DIY TV repair electronics 23tb 307d

Compound : Radio channel 174UR3, synchronization 174XA11, the rest is discrete

Came to me with a problem - it does not turn on.
The neck of the picture tube cracked, in the breakage R38 47 kOhm. Replaced.

Now the problem is that there is no CSI at the output of 8 174XA11 (although at the same time the personnel is at the very least synchronized!).

I replaced 174XA11, tried to apply an input signal to the control system from 3USTST - it has exactly the same picture (they are made almost the same way). Obviously I don't understand something.

R2, R3, R4, R8, R9, C5 are OK. AGC is set normally. If I threw away the R10, nothing changes. The food is normal.

Here is a diagram and oscillograms. A test signal is sent to the entrance - two white stripes. Time base 20 μs / div. The first photo - Output 9 174XA11 - 0.5 V / div, the rest (collector and VT1 base) - 2 V / div.

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The first post is inaccurate. In the photo (from top to bottom): VT1 base, VT1 collector, input 9 XA11 (in the preview it shows in reverse order). It seems that VT1 is working correctly, I don't see any problems.
The C4 has a net 10.6V.
At pin 8 XA11, just zero - ground level.
Actually, the problem is that there are two bright stripes at the top and bottom of the image, and between them the line structure is visible in the image (see photo). The vertical size walks a little.
The second photo shows an oscillogram with a COC, 5 ms / div, 5 V / div, ground in the middle.
In the third photo - a frame saw, the top pin C5 of block A3,
5ms / div, 2 V / div, ground down.
On the C4 of the A3 block, the net is 7.8 V, on the C1 - 9.5 V.

It is noteworthy that the personnel period is 32 ms, i.e. the frequency is lowered.
Of course, the waveform on the KOK is incorrect, but this is a separate problem.

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Is your TV, radio, mobile phone or kettle broken? And you want to create a new topic about this in this forum?

First of all, think about this: imagine that your father / son / brother has an appendicitis pain and you know from the symptoms that it is just appendicitis, but there is no experience of cutting it out, as well as the tool. And you turn on your computer, access the Internet on a medical site with the question: "Help to cut out appendicitis." Do you understand the absurdity of the whole situation? Even if they answer you, it is worth considering factors such as the patient's diabetes, allergies to anesthesia and other medical nuances. I think no one does this in real life and will risk trusting the life of their loved ones with advice from the Internet.

The same is in the repair of radio equipment, although of course these are all the material benefits of modern civilization and in case of unsuccessful repairs, you can always buy a new LCD TV, cell phone, iPAD or computer. And for the repair of such equipment, at least it is necessary to have the appropriate measuring (oscilloscope, multimeter, generator, etc.) and soldering equipment (hair dryer, SMD-hot tweezers, etc.), a schematic diagram, not to mention the necessary knowledge and repair experience.

Let's consider a situation if you are a beginner / advanced radio amateur soldering all sorts of electronic gizmos and having some of the necessary tools. You create an appropriate thread on the repair forum with a short description of “patient symptoms”, ie. for example “Samsung LE40R81B TV does not turn on”. So what? Yes, there can be a lot of reasons for not switching on - from malfunctions in the power system, problems with the processor or flashing firmware in the EEPROM memory.
More advanced users can find the blackened element on the board and attach a photo to the post. However, keep in mind that you are replacing this radio element with the same one - it is not yet a fact that your equipment will work.As a rule, something caused the combustion of this element and it could “pull” a couple of other elements along with it, not to mention the fact that it is quite difficult for a non-professional to find a burned-out m / s. Plus, in modern equipment, SMD radioelements are almost everywhere used; The subsequent restoration of which will be very, very problematic.

The purpose of this post is not any PR of repair shops, but I want to convey to you that sometimes self-repair can be more expensive than taking it to a professional workshop. Although, of course, this is your money and what is better or more risky is up to you.

If you nevertheless decide that you are able to repair the radio equipment on your own, then when creating a post, be sure to indicate the full name of the device, modification, year of manufacture, country of origin and other detailed information. If there is a diagram, then attach it to the post or give a link to the source. Write down how long the symptoms have been manifesting, whether there were surges in the supply voltage network, whether there was a repair before that, what was done, what was checked, voltage measurements, oscillograms, etc. From a photo of a motherboard, as a rule, there is little sense, from a photo of a motherboard taken on a mobile phone there is no sense at all. Telepaths live in other forums.
Before creating a post, be sure to use the search on the forum and on the Internet. Read the relevant topics in the subsections, perhaps your problem is typical and has already been discussed. Be sure to read the article Repair strategy

The format of your post should be as follows:

Topics with the title “Help fix the Sony TV” with the content “broken” and a couple of blurred photos of the unscrewed back cover, taken with the 7th iPhone, at night, with a resolution of 8000x6000 pixels are immediately deleted. The more information you post about the breakdown, the more chances you will get a competent answer. Understand that the forum is a system of gratuitous mutual assistance for solving problems and if you are dismissive of writing your post and do not follow the above tips, then the answers to it will be appropriate, if anyone wants to answer at all. Also keep in mind that no one should answer instantly or during, say, a day, no need to write after 2 hours “That no one can help”, etc. In this case, the topic will be deleted immediately.
You should make every effort to find a breakdown on your own before you get stumped and decide to go to the forum. If you outline the entire process of finding a breakdown in your topic, then the chance of getting help from a highly qualified specialist will be very great.

If you decide to take your broken equipment to the nearest workshop, but do not know where, then perhaps our online cartographic service will help you: workshops on the map (on the left, press all buttons except “Workshops”). You can leave and view user reviews for workshops.

For repairmen and workshops: you can add your services to the map. Find your object on the map from the satellite and click on it with the left mouse button. In the field “Object type:” do not forget to change to “Equipment repair”. Adding is absolutely free! All objects are checked and moderated. A discussion of the service is here.

The electronics of the VL-100 did not turn on. Then I fixed it. There were problems with the microcircuit, which is responsible for the deflector.

Hello. I was given a takoyzhe TV ELECTRONICS 23TB-316D FOR SPARE PARTS YANENY I UNDERSTAND IN ELECTRONICS. SWITCHED ON THE TELIK NOON DOES NOT SHOW, ON THE SCREEN A NARROW HORIZONTAL STRIP. HOW MUCH I UNDERSTOOD THIS SCAN DOESN'T WORK.

That resistor is installed on the power supply, apparently it regulates one of the voltages.

I had one for a while, I was 14-15 years old. I don’t remember whether relatives or friends gave it for repairs or something else.Truckers carried this and similar TVs in cars.

this is not a diode but a high-voltage pole

Kadyr Nazarov the transformer itself does not burn, it seems to me that the reason lies deeper than you think.

Turn to this person, he has more experience.

It is not necessary to wait 10 minutes. You just bring the insulated wire attached to the chassis ground to the high-voltage part and that's it)

Schemes of televisions. Datasheets (datasheet) of foreign microcircuits and transistors. Books for radio amateurs. Free download.

now to him some kind of spectrum))

we only had this black

DEX lt-3251 TV does not turn on the light is blinking. what could be? and I can not find the circuit for the power supply (

It would not have been better to disassemble this telly for parts.

Now in modern workshops such boxes are not made, and you can find spare parts for it if you only find the same lamp box in a dump and unscrew the microcircuit from it and solder it into this old TV set

The multiplier gives out so much 3.2 kV, it should give out much more than the transformer itself

purchased multiplier from a vl100 telly with a diagonal of 16 cm and an anode voltage of 6 kV
repaired this in the 90s, the diode in the multiplier was broken and one frame scan transistor burned out
and I thought about any details except the multiplier, tk. considered this thing quite strong judging by the telly with picture tubes 61lk, but it was out as it turned out

on the power board at the back there is a voltage adjustment. should be 11.3v. and the TV is not a factory one. bare self-assembly. frame without electroplating. one speaker for savings. boards without loops. the deflecting coil from the monitor and not the native one is so cheaper. The soldering is crooked. but everything works!

The ROTEX 2176 TV shows a blue screen! I took it apart, cleaned it from dust, began to show all colors except green! green turned black! After working for several days, the screen turned blue again, sometimes it breaks and shows normally 5-10 seconds with all colors! then blue screen again! (not in the sense that just blue - but you can watch films and programs! but just all colors are blue) what could it be?

brother, you can connect a DVD to a small electronics TV and how to do it if you know they say through the prefix dandy thanks in advance.

on the TV, the electronics resistance is the one that switches the channels to how much it should be a lump or ohm

2:00 high is not heard, there is none

on TB, you can not climb after disconnecting from the network for 40 minutes

trimmer resistor on the power supply unit to adjust the output voltage

If I was shooting for myself, why did I put it on YouTube?

You talk about a video lesson and then it’s like you don’t have a shit at all to climb into the technique of logic

Hello dear forum users.
Help on the diode bridge of the TV, the names of the diodes are needed. I found the scheme on the site, but the quality is poor and the name of the parts is not visible.
Maybe someone has a diagram, please take a picture.
Thanks in advance.

Looking for problems out of the blue?

Is it a threat or an answer as a result of an inadequately asked question?

Which ones do you have and choose from them for a current of 3-5 amperes. And there seem to be KD202. And leave the forum. DO NOT ASK SUCH QUESTIONS HERE.

And that they were dismantled and drunk? And everything else is in place, or will the next questions be about black and colored three-legged parts?

- this is the BLUNT of a client who imagines himself to be a master.

The schemes are in Google and ANY master knows WHAT to put into this primitive BW-TV.

- no, 1n4007 (or even better - 1N5402), relatives there kd209, kd243

Ruslan, are you confusing anything? Put high-voltage diodes on 12 volts, and their current is too small.

and what's the difference - 01-07 - the difference is in reverse voltage, forward current - 1: 1
There TV “eats about 0.7-0.8 amperes from the force. power supply - not simple - PWM.

power supply -simple-power transformer 220v / 12v -diode bridge-filter-stabilizer on KT837

It is PWM and synchronized with horizontal scanning, and diodes
KD208A

https://my.housecope.com/wp-content/uploads/ext/2254/download.php?id=10093
Well, there is no PWM on this circuit.

Although I do not exclude that PWM and the diodes you indicated were used in TVs of the latest releases.

I saw the synchronization, so that the stabilizer is made on PWM, and PWM on transistors? I'm in a pancake.

Supplement to "Repair of TV Electronics 23TB-316D":

More pictures:

In this video I will show you how to repair TVs, or rather, how I repaired an old Soviet TV Electronics 23TB-316D of a portable type found on the street.
The main problem was the voltage multiplier, I replaced it and everything worked.
So the video came out of the category “My Finds” to be repaired at the same time. ... ...

In the old days, when buying a TV, it was accompanied by a technical passport and a circuit diagram of the device. Now this is not the case, and if we need a circuit for any device, we just look for it on the Internet. If it is not found, then we proceed with the repair relying on experience and knowledge. For novice radio amateurs, when repairing a device and not having a circuit for this device at hand, it is rather difficult to carry out repairs.

What is she like? The basic electrical diagram of the TV is a detailed image of all elements with their reference designations and electrical connections between them. Here, for example, is a schematic diagram of the Electronics 23TB316D TV.

It is also important to be able to use it, and for this you need to know the symbols of radio components on the diagram. The positional designations of radioelements help to understand the scheme and divide it into blocks. It looks like this, details with a designation starting with one digit C402, T401, R432 - will refer to one functional block, and C502, T511, R522 - to another. This is done so that you can see what details are related to the vertical scan, line scan or power supply. I already mentioned this in the article on the structural diagrams of the TV.

The basic diagram of an LCD TV, LCD, color and tube TV will differ, it will only be used in newer models, newer elements. On the schematic diagram of a tube TV, you will not find microcircuits, but on the LCD diagram you will find lamps and a kinescope.

If you need a schematic diagram of a Philips TV, it is also important to indicate the model of the TV receiver, for example Philips 14PT1354 / 58. This circuit will fit several more models, such as Philips 14PT1565 / 58, 20PT1354 / 58, 20PT1554 / 58, 21PT1354 / 48 and that's not all! In this case, it will be enough to search according to words, Philips 14PT1354 / 58 circuit. There is another option for searching by chassis (if you know it, of course), in this case it is chassis L9.2E, but you can find this number on the board (although it is not always far from elektronika23tb316d).

• griha09
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Hello everyone! I decided to restore Halo 23tb-307, there is sound, instead of a picture, this is such nonsense. What is the reason? In which block of the TV to look for a solution?
I also want to connect a digital TV set-top box to it for fun. The question is where to solder the tulips? As far as I understand, the braiding of the "tulips" is on a common wire. Central video - to the video amplifier input. The central sound is at the ULF input. Right?

• master_tv
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If you have a defect as in the video, then most likely the general synchronization is broken or a malfunction in the power supply unit. Check the stability of all voltages. Apply the test TV signal of the IF to the XS1 input of the A2 module and check the operating modes of the sync pulse selector (oscillograms 4 and 5), vertical (oscillogram 10) and horizontal sweeps (oscillogram 6), check the trimmers and capacitors (especially electrolytes) in these stages.
And you can connect a TV set-top box to your TV only through an RF modulator (you can use a modulator from the dendy set-top box or look for something on the Internet).

It's a shame to throw out a TV that costs 50,000 rubles and more, on the contrary, a cheap LCD panel is sometimes easier to buy than to replace the matrix. This takes on significance in private companies, the staffing table contains a master's cell. It is not surprising that there is a keen interest in repairing TVs with your own hands, the breakdown may be insignificant, the gain is obvious. How not to be electrocuted, not to break the device? We plan to discuss with today's review, we will list the main types of faults.

The percentage of models with a cathode-ray tube is large. It is logical to start with them to consider how to repair a TV, because switching power supplies are considered an integral part of any equipment. Liquid crystals, OLED (organic diodes), plasma. Scanning chips use similar principles. The way of building the image is different, but the element base is similar. Consequently, do-it-yourself TV repair moves along the beaten path.

The equipment contains fuses. Let's open a secret: if a force majeure situation (lightning strike, power surge, equipment drop) happens, the protection should break. Almost the end catches up with the microcircuits. Start with the fuse. Of course, if the equipment is devoid of signs of life. In normal mode, the current through the fuse is zero, the repair specialists came up with the fact, put it into service. The burned-out part is removed, a 100-watt light bulb is connected to the terminals. The resistance is relatively high, it will serve as a good current limiter, the electrical circuit will slow down further to burn out.

Note. According to Ohm's law, the power released by a section of a circuit is proportional to the current. By limiting the value, we will avoid burnout of radio components. Actually, this is done by supplementing the circuit with limiting resistors. The light bulb serves the purpose of indication, makes it clear if an electric current is passing. The spiral is heating up, we see the light.

In normal mode, the light will blink, then go out after turning on the TV. Moreover, the device with such an additive works slightly incorrectly. There are two parts that often burn on CRT TVs:

1. The diode bridge rectifies the current. With a sharp increase in consumption, one branch burns out. Usually two diodes fail. You can determine the suitable ones by dialing. The diode current flows in one direction, in the other the valves are locked. The circuit triangle indicates where the current is going. According to the concepts of circuitry, the current always flows from plus to minus. Accordingly, place the electrodes starting the dial tone.
2. The second curious detail is a posistor operating on an inductive loop, the task of which is to remove the potential from a cathode-ray tube. Otherwise, a characteristic rainbow appears on the screen due to the violation of the movement of electrons. A thermistor or a loop may burn out. It is easy to check the circuit. You will need to turn off, then turn on the power. If the lamp that used to be on is now out, the problem is in the potential removal circuit. You can test the device, for a while it will be able to work normally without a loop.

How to understand whether the posistor is out of order or the loop is burnt out? First, measure the resistance. The posistor has four inputs. Two form a heating circuit, two - remove the potential. The resistance between the first pair will be 300 - 600 ohms, between the second - units of ohms. If you turn off the outputs going to the CRT demagnetization loop, we will exclude the section from work. The verification technique is simple. If the lamp is on with the loop, but not without, then you will have to look for a new lace. Visually - a thick wire that surrounds the cathode ray tube around the perimeter. To check the posistor with 100% accuracy, take the trouble to evaporate. After turning on the power, observe the action of the light bulb.

For reference. You cannot keep the equipment turned on for a long time with a light bulb that replaced the fuse. The device is defective, there is a large current in it.It is enough to turn on for a second to understand whether the light is on or not. Then unplug the TV plug from the outlet. It will allow you to protect the serviceable elements of the chain from the unusual load.

What else will burn? In the power supply at the input there is a large capacitor, next to it is a power transistor. Both parts are ringing. The transistor breaks through the source-drain transition, although other options are possible. If it is noticed that half of the diode bridge has burned out, it speaks eloquently: the fuse has failed. The type of breakdown of the TV indicates: there is still a malfunction inside. But it has already led to the failure of one branch of the diode bridge. Carry out the diagnostics until the lamp refuses to light up at all. The key sign of a properly working TV is a characteristic hum, which indicates that the line scan has turned on.

Forgot to give general instructions on how to repair your TV. The main board is dismantled for convenience, leaving a chance to get an electric shock even from the switched off device. It seems that no one has died yet, they got burns. You will need to discharge the cathode-ray tube electrode. Located under the rubber gasket. Without touching the metal parts with your hands, pry the rubber with a screwdriver, swinging from side to side, remove the electrode. Discharge the rod onto the body. If you see a ground loop nearby, it is better to go to it. It is clear that for a successful procedure, you need to have a European socket with correctly connected terminals on hand.

Clicks will be heard during discharge. Continue to touch the contact while the phenomenon is observed. Any modern TV set has electronics assembled by one board, which controls the operation. Many radioelements are visually assessed for their integrity. Defective capacitors swell, resistors (active elements) turn black. Darkened resistance sometimes stays good. The defect clearly indicates: the radio element closes the circuit of the broken element.

LCD TV repair is similar to the case of CRT models. The posistor is, of course, absent. It's easy to understand the cause of the backlight breakdown. LCD TVs use two types:

• discharge gas lamps;
• organic or LEDs.

Gas lamps don't look like cousins ​​hanging from ceilings. Rather white straws. To check the power, remove the back panel to see the wires going into the matrix. Carefully disconnect from the connector, taking a working lamp, check the functionality. It happens that a number of discharge light sources are occupied by the illumination. Take the trouble to remove the matrix, turn on the TV, see which lamp does not work, replace it.

The installation scheme of the illuminators is different. In some TVs, you just need to pull out the lamp from the end without disassembling the matrix. The wires come in from both sides, each covered with a rubber gasket. The protective elements should be pushed aside, the lamp should be evaporated. Installing a new one takes place in the reverse order. Try to choose one that is equivalent in size to the replaceable one. The location of the lamp is lateral, less often the top. It happens that there are two or more illuminators. If a vertical or horizontal stripe appears on the matrix, the scanning electrode most likely burned out. Try to turn on the device with a different, known good matrix to check the assumption.