts, then the diode must be replaced.
2). "PANASONIC" models 3611, 3621.
The following defect is observed: There is no connection between the tube and the base - the reason for this is the poorly soldered lead of the transmitter quartz in the tube.
3). In the answering machine “PANASONIC” model 4311.
During normal operation of the tube and base, there are malfunctions in the operation of the AO - the cause is increased pulsations of the power supply unit.
4). Panasonic 9080 and the like.
During operation, a crackling sound is heard that disappears (for a while) after being hit or disassembled. Reason: poor contact in the connector between the RF unit and the board.
Repair: 1). each pin of the connector is carefully rotated 90 degrees.
2). we solder the connector and solder in place of its pieces of tinned wire
To change the TONE PULSE mode, press the following key combination.
1 PROGRAM
2 AUTO
3 to select PULSE mode press # 2 times
to select TONE mode, press * 2 times
4 PROGRAM
The handset does not work, while there is a keyboard interrogation - the Zener diode D17 flew out on the mx power supply;
КХ-ТС900 and similar ones: the radius of action has become small - the filter "leaks" at 903 MHz in the tube;
KX-T9500: unstable connection tube-base, and the base-tube is excellent - the noise detector in the tube is playing pranks. Treatment - filter replacement at 455KHz; / p>
KX-T7980, 9050, 9080, 9280: there is no tube-base connection due to the drift of the transmitter or receiver frequencies (a frequent defect in 3-4 year old devices) - the trimmer capacitors in the HF unit have oxidized;
KX-TC408 and the like: it is impossible to adjust the frequency of the transmitter - you need to replace the varicap.
You can check the operation of the base and tube transmitters as follows: we make an equivalent load: We remove a 1.5v backlight lamp from an unnecessary wristwatch, solder a small piece of 50 Ohm coaxial cable to it and connect it to the RF output of the unit instead of the antenna. With a working transmitter, the light should glow brightly at 30mW.
eight). Defect in Panasonic KX-T9050, KX-T9080.
There is no or unstable connection between the base and the handset. I recommend setting up RF blocks, this is done as follows:
Handset: We solder the jumper to enter the test mode, press the Pause button (noise is heard in the speaker). By rotating the TX and RX trimming capacitors, set the voltage to 1.8v at the VXO control points for TX and RX, respectively. For this operation, it is desirable to have a repair cable, but you can do without it by soldering to the control points with a short piece of wire (the control points are on the bottom side of the RF block). It is convenient to monitor the voltage with an oscilloscope 0.5v / div. The setting is quite “sharp”; it is necessary to rotate the trimmers with a dielectric screwdriver. I use screwdrivers made from a strip of fiberglass with foil removed and sharpened accordingly. It is also helpful to tune the 12.800 MHz reference oscillator. We connect the base to tel. lines, we establish communication, with an oscilloscope we look at the signal at the output of the tube discriminator - 400Hz. - line tone. By rotating the trimmer, we achieve the maximum undistorted signal amplitude. By adjusting the discriminator contour, we achieve the same. Base: Configurable in the same way. To enter the test mode, three contractors are short-circuited. point, then power is supplied. Tighten all the screws in the RF units well before adjusting.
Fault: very quiet audibility of the subscriber in the receiver. The connection between the handset and the base is established normally and the signal from the microphone of the handset, in intercom mode, is heard on the base normally. Determining, in this case, where the malfunction is in the handset and base is very simple. Suppose you have a handset and a base connected to each other (in the same intercom mode), at this moment it is necessary to de-energize the base (remove the base power supply from the socket) and if you hear a loud noise in the handset, then the malfunction must be looked for in the base. In addition, indirectly, loud clicks from its speaker when you dial a number indicate that the handset is working properly. My malfunction was caused by poor metallization of the via in the base, between components R27, C11 (15th pin of IC4). By lightly pressing on the board with a screwdriver, it was possible to localize the malfunction.
Fault: there is no connection between the handset and the base. As I was told, instead of 4.5V, they connected 12V to the tube. But the tube turns on and looks for the base. As a result, only the transistor assemblies Q14 and Q15, as well as the diode D13, turned out to be faulty (i.e., no power was supplied to the RF unit).
eleven). All Panasonic KX-T7980 radiotelephones. 9080.
Fault: during a conversation and at the same time when you move, unpleasant rustles are heard in the receiver. The antenna turned out to be faulty (it was necessary to pick less in the ear). The antenna “spring” is inserted into the brass adapter; on the other side, a plate with a hole is inserted into the adapter. It is necessary to move the antenna and if you hear rustles in the tube, then you just need to squeeze this adapter, but not much, otherwise it may burst. If it does burst (or compression does not help), then it just needs to be properly soldered.
thirteen). Panasonic KX-T9000, KX-T9080.
The tube does not work or is making a fool, there is no connection with the base.Check the power supply to the circuit after the three-pin IC6 microcircuit, if less than normal, change it.
14). All models of Panasonic cordless telephones type 408.
The handset loses connection with the base due to the following reasons:
1. Large ripple of BP. and because of this, the handset does not exchange the PIN code with the base. The malfunction is eliminated by replacing the 470 Mkf capacitor with 1000 Mkf and more in B.P.
2. Failure of the Zener diode in the tube charging circuit, the batteries are charged to overvoltage and the tube with the base does not exchange a security code (PIN code).
3. Do not exchange PIN-code due to dirty contacts on the charger base or due to mechanical damage to these contacts.
4. The filters in the radio channels of the base and the tube are upset. Many tuning methods have been described if normal frequency analyzers are not available. I suggest another one, for those models that have a Speaker button on the base. If you put the handset on the base, press this button on the base, and then pick up the handset, the algorithm for connecting the handset to the base will be performed. But when the radio channels are out of tune, the passage of speech signals is not audible. It remains in this position to adjust the filters and achieve the passage of both voice and telephone signals.
The connection between the tube and the base is lost. A defect in the contact group of the charge at the base, - (the contacts are connected to the tube through a spring-loaded switch ?!). During operation, the connection fails and of course the PIN code. It's hard to understand right away!
The radius of action of 1.5-2 meters has greatly decreased. A faint noise is heard in the handset when establishing a connection, even at a short distance. Calculated that there is a malfunction in the tube (in the radio receiving path). Usually, the RF amplifier is to blame for the decrease in sensitivity (knocks out a field-effect transistor (in Panas most often) or a bipolar one (this is exactly what is here). Replacing the transistor did not give any result. Next, only m / s TB31224F- 1st mixer, 1st heterodyne , 2nd mixer, etc. before the demodulated signal Since it is problematic to replace it, I tried to replace the filter at 455 kHz.
During the repair process, I encountered a tube malfunction, the processor does not start and does not respond to button presses. It turned out that the diode D15 was flashing from the battery to the charging mark. As a result, Q15 opens and the tube thinks that it is on the base. The dialing tester does not leak. Thus, I restored 3 devices.
The range drops, then first of all it is necessary to check the bandpass filter in the tube (item designation FL405). It is almost 100% dead.
nineteen). Panasonic KX-T9050B, KX-T9080BX, KX-T9000, KX-T9100, KX-T9200, KX-T9150, KX-T9250.
Sign: Noise during conversation. Cause: When the battery is discharged, the voltage changes, which causes noise in the tube. Elimination. Change the resistance value R87 6.8kOm to 12kOm.
Panasonic technical support service.
twenty). After the breakdown of the shutdown mechanism (handsets of the Panasonic 7980 telephone and the like).
Structurally aligned with the axis of the hinged cover, after analyzing the circuit diagram of the tube, I used a conventional reed switch with normally open contacts to control the tube. I placed the reed switch in the area of the tube LEDs under the board, fixing it to the light guide so that its axis was along the tube. In this position, the reed switch is most sensitive to the magnet, which is located at the end of the hinged cover. I used a magnet rectangular from a magnetic furniture latch, it did not need to be reworked. The standard switch is shorted with a drop of solder. One end of the reed switch is connected to the common wire (-), the second to the 60th leg of the processor (it is better to solder to R105, which can be found on the left edge of the board: one of the contacts of the standard switch is connected to two resistors, one (R49) to the common wire, another (required R105) to D18 and 60th leg of the processor). When the tube cover is closed, the reed switch provides a low level at the 60th leg of the processor corresponding to the CLOSE mode.
21). PANASONIC KX-T408 radiotelephone and similar.
In several devices of this type, a defect was found, the external manifestation of which was as follows: with a working battery, the handset did not react in any way to pressing the keyboard buttons. When checking with an oscilloscope, it was found that the 32.768 kHz clock generator was working, and high voltage levels were present at the inputs 5-7 of the microcontroller instead of low ones. The reason is a break in the printed conductor connecting pin 3 of IC3 with pin 33 of the microcontroller. We measure the voltages at these terminals, which should be the same and have a level of about 3.5V. If the voltage level is low at pin 33 of the microcontroller, we connect the indicated terminals with a jumper from the MGTF wire.
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On a cursory examination, the symptoms of both fire victims turned out to be similar, a complete refusal to start - there was no characteristic "pip" when power was applied and the inductance at the telephone line input was broken.
The problem is seemingly insoluble. But after the diagnostics (let me remind you that before that the radiotelephones were being repaired in a couple of workshops), it turned out that the 1117S power stabilizer, which powers the 3.3V processor, is to blame.
After running a couple of stores and hearing that this microcircuit is not even in the price lists and it will take a long time to wait for a new one, I bought the good old LM317. I assembled a simple stabilizer and turned it on instead of the above microcircuit.
The phone responded with a joyous "rush".
I replaced the input inductors and checked the transistors of the set - everything is fine, the radiotelephones are working.
And it became one more successfully animated device more :) Best regards, UR5RNP.
SIEMENS cordless telephone The Gigaset 1010 handset is on a PIN code, the code is naturally unknown. we solder the EEprom 24c04, read it with Poni Programmer and look at the addresses: 27 and 28 there is the coveted PIN in an explicit form.
Panasonic KX-T9080, 9050 You can check the operation of the base and tube transmitters as follows: we make an equivalent load: We remove a 1.5v backlight lamp from an unnecessary wristwatch, solder a small piece of 50 Ohm coaxial cable to it and connect it to the RF output of the unit instead of the antenna. With a working transmitter, the light should glow brightly at 30mW.
Cordless telephone PANASONIC KX-T408 and similar.
In several devices of this type, a defect was found, the external manifestation of which was as follows: with a working battery, the handset did not react in any way to pressing the keyboard buttons. When checking with an oscilloscope, it was found that the 32.768 kHz clock generator was working, and high voltage levels were present at the inputs 5-7 of the microcontroller instead of low ones. The reason is a break in the printed conductor connecting pin 3 of IC3 with pin 33 of the microcontroller. We measure the voltages at these terminals, which should be the same and have a level of about 3.5V. If the voltage level is low at pin 33 of the microcontroller, we connect the indicated terminals with a jumper from the MGTF wire.
As a result of increased voltage in the mains, varistors often fail. They are used for surge protection.
Apparatus Samsung CK-5341ZR.Some time after switching on (from 15 minutes to several hours), tuning starts to go away, or when switching from channel to channel, it sometimes does not capture the station. I tweaked the APCG circuit (he is the only one in the TDA8362 harness) - it did not help. I replaced the zener diode at 31 Volts (in the tuning circuit) - it did not help. I changed the TDA8362 itself - no result. Changed the memory (24C02) - it didn’t help. I wanted to change the control processor (SIM-135-2R С69540Y), but it’s too expensive. The owners were in a hurry, and the iterations were lengthy, so I filtered the low-voltage supply voltages and tuning voltage with semiconductor capacitors and changed the tuner itself. The device has not been malfunctioning for two months now. Unfortunately, I cannot specify the exact reason - either the tuner itself, or knocked down the power supply ripple setting.The fact is that before that I was repairing a Soviet TV with a built-in 55-channel remote control, and its settings were also lost, so the reason turned out to be that the electrolytic capacitor 470 μF / 25 V at 12 Volts in the MP- 3-3. The SAA1293 processor in the remote control was powered from the same voltage. The image was not affected by the loss of capacity.
Panasonic KX-T9000, KX-T9080: The handset does not work or is making a fool, there is no connection with the base. Check the power supply to the circuit after the three-pin IC6 microcircuit, if less than normal, change it.
PANASONIC KX-TCD951: you cannot register a pipe - solder a USB flash drive in the database
LG GT-7101, SEIMENS GIGASET: segments on the indicator disappear - solder the indicator cable through thick paper (Whatman paper)
PANASONIC KX-TC1019: no connection tube-base - register the tube. The 5-digit code is indicated on the paper label (in the base, short-circuit R909 next to the process and apply power, press 2.7, # on the pipe and apply power, dial the code. If everything is OK, the pipe goes into conversation mode)
PANASONIC-and with a lever on the base at the charging contacts: no charging or matching - solder the contacts by removing the springs
LG GT-7320: it is impossible to exit the Direct Call mode - there is an inaccuracy in the instructions in Russian - exit by double pressing (in 0.5 seconds) the microphone mute button
SIEMENS GIGASET, BT: no line - 2 and 5 pins are often used in the telephone jack (DOMESTIC CABLES USE 3 AND 4)
LG CT-9130 and GT-7101 use different polarity on contacts in power supplies
PRIMER, SANYO CLT, CLA: in case of failure of the reed switch, you can replace the reed switch itself with a domestic small-sized
LG GT-9130A: noises in the pipe - replacing the 3.99 MHz quartz in the pipe with quartz in a metal case can help
PANASONIC-and new models (not DECT) when the pipe enters the water under the process, a conductive blot is formed in 98% of cases
All models of Panasonic cordless phones type 408, the connection between the handset and the base is lost due to the following reasons:
1. Large ripple of BP. and because of this, the handset does not exchange the PIN code with the base. The malfunction is eliminated by replacing the 470 Mkf capacitor with 1000 Mkf and more in B.P.
2. Failure of the Zener diode in the tube charging circuit, the batteries are charged to overvoltage and the tube with the base does not exchange a security code (PIN code).
3. Do not exchange PIN-code due to dirty contacts on the charger base or due to mechanical damage to these contacts.
4. The filters in the radio channels of the base and the tube are upset. Many tuning methods have been described if normal frequency analyzers are not available. I suggest another one, for those models that have a Speaker button on the base. If you put the handset on the base, press this button on the base, and then pick up the handset, the algorithm for connecting the handset to the base will be performed. But when the radio channels are out of tune, the passage of speech signals is not audible. It remains in this position to adjust the filters and achieve the passage of both voice and telephone signals.
If the company radiotelephones Panasonic KX-T9080 or similar ones (hinged lid) there were problems: the stem broke or the lid broke, then it can be modified with the help of a simple device assembled on a K561LN2 microcircuit. This is the most original and simple solution to the problem that I have come across. The device is easy to assemble, it works very well, it never fails. The lid and stem can be bought, the price of the complete lid (lid, cable, microphone, bell) costs about 1000 rubles, the salumin stem will cost 300 rubles. Very often you meet clients who refuse to replace expensive components. And you are losing money and a customer.
In these phones, the call can replace the actual earpiece. With the help of a fluoroplastic wire, it is necessary to connect the negative terminal of the capacitor C40 (it is the decoupling between the generator of the bell circuit and the emitter itself located in the phone cover) with the contact P of the headphone, in Figure 1 there is a red dot.
2. Scheme replacing the S2 button (this button turns on the handset when the cover is opened)
The diagram in Figure 2 is assembled on the K561LN2 microcircuit. Moreover, only the 14th part of the microcircuit is used. Electrolytic capacitor C1 47 MKF from 6, 3 to 16 volts. used in the circuit should be small, for ease of placement in the tube body. Resistors of the SMD type are mounted directly on the microcircuit. The S3 button is a button to temporarily mute the microphone.The tracks from the button to the circuitry of the phone need to be cut. The places where the tracks are cut are shown in Figure 3 with red crosses.
Leg 7 of the microcircuit must be connected to the body of the telephone circuit in any convenient place. Leg 14 of the microcircuit must be connected to a switch that turns off the telephone receiver Figure 5, the connection point is shown with a red dot.
The old microphone can be used, which must be removed from the socket in the cover. You can fix it in the hole that remains in the tube body from the stem. Observe the polarity when wiring the microphone. The negative side of the microphone is connected to its body. Figure 6 shows the microphone connection points.
Figure 6 shows the connection point for tap S2, see diagram.
You need to place the switch circuit under the phone board in the area of the headphone. The scheme does not require any additional settings.
3. How the modified tube works. When you receive a call on the handset or, if necessary, make a call, you must press with your thumb on the button that previously performed the function of mute the microphone. After the end of the conversation, the button must be pressed again. The handset will go into standby mode.
This refinement has been tested on several models of Panasonic phones. For two months, not a single complaint has been received from the owners of the converted devices.
We are still waiting for similar letters from you, with personal experience in the repair of household appliances
Dimon
Restoration of the lock of the battery compartment cover of the portable tubes
When operating and repairing portable handsets for cordless telephones (BCT) from PANASONIC and other manufacturers using a similar case design, it is often necessary to restore the battery compartment cover lock. The latch-latch of the lock is made of plastic in the form of a protrusion on the lid and, if handled or dropped, the tube often breaks off. This problem causes a lot of trouble for users and repairmen, since various restoration options using glue, plastic inserts, etc., as practice shows, are short-lived. As a result, the lid has to be fixed with tape.
Provides a more reliable, simpler, and proven recovery method that is less time consuming. The additional parts installed in this case, as well as the places of their attachment to the lid, are shown in Fig. 1a and 1b. The main part is a metal spring plate 1, which will serve as a latch. It must be made independently in accordance with Fig. 2 for handsets "Panasonic KX-TC418", etc., or changing the dimensions for a specific model. The plate can be made of beryllium bronze by heat treatment of the workpiece, or from any suitable metal, for example, spring contacts from a relay, etc.
Rice. 1. Installation of additional parts, as well as the place of their attachment to the cover
Drill (or punch) two holes with a diameter of about 1 mm in the workpiece, and then bend the latch tongue. The plate is attached to the inside of the lid using a conventional office clip 2 (Fig. 1). Previously, two holes 3 with a diameter of about 1 mm are drilled in the lid in place, between which, using a cutting tool (for example, a sharpened end of a file, or a piece of a hacksaw blade, etc.), a shallow groove is cut so that the staple does not protrude from it. Hole 4 with a diameter of 1.5-2 mm is drilled at the edge of the lid so that through it you can press the plate from above with any metal rod (for example, an awl, nail, etc.), squeeze the latch and open the lid.
Inspection and restoration of antennas of portable cordless telephones manufactured by PANASONIC
In many PANASONIC BSHT models, operating in the 30-50 MHz frequency range, a spiral antenna is installed, the design and appearance of which with the cover removed are shown in Fig. 3. During operation, excessive bending and deformation of the antenna is often neglected. As a result, the wire of the internal extension coil is broken.The normal operation of the phone is disrupted, noise appears, the range decreases, the quality and reliability of communication between the handset and the base decreases. Not knowing this reason, some radio mechanics begin to look for a malfunction in the radio channel blocks of the handset or base. Since the antenna of the tube is flexible, it gradually returns to its normal position and externally signs of deformation become invisible. Therefore, before proceeding with the repair of the electronic part of the BSHT, it is necessary to check the serviceability of the antenna.
Rice. 3 (a, b). Antenna device and the appearance of which with the cover removed
Indirect evidence of a malfunction is a decrease in field strength, especially around the top of the antenna. This can be determined using a field indicator or a high-frequency voltmeter (if its remote HF head with a specially extended probe-antenna about 50 mm long is brought to the upper end of the antenna 5). To carry out such a check, it is necessary to have some experience in repairing the BSHT of these models in order to compare the relative readings of the devices with a working and faulty antenna, as well as the value of the RF voltage directly at the output of the transmitter.
A similar homemade spiral antenna, fig. 4, can be used instead of a broken telescopic one (for example, in the KX-TC1025 model and others). As practice has shown, it is inconvenient to use a tube with a telescopic antenna, since the latter quickly breaks down. For replacement, a spiral is inserted into the plastic case on the tube (Fig. 4b), soldering its lower end to the metal base 4, which remains from the broken telescopic antenna.
Rice. 4. Homemade spiral antenna
A metal plug 5 is soldered to the upper end of the spiral, which is inserted from above into the hole of the cover b. For this, a short bronze or brass screw with an M4 or M5 thread, preferably with a massive head, is suitable. The range of the BShT with such an antenna may decrease slightly, but it becomes much more convenient to use the tube. If the antenna is in order, the malfunction should be looked for in the radio channel blocks of the handset or base.
Malfunctions of BShT associated with design and manufacturing defects of blocks and components
PANASONIC cordless phones can be conditionally divided into several generations by series, each of which is a modified version of the previous series. That is, despite the different functionality of the models, provided by control units, indication and various additional digital storage devices, we can talk about their serial versatility, according to the operating range of 40 or 900 MHz. This provides high potential reliability and durability, not only due to good performance, but also due to high maintainability. In practice, this potential can be realized only under the condition of careful operation, timely qualified maintenance and repair.
For example, if the user allowed moisture to enter the tube on the board and did not disconnect the battery (and did not go to the workshop in time), the repair may become impossible or economically impractical. The same can happen if an additional malfunction occurs due to inaccuracy and errors when trying to unqualified repairs, for example, when checking the modes on the outputs of microcircuits (especially the microprocessor) and their accidental closure; from exposure to static electricity through tools; when using separate measuring devices with mains supply, not connected to a common ground bus; when using a conventional soldering iron that does not have an isolation transformer.These are just some of the most common violations during operation and repair.
A similar thing often happens with the tubes of the KX-TC155V, KX-TC157V models and those close to them in design. For example, in many PANASONIC tubes, as a result of strong pressure on the lower buttons of the keyboard, the conductor under the contact layer of the FLASH button is often broken. As a result, in addition to this button, keys 1, 2, and 3 also do not work. Sometimes this also happens in other models with different contact pads and jumpers applied in the same layer on the typesetting field of the boards. Attempts to restore contact by stripping this layer and soldering the like. are not successful. As practice has shown, in these cases, the most reliable repair method is to restore the required connection on the reverse side of the board. In this case (for the KX-TC1558 and KX-TC1578V models) pin. 8 of the microprocessor (CPU) must be connected to the anode of the diode D34 or to the conductive pad on the board, as shown in Fig. 5. For this it is better to use a piece of wire PEV-2 with a diameter of 0.12-0.15 mm.
Currently, cordless telephones of the KX-TSYUXX, KX-TS14XX, KX-TS15XX models are widely used, the operation and structure of which are described in detail in [1], as well as other, more modern models of this generation, close to them in design and set used electronic components. They use, in particular, small flat dynamic heads, for example, the PQAX3 P23 ZA.
The resistances of the windings of these heads are from 110 to 150 ohms. A significant part of the problems that arise during operation are associated with them. Firstly, the winding of the moving coil of the heads is made with a thin wire, which is often cut off. In this case, it becomes necessary to choose a replacement head, since the original is difficult to acquire. The domestically produced DEMSh-1a capsule is suitable in terms of resistance. To install it in the tube, the capsule must be removed from the plastic housing. Then the capsule leads are carefully soldered off from the clamps and lengthened with PEV-2 wires with a diameter of 0.15 mm. The metal body of the capsule is wrapped around the perimeter with electrical tape or tape. Lay the wires by gluing them with glue from the sides over the electrical tape. Install the capsule in the center of the tube head socket. To prevent it from dangling, the free space between the walls of the socket and the capsule is filled with a strip of foam rubber rolled into a ring, which is also fixed with glue. In this way, several tubes of various models have been restored. The sound quality was rated by users as good.
To better understand the reasons for the frequent failure of branded heads of this type, it was necessary to study their device. It turned out that there is another coil inside the head (Fig. B), located along the edge of the case and wound with a thicker wire.
Rice. 6. Coil inside the head
- Petrov I.A. PANASONIC radiotelephones. Device and repair. M., 2003, MRB, issue 1259.
- Alla / 08.08.2016 - 09:38
Hello! I also have this problem: the phone is charging, but there is no connection, there are no sticks, what could it be? write who knows the answer! thanks! - ANDREW / 05/02/2016 - 21:35
Panasonic KX-TGA820RU when dialing a number there is a long beep prompt the possibility of correction at home 8916 375 6970 - Nadezhda / 01/03/2016 - 20:04
After charging, when you remove the handset from the base, the lamp on the handset is on. - Nadezhda / 01/03/2016 - 20:02
After charging, the light on the tube began to light up. What it is? - Victor / 10/06/2015 - 23:00
Panfsonik KX-TGA110UA radiotelephone - after charging, the indicator on the display shows that the battery is discharged (although when checking it turns out that it is fully charged) and when the phone is turned on, it immediately turns off. Tell me where to look for the reason? There is no scheme. Thanks in advance for your consultation. - angelica / 08/29/2015 - 11:05
Panasonic phone kkh-ts1451v goes a continuous beep when dialing a number, can anyone have instructions pliz, E-mail, - andrey / 07/31/2015 - 16:05
you can hear the call at the base but not on the receiver. - lyudmila / 07/30/2015 - 21:59
I pick up the phone and there is no connection, connect the adapter although everything is connected - Mikhail / 07.07.2015 - 08:36
No ringing call - galya / 04/05/2015 - 18:54
Panasonic KX-TG1611SA began to beep during a conversation, and it was heard to whoever you were talking to. And then it turned off completely now it beeps and turns off so every minute the screen goes out to call it is impossible to call new batteries and did not work for a day - galya / 04/05/2015 - 18:49
Panasonic KX-TG1611SA began to beep during a conversation, and it was heard to whoever you were talking to. And then it turned off completely now it beeps and turns off so every minute the screen goes out to call it is impossible to call new batteries and did not work for a day - Alexander / 03/26/2015 - 07:14
I hear my echo when talking in the receiver. How to fix it? - Evgeniya / 02.24.2015 - 12:27
PANASONIC KX-TC1001. When dialing a number, the continuous beep does not disappear. There is no connection. The call to me is excellent. Please help. Thank you. - Dhaka / 01/29/2015 - 11:10
the sound of the call ringing disappeared, the screen displays a loudspeaker with a double cross at the exit from the bell, I don’t know how to remove it, tell me who can - Tatiana / 08/16/2014 - 11:00
the base does not respond to the handset. and the antenna flashes on the handset, the time and date have been reset and I cannot establish, I try to establish, but in response there are two beeps. What can it be? - Vadim / 07/12/2014 - 18:49
No incoming calls (call) Panasonic KX-TCD540RUM. I ask for help. Thank you - Sergey / 05/10/2014 - 22:27
In general, "Panasonik" radio telephones are as reliable as a tank. (According to the well-known proverb) That with a tank does not always correspond to reality. But the phone has been working for me for more than 11 (or even 12 years - I can’t remember for sure) minor problems of course arose. I thought I’m so neat. But in my absence the neighbor looked after the farm. I didn’t like the color of my 2511, it got dirty from dirty hands in the garden. He plowed regularly on the farm for a couple of years until someone was stolen. the only thing that got in the way was low power. Until the neighbor's house, reliable contact with the base device was not always obtained. As a "techie" I found a way to solve the problem. How I will not say. And the company has good service. - oleg / 11/25/2013 - 11:42
PANASONIC KX-TG720RU They call me normally, but when I try myself, the constant beep does not disappear when dialing, it continues to beep. What kind of breakdown, is it possible to do what, I will be grateful for the answer. mail - tsiganckow.alex / 07.11.2013 - 08:27
I see a lot of questions. Why are there no answers ?? - galina / 10/25/2013 - 07:21
no call ring when dialing a number can not get through to us
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PANASONIC KX-TC408RU-B
Fault: The call works only if the phone is lying on the base or if you press any button during a call.
Remedy: Check the quartz crystals on the pipe processor: for start-up in standby mode and for frequency. Check the level of the charging signal on the processor, do not solder the processor legs and its strapping. Check the crystal resonator on the processor.
VOYAGER CL-1000
Fault: The call does not work when there is an incoming call either on the base or on the handset.
Remedy: Probably, loss of capacity or leakage of electrolyte, which is in the optocoupler circuit, breakage of the capacitor in the input circuit of the optocoupler from the side of the telephone line. You can increase the capacity, reduce the resistor in the same circuit. It is convenient to send a break as a call of the order of 120V through a 1-2 kOm resistor if there is no simulator or friend on another phone. If the phone rings when dialing on a parallel device then all actions are reversed.
PANASONIC KX-F90B
Fault: Does not respond to any button, when turned on, it says that everything is in order and starts the answering machine. Does not receive a signal from the telephone network.
Remedy: Check if one of the buttons is pressed.
PANASONIC KX-TC1025
Fault: The radius of action has decreased.
Remedy: Replace C103 (receiver-IC input filter).
PANASONIC TX-9280
Fault: Weak illumination of the indicator, a message about a bad battery, although it is fully charged.
Remedy: Defect in diode D1 according to the scheme.Check for the presence of 5.5 volts at the anode; the voltage at the cathode should be 5.2 volts. If the cathode voltage is below 4 volts, then the diode must be replaced.
SANYO CLT-55
Problem: Even with a fully charged battery, the BATT indicator flashes. LOW
Remedy: Check processor and trim circuits.
PANASONIC KX-T3611, 3621
Fault: There is no connection between the handset and the base.
Remedy: Check the soldering of the transmitter quartz lead in the tube.
PANASONIC KX-T4311
Fault: During normal operation of the handset and base, there is a malfunction of the answering machine.
Remedy: Check the operation of the power supply unit for increased voltage ripple.
NOVA RX-3610TP
Fault: There is always a call on the handset.
Remedy: Leakage in the optocoupler of the bell node on the base unit.
SANYO CLT-85KM
Fault: In the tube, with charged batteries, the discharge LED blinks.
Remedy: Check processor and trim circuits.
SANYO CLT-75KM
Fault: Reducing the radius of action.
Remedy: Check the output transistor in the base.
SANYO CLT-55.65
Fault: The low battery light is blinking, there is no connection, the batteries are normal.
Remedy: Check processor and trim circuits.
PANASONIC KX-T9080
Fault: A crackling sound is heard during operation.
Remedy: Bad contact in the connector between the RF unit and the board.
PANASONIC KX-TC408
Fault: The handset does not work, while there is a keyboard polling.
Remedy: Replace the D17 Zener diode on the power supply chip;
PANASONIC KX-TC900
Fault: The radius of action has decreased.
Remedy: Check the 903 MHz filter in the tube.
PANASONIC KX-T9500
Fault: Unstable handset-base connection, base-handset is normal.
Remedy: Defective tube noise detector. Replace the 455KHz filter.
PANASONIC KX-T7980, 9050, 9080, 9280
Fault: There is no connection between the handset and the base due to the drift of the transmitter frequencies.
Remedy: The trimmer capacitors in the RF unit are oxidized.
PANASONIC KX-TC408
Fault: Unable to tune the transmitter frequency.
Remedy: Replace varicap.
Fault: Dialing does not work.
Remedy: Replace the reed switch ..
ERICSSON GF788
Fault: When turned on, it does not find the station, long connection with the subscriber, when the case is squeezed, a noticeable improvement.
Remedy: Check the contacts coming from the card chip.
HARVEST HT-4
Fault: Interference during connection (in the form of rumble and noise).
Remedy: Check the capacitance in the 4700 uF power supply.
SIEMENS C35
Fault: Received signal strength indicator - 1, communication is unstable.
Remedy: Check the external antenna socket.
Already entered our life for a long time polypropylene pipes... They replaced metal and other plumbing systems. I want to tell how to solder polypropylene pipes yourself.
When I made heating at home, I decided to use polypropylene pipes, they are quite inexpensive and very easy to install. But before we tackle brazing pipes you need to purchase the required tool.
Those who love to travel and visit different countries have noticed that sockets and plugs are not the same everywhere. Also, when ordering various devices and devices, for example from China, it is proposed to choose various options: EU Plug, US Plug, UK Plug, AU Plug. How not to be mistaken in this? Let's take a closer look.
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Manufacturing defects and defects in such phones are practically absent and all breakdowns are formed only through the fault of the users.
