DIY repair Al1411dv

Details: al1411dv do-it-yourself repair from a real master for the site my.housecope.com.

When the battery is connected, the BOSCH AL 1411 DV charger imitates activity - the green light starts flashing, depicting the charging process, it can flash for 5 and 10 hours, then it lights up constantly green - like charging is over. In fact, nothing is loaded. The voltage at the terminals when connected corresponds to the battery (that is, the charger does not give anything). At the output from the transformer by zeros.

There are no signs of burning on the board.

It is forbidden to write answers that do not carry any benefit for the questioner from the series: “take it to the service”, “contact the ASC”, “unprofitable”, etc. Such answers will be considered rating cheating, the answers will be deleted, and the account will be blocked.

If you undertake to help people, answer fully. Explain why, if you recommend, for example, to reflash the phone, then write how to do it. If you write that the repair is unprofitable, explain why.

WorkBlog about electronic devices, electronic components, electronic devices, repair of equipment and electronics, solving developer problems. The advertising income of the blog (if any is formed!) Will be transferred to motorcyclists injured in road accidents, motorcycle accidents are painful and scary.

A good friend called here and says - he was charging Shurik, the plugs were knocked out, the charger is intact, the parts are clean, but it does not work. Lan, take it.
I brought it, I open it, I assess the scale of the disaster. Gary doesn't really. I hang a multimeter on the drain-shutter of the key in the BB-part - a breakdown. Leave it, Andryush, it's a pitchfork.
This is the first part of the repair, and then there will be another and the second:

Video (click to play).

A wonderful memory worked immediately and without whims. I immediately climbed onto the drain, I had to make sure that the STD7NM60 did not throw back its hooves. The voltage margin, it turns out, is almost non-existent. 540V in impulse, frequency 130 kHz.

Final run with battery. OK

Well, the scheme of the hot part with all the giblets, some other-speaking person helped me a lot.

Bosch is a fat failure for all this crap. For varnish, shitty components and a stupid charger that they blinded from this shit. Judging by the descriptions, these chargers fly every first.
I am also grateful for the psto on the “Monitor”. I'll bring it here. Found after repair 🙂

Here are some more recommendations for this charger -
his board is very bad, so any attempt to solder the parts, the signet flies off before you heat the tin on the leg.
I adapted to change the parts without soldering their ends - I cut the cuts at the root and solder new ones to their legs right from above -
from below, ideal factory soldering, also with tranzuk 3904 (instead of it, the smd version is perfectly soldered), diodes and field,
the board is varnished so that soldering is very problematic,
another 3.6 ohms stands between a large condo and a radiator - it is difficult to bite it out, and I solder new ones directly from the side of the tracks -
again, it’s very convenient to get a smd summary, there just the paths pass nearby, I clean it with a scalpel, a puddle and plant a smd summary,
only it is necessary to carefully remove the soot from the plzma and varnish of burnt parts from the front side with a scalpel. “

The colleague's problem is solved, the deadline is already a long time, but let the newcomer contribute, for posterity. I also ran into the same problem with TS. Thank you for coming across this forum and this thread, here's my situation:
In the first two photos, the same board, the same charger:
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In the following photos, a light resistor closest to the microcircuit, R5 - 100 kOhm, according to your schemes. Pay attention to it, I needed to solder and check all the transistors, diodes, thermistor. until I noticed that under the layer of varnish there is no leg for this resistor.
[

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This photo clearly shows the marking of the microcircuit, I don’t know who needs it or will help, but this has been asked more than once:
[

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In the last photo, I showed that I changed the thyristor 208 to 408, there were no other options in the store, I will return my native one:
[

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Thanks to everyone above for the advice and help!

Hello. I’m glad that the problems with the chargers were resolved. And I have a problem with the battery. It died, it doesn’t hold a charge. The battery voltage is 14.4V. I thought I could put 4 LiIons instead. Can anyone suggest a charger for these purposes that needs to be redone, a regular Bosch AL 1411 DV.

rus38 wrote:
.And I have a problem with the battery. It died, it does not hold a charge. Batteries are new metal hydride at 160 rubles / piece. The battery voltage is 14.4V. I thought I could put 4 LiIons instead. Can anyone suggest a charger for these purposes that needs to be redone, a regular Bosch AL 1411 DV.

It's not that easy (IMHO).
By the maximum voltage during charging, the cut-off can be found, and the finished board can be soldered into the charge, and it is difficult to find the minimum for such currents for a screwdriver. Is it just a compact voltmeter to watch yourself and if anything run to charge.
In addition, you will need batteries with good current output and with the same parameters. I’ll roughly calculate, banks of 8, controller 20, voltmeter 10, total 54ue. You need 2 batteries, one is always not enough. “Lithium” cannot be soldered, there is a big chance to overheat, only contact welding with nickel ribbons, you are unlikely to do it yourself, you need to carry it to specialists for repacking, this is still a lot. Think for yourself.

rus38 wrote:
.And I have a problem with the battery. It died, it does not hold a charge. Batteries are new metal hydride at 160 rubles / piece. Battery voltage 14.4V.

Battery brand? Did you measure the voltage at each bank under load?

The fact that the battery died is undeniable. I didn’t measure the voltage on the banks under load, but the self-discharge is simply amazing. In a week, the entire charge evaporates. Yes, and the charged one does not pull very long. .What's the point of putting new ones with half-killed ones? There are more capacious “Minamoto MH-3000 SC / HP” on sale, you can switch to them. For soldering Li-Ion, you can try the Rosé alloy so as not to overheat. banks, it's not a pity if they burn.

rus38 wrote:
I thought maybe put LiIon 4pcs instead.

look, maybe this option will be more useful ” > still uses the alteration.

An interesting idea. It turns out a native charger in the trash, buy a Chinese one, redo the battery. Is it really not possible to transfer the charger itself? .3 batteries in the battery.

rus38 wrote:
Isn't it possible to transfer the charger itself?

Yes, it can also be redone, but you will need to buy another balancer and a 14-volt power supply

rus38 wrote:
Connectors B1 and B2 are the most incomprehensible and mysterious.

these are balancing plugs, they monitor the voltage on each of the 3 batteries in the battery

Reworking chargers and more

rus38 wrote:
It turns out a native charger in the trash, you buy a Chinese one, you remake the battery.

With “lithium” (a capricious and capricious young lady), “jokes” are bad, he does not forgive, like the good old “cadmium” overcharge with overheating or overdischarge.

That's why lithium is weighted with a balancer with temperature sensors. And such controllers are built into any lithium battery (phone, laptop, fotik, Shurik, etc.).

Lithium cannot be operated without “brains” for both charge and discharge.

On cadmium, if a recharge has already begun due to too long charging, it heats up a little, and if which bank of the entire bunch was discharged more than others or discharged, or the capacity is different, the excess energy is relatively safely converted into heat and safely distributed between the cans and that's all, there's nothing to be afraid of.

And lithium, if it is recharged, there will be a fire or a boom, and if you recharge it a couple of times deeply, death in the form of a premature and inevitable loss of capacity.

So, in order to insert a battery and a charger and forget, and not touch it and not look and not be on duty near it with a voltmeter, lithium should be automatically controlled by checking the personal voltage on each bank this time (this is a cut-off for maximum voltage) and thermal sensors - it's two.
In smart chargers, there is also a balancing circuit, which during the charging process regulates the charging current on each bank, depending on its degree of wear.
(Although in Bosch the baby there is no such balancer during charging, as in most chargers for Shuriks)

And during operation, the controller makes sure that there is no voltage drop again on each bank, a little sharply cuts off the load.

Thanks for the detailed explanation. Q: Do balancing chargers have temperature monitoring? In my opinion, they don’t even look at the temperature sensor at all. Maybe the electric brains can glitch and limit the current on the sick bank, then the temperature sensor would be reinsured. Or what kind of resistor can burn out in a balancing circuit and it will completely thrash around. Or is it all unlikely?

rus38 wrote:
do balancing chargers have temperature monitoring?

rus38 wrote:
Or is it all very unlikely?

lithium phones

Reworking chargers and more

My traffic burned out on Bosch AL 1411 DV iskat 15v-1A or 18v-1?

Charger Bosch AL60DV 1419 7.2-14.4 v, 14.4 v 2.4 Ah is written on the battery
I insert the battery (voltage on the battery is 14.74) - the diode does not light up and does not blink.
If “” acc put on charge, and shorting the K-E at V7 “” - 18.34 v

all contacts are soldered. whole diodes. temperature sensor on a 6.08 kOhm battery, I don’t know where to dig.

On TYN 208, it goes directly from the trance, and not as in the circuit - through diodes!

/ the diagram looks like the one drawn above - does not fit my .. /
Measurements: - on the minus
1- 7,5
2- 0
3- 0
4-(-0,9)
5- 22,8
6- 4,5
7- 4,9
8- 4,9

Balu0389 wrote:
Charger Bosch AL60DV 1419 7.2-14.4 v, 14.4 v 2.4 Ah is written on the battery
I insert the battery (voltage on the battery is 14.74) - the diode does not light up and does not blink.
If “” acc put on charge, and shorting the K-E at V7 “” - 18.34 v

all contacts are soldered. whole diodes. temperature sensor on a 6.08 kOhm battery, I don’t know where to dig.

On TYN 208, it goes directly from the trance, and not as in the circuit - through diodes!

/ the diagram looks like the one drawn above - does not fit my .. /
Measurements: - on the minus
1- 7,5
2- 0
3- 0
4-(-0,9)
5- 22,8
6- 4,5
7- 4,9
8- 4,9

Ivan_90, For those who have the same question, I will answer (better late than never): The transformer is exactly 18V at the output. Power 28W (declared on the charger case) Bosch AL1411DV, so the current should be approximately 1.5A. In short, the transformer is 18V 1.5A output. Moreover, the use of a low-frequency transformer (linear PSU) in this charger is not accidental, it charges not with direct current (DC), but with a pulsating voltage of 100Hz (double half-waves 50Hz taken from a 220V city), without a smoothing capacitor. According to some reports, this mode of charging Ni-Cd batteries is quite effective.

I'm not sure if the transformer burned out. It may have overheated and the thermal fuse has tripped. In this case, the transformer can be restored! The thermal fuse in this transformer is wound to the winding from the outside, if you remove the cover from the windings from the 220V input side, then you can try to replace the thermal fuse. The thermal fuse leads are connected to the extreme petals of the transformer from the 220V input side. There must be resistance between the extreme petals (DC)

0 Ohm - thermal fuse. Winding (primary) is connected to the right and middle petals - resistance (DC)

90 Ohm. The 220V cord is soldered to the left and middle petals. If the primary winding (middle and right petals) ring, and the extreme petals do not ring among themselves (resistance is infinity), then you just need to replace the thermal fuse! It is better to restore the native transformer than the one that was found.

There is some confusion about how to correctly name the TYN208: call it “SCR” or “thyristor”. The fact is that in the USSR, the entire family of controlled diodes, including dinistors, trinistors and triacs, was often called thyristors.However, the word trinistors probably did not take root and they began to call the thyristor what is called “trinistor” in the old writer. And SCR (simply SCR) is the marketing name of a “trinistra” or, as it is more understandable, a thyristor, i.e. controlled unidirectional diode with unlocking contact (three pins).

Help with a subject.
Symptoms: Insert into the outlet - the indicator lights up constantly.
You connect the battery - the indicator will blink and glow constantly again. (When it was working, it blinked until the end of charging, then it glowed constantly.)
Accordingly, the battery is not charged.

The transformer is working, the diode bridge is normal.
There is no voltage at the terminals (without a connected battery). (Is it supposed to be? If the third pin is hanging in the air, should there be voltage?)
The battery was temporarily taken away, I can’t check the voltage under load.
Does it make sense to check the TYN208 thyristor (V5 on the radiator) or is it more likely to be in control?

Chip 6HKB 07501758.
Visual inspection revealed no problem. There was a suspicion of poor soldering in V5, soldered - the result is the same.

Charging is a bit similar to BOSCH AL1419DV, here is the diagram: ”>
Here is the diagram:

Available tools: multimeter, soldering iron. There is no oscilloscope.

Kostroma Jedi Forum → Flea Market → BOSCH Screwdriver Charger Repair Needed

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Charger AL 1411 DV failed. Does anyone know if it makes sense to repair it, how much it will cost or is it better to buy a new one?

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Kostroma Jedi Forum → Flea Market → BOSCH Screwdriver Charger Repair Needed

If a DVD player breaks down, you don't have to throw it away or take it to a workshop and pay money for repairs. You can disassemble and even repair the device with your own hands.

The player consists of a case with a disc tray. On the front panel of the case are located: a status display, player control buttons, on some models there may be connectors for connecting a microphone, headphones, a flash drive. Inside the case, everything is much more interesting.

Briefly about the main components of the device.

This is the main element of the player. It consumes electricity from a switching power supply.

It is used to read information from the media. A wide flexible cable connects the reading head to the main board. All disc media has a mounting track that is required for proper operation. It is located in the center. When a disc is loaded, the laser moves to the center to read that track. If the reading was successful, the presence of the disc is established, and only after that the rotation motor is turned on, and the disc starts playing.

The motor communicates with the processor through a driver. The disk rotation speed depends on the processor signals.

This is a microcircuit that receives commands from the processor and controls the operation of the spindle drive motor, laser lens focusing coil, laser reader movement motor, tray loading and unloading motor.

“So many devices and wires! I'd better take it to the workshop!" - you will say with horror, clutching your head. But! Don't rush to spend money. There are such breakdowns that can be easily identified and repaired with a conventional screwdriver.

There could be many reasons for this. Consider the most elementary and common. Let's remove the cover of the player and diagnose the power cord for internal damage. To check the operation of the multimeter, turn it on to the resistance measurement mode. We connect the probes to each other. If the device is working, zeros will appear on the display. We connect the open probes to the cord. One probe to the cable contact at the junction with the board, the other in turn to one of the plug contacts. If the ohmmeter outputs up to 3 ohms, the wire is undamaged. If more, then there is a breakthrough in the core, and the cord must be replaced. If the multimeter does not respond in any way, then the contact on the plug and on the opposite end does not belong to the same core of the electrical wire.It is not recommended to use the multimeter in continuity mode, as it works in the range from 0 to several hundred ohms. The next step is to inspect for dust and swollen capacitors. We clean the dust, change the capacitors. If no visual problems are found, and replacing the wire does not change the situation, take the player to a workshop.

The video below shows how the multimeter works.

Consider the main causes of failure and how to deal with them.

Causes: the laser head is dirty or the laser is out of order.

The contaminated head is blown with compressed air using a conventional rubber bulb. The objective lens is wiped with a cotton swab moistened with alcohol. Solvents must not be used. You need to wipe it very carefully with light movements. If cleaning is not enough, the head must be replaced.

Charger Bosch 2.607.224.392 suitable for Bosch NiCd and NiMH batteries with voltage: 7.2 V; 10.8 V; 12V; 14.4V. This is a fast charger that has Delta Voltage charge control. At the end of the operation, a sound signal is produced. The ability to use this charger with different batteries expands its scope.

The manufacturer reserves the right to change the characteristics, appearance, packaging of the goods and the place of its production without notifying the dealer.

This information is not a public offer

For a long time I was looking for a charging circuit, I did not find a Bosch AL1450DV charging circuit (only after repair).

Charging green LED is off

Inside was a power supply more complicated than a computer

I checked all the transistors of the microcircuit, I did not notice any special deviations. Capacitors of high quality are all normal with ESR, too, below acceptable.

I burned the key transistor - STP5NK80Z - STP5NK80ZFP N-CHANNEL 800V - 1.9W - 4.3A TO-220 / (TO-220FP-less power) Zener-Protected SuperMESH ™ Power MOSFET The presence of the letters FP in the marking means an insulated case (it may be important when using a radiator). The transistor is definitely a MOSFET. Transistors that are marked 5N60, 5N80 are suitable for replacement. The BUZ90 and the rest, for example from the IRF series, are also suitable.

It was a resistor of an incomprehensible value, Who knows what?

The standard scheme of the pulse charging regulator on the UC3842 is almost the same as that of the Bosch AL1450DV

Power Resistor 220V d.b. order 75-100Kom , it heats up quite strongly, it is better to put 2 W (put some 2 W about 80Kom).

Replaced UC3842 (can be replaced by UC3843), Optocoupler CNY17F-2, LM358.

There was a suspicion of ms 16 legs. But no one could find any diagrams or datasheets for it. Search for .pdf on m/s 6HKB 07501758, but to no avail. 6HKB07501758 only found out that the manufacturer is STM …..

Here's what it says on the case:

?HUI 0750 1833 /1 line
B GK390TT /2 line
VM99CHN /3 line

0750 L9L4 /MKL
L GK8080LW
V6 99 CHN

Maybe someone knows what this ms is and how it can be replaced?

MAX712/713 MAX8213/8214 (something similar?) - 16 feet

ICM7556 -14 (8) legs is not right

With Bosch chargers, everything is quite funny))) they have microcircuits by special order ...

I advise you to pay attention to m / s MAXIM2003 (similar to bq2003). On it you can embody the necessary charger. Or max713. In KIT and ready to give.

Someone says that 6HKB07501758 dies when a dead battery is connected, but this is not our case.

I didn’t want to blow up anything else, so I connected the charging (according to the method) to 36v changes, having previously soldered another 20Kom in parallel to the ill-fated resistor. The unit squeaked and blinked a green diode. Nothing got hot, no short circuits. We solder 20Kom and plug it into the network - everything works, the resistor heats up noticeably, as it was intended.

Lastly, a little extra. battery information

I assume that the 3rd contact is a thermistor to control the temperature of the battery. This is the 2nd end connected to the minus. Resistance 10k
At the moment, I want to know what is in Bosch's native batteries.Most likely a thermistor, because the contact is signed “NTC” on the board. I hung a constant resistor of 10 kilo-ohms between the third leg and the minus of the battery - the flight is ordinary, it charges. Unfortunately, there is no Bosch battery at hand - can someone look at the type of thermistor and post the value or photo of the part.
accs are different:
12v 1.2Ah (2003) = 6.9kOhm
12v 1.2Ah (2003) = 7.7kOhm
12v 1.5Ah(2008) =7.8kOhm
14.4v 1.5Ah(2007) =6.1kOhm
12v 1.5Ah (2005) The resistance of the resistor is 6.19 kiloOhm, it stands between “-” and “C”.

In Hitachi, the temperature sensor turns off charging at a resistance of 2.85kOm. You can call the rest of the batteries, rather than the contacts are the same
Shutdown occurs from the temperature of the battery cans (+55″С)

More
Let's compare the characteristics of 2 memory:
Bosch AL1419DV charging current 1.9 A -1100 r.
Bosch AL1450DV charging current 5 A - 3000 r.
The voltage of the rechargeable batteries is the same: (7.2 ... 14.4 V) both are suitable for charging NiCd and NiMh.
Just 1450 will charge a battery with a capacity of 2.6 Ah in 40 minutes, and 1419 in 1 hour 45 minutes.

cash purchase price

BOSCH service center address:

Novosibirsk, st. Sibrevkoma, 2, of. 02

1. Warranty conditions

1.1. Warranty service and repair of Bosch, CSTBerger power tools and Skil measuring equipment in compliance with the requirements and standards of the manufacturer are carried out on the territory of the Russian Federation only in branded or authorized service centers of Robert Bosch LLC.

1.2. The service department of Robert Bosch LLC considers warranty claims only if the original warranty card and the sales (cash) receipt, invoice confirming the date of sale are correctly filled out.

1.3. The warranty period is calculated from the date of sale to the consumer and is:

— professional tools and measuring equipment (blue case) — 12 months; when registering on the site within 4 weeks from the date of purchase, the warranty is extended for another 24 months;
— household tool (green case) — 24 months; when used for professional purposes, the warranty period changes to 12 months;
— measuring equipment Skil — 24 months; when used for professional purposes, the warranty is void;
— CST/Berger: depending on the type of tool, the warranty is from 12 to 24 months; full information on the terms of the guarantee is available on the site. In case of disputes, the period indicated on the website is considered correct.

1.4. During the warranty period, the following are eliminated free of charge:

- damage caused by the use of low-quality material;
- defects in the assembly, admitted through the fault of the manufacturer.

The service life of Bosch, CST/Berger power tools and Skil measuring equipment is 7 years.

2. No warranty

2.1. On mechanical damage (cracks, chips, scratches) and damage caused by exposure to aggressive environments, high humidity and temperatures, the ingress of foreign objects into the ventilation grilles of power tools, as well as damage resulting from improper storage (corrosion of metal parts). On electrical cables with internal and external mechanical and thermal damage.

2.2. Tools with malfunctions caused by overloading, non-observance of the instructions for use or improper use, use of the tool for other purposes or due to the use of improper equipment.

2.3. On the natural wear of the tool (complete depletion of the resource, severe external or internal contamination).

2.4. Parts subject to natural wear and tear.

2.5. For interchangeable accessories (chucks, collets, tires, sprockets) and working equipment (saws, drills, cutters, saw blades).

2.6. For tools that have been opened or repaired during the warranty period outside the Robert Bosch Service Center or an authorized service center.

2.7. To a tool with a serial number removed, erased or changed.

2.8. For preventive maintenance of power tools (cleaning, washing, lubricating, etc.).

2.9. On battery packs that have fully exhausted their resource.

3. The work of the service center and the signature of the client

Some power tools and measuring equipment require periodic maintenance; this is stated in the instructions for the product.

The work of the maintenance workshop is carried out in accordance with the current rates of the service center. All faults identified during maintenance and covered by the warranty are eliminated free of charge, and non-warranty defects are eliminated in agreement with the consumer in the prescribed manner.

The client's signature is a confirmation that the client is familiar with all the clauses of the warranty conditions, instructions for the tool, understood them and agrees with them.

There was nothing to do - it was necessary to save the device, and curiosity worked, but what is the problem (you understand me), so I settled myself comfortably and warmed up a hundred-watt Soviet soldering iron (alas, in the whole village there was no more convenient soldering iron).

After half an hour, the soldering iron warmed up like an oven. The player itself showed no signs of life. After opening, it turned out that the fuse had blown, the electrolyte after the diode bridge at the power input and another electrolyte on the 12 Volt bus, already at the PSU output.

Since the components were strained, the fuse was wrapped in foil and put in place. The electrolyte on the 12 Volt bus with a capacity of 1000 microfarads was replaced with 470 microfarads, and the capacitor was found in the power supply from the SEGA console.

The first electrolyte - on the rectifier, turned out to be fully functional, only for some reason it swelled up, it was not replaced.

After turning on the player, it started working like new, but after examining the PSU board, it became clear that the unit was working abnormally - an incomprehensible overheating of the diode bridge, some limiters and even capacitors. I left the player turned on for an hour - the heat dissipation turned out to be stable, who knows, maybe initially it all got terribly hot, but it works very well. Best regards - AKA KASYAN

Everyone knows the situation: we insert the disc into the DVD player, but the disc is “unreadable”.

Two possible reasons:

2. Malfunction in the DVD drive.

On the example of DVD HYUNDAI consider one of the options for repairing a DVD drive with your own hands. At first, the DVD “stopped reading discs”, and the malfunction either manifests itself or disappears, and as a result, it stopped working altogether.

First, we always check the output voltages from the power supply. Is the voltage normal? Next, we look at the disk drive, for this we unscrew it and disconnect all connectors.

We visually check the connectors, cable, soldering, etc.

If the visual review did not give anything, move on.

Next, you need to ring the cable that goes from the board to the head.

During operation, the drive head constantly moves from place to place. As a result, it turned out that the four extreme conductors of the loop were in a cliff, the rest were also ready to come off just about. Pry off the insulation with a needle. You can see the broken path here.

If there is a break at the very beginning or end of the cable and its length allows, then you can carefully cut the tip of the cable with scissors and insert the cable into the connector.

But sometimes it is useless to repair the cable, it is constantly in operation, moves and bends, if soldered, then after a while it will break again. We must change. That's just the problem to buy exactly such a train is very difficult. But there was a way out! At hand was an old unusable drive from the computer. True, the train from it is wider and longer, but the distance between the conductive lines and their thickness is the same.

But it's even good that it's longer, because. will bend less, and there is enough space for it. Contacts fit perfectly, one to one!

We accurately measure the required width of the train, it is better to make it a little wider, and then carefully trim it to the desired width. Everything must be done carefully, especially the edges of the train. Now we put it in place.

We check the operation of the drive. So that the loop does not cling to anything.

Assemble the DVD player in reverse order. We put the drive, board, cable and connectors in their places, close the case, and enjoy watching your favorite movies

Good luck with the repair! Come to our Forum.

According to the proposed scheme below, you can assemble a simple temperature-to-frequency converter.

It operates over a temperature range of 0 to 100°F (-20°C to +40°C) and converts to a frequency between 0 and 1 kHz.

With years of experience with a variety of American Power Conversion UPS models operating in harsh rural power environments, the mouse shares tips you won't find in a technical manual or any other book. You will learn how to extend the life of the UPS or even resurrect the unit, while not being an electronics engineer and not having any measuring equipment at hand, except for a Chinese multimeter. Read more…

The utility model relates to materials science of textile and light industry products, namely to methods for studying the structure and properties of knitted fabrics during their laboratory and production tests.

Video (click to play).

The disadvantage of the prototypes of this device can be attributed to the fact that they are focused on solving only a narrow measurement problem, namely, determining the breathability of a knitted fabric, taking into account its actual density.

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