Disassemble the headlamp. How to fix an LED Chinese flashlight yourself. DIY instructions for repairing LED lights with visual photos and videos. How does an LED flashlight work?
As you can see, the scheme is simple. Main elements: current-limiting capacitor, rectifier diode bridge with four diodes, battery, switch, super-bright LEDs, LED to indicate flashlight battery charging.
Well, now, in order, about the purpose of all the elements in the flashlight.
Current limiting capacitor. It is designed to limit the battery charging current. Its capacity for each type of flashlight may be different. A non-polar mica capacitor is used. The operating voltage must be at least 250 volts. In the circuit it must be bypassed, as shown, with a resistor. It serves to discharge the capacitor after you remove the flashlight from the charging outlet. Otherwise, you may get an electric shock if you accidentally touch the 220 volt power terminals of the flashlight. The resistance of this resistor must be at least 500 kOhm.
The rectifier bridge is assembled on silicon diodes with a reverse voltage of at least 300 volts.
To indicate the charging of the flashlight battery, a simple red or green LED is used. It is connected in parallel to one of the diodes of the rectifier bridge. True, in the diagram I forgot to indicate the resistor connected in series with this LED.
It makes no sense to talk about the other elements; everything should be clear anyway.
I would like to draw your attention to the main points of repairing an LED flashlight. Let's look at the main faults and how to fix them.
1. The flashlight stopped shining. There aren't many options here. The reason may be the failure of super-bright LEDs. This can happen, for example, in the following case. You put the flashlight on charge and accidentally turned on the switch. In this case, a sharp jump in current will occur and one or more diodes of the rectifier bridge may be broken. And behind them, the capacitor may not be able to withstand it and will short out. The voltage on the battery will increase sharply and the LEDs will fail. So, under no circumstances turn on the flashlight while charging unless you want to throw it away.
2. The flashlight does not turn on. Well, here you need to check the switch.
3. The flashlight discharges very quickly. If your flashlight is “experienced”, then most likely the battery has reached its service life. If you actively use the flashlight, then after one year of use the battery will no longer last.
Problem 1: The LED flashlight does not turn on or flickers when working
As a rule, this is the cause of poor contact. The easiest way to treat it is to tighten all the threads tightly.
If the flashlight doesn't work at all, start by checking the battery. It may be discharged or damaged.
Unscrew the back cover of the flashlight and use a screwdriver to connect the housing to the negative terminal of the battery. If the flashlight lights up, then the problem is in the module with the button.
90% of the buttons of all LED lights are made according to the same scheme:
The button body is made of aluminum with a thread, a rubber cap is inserted there, then the button module itself and a pressure ring for contact with the body.
The problem is most often solved by a loose clamping ring.
To fix this problem, just find round pliers with thin tips or thin scissors that need to be inserted into the holes, as in the photo, and turned clockwise.
If the ring moves, the problem is fixed. If the ring stays in place, then the problem lies in the contact of the button module with the body. Unscrew the clamping ring counterclockwise and pull the button module out.
Poor contact often occurs due to oxidation of the aluminum surface of the ring or border on the printed circuit board (indicated by arrows)
Simply wipe these surfaces with alcohol and functionality will be restored.
Button modules are different. Some have contact through the printed circuit board, others have contact through the side petals to the flashlight body.
Just bend this petal to the side so that the contact is tighter.
Alternatively, you can make a solder from tin so that the surface is thicker and the contact is pressed better.
All LED lights are basically the same
The plus goes through the positive contact of the battery to the center of the LED module.
The negative goes through the body and is closed with a button.
It would be a good idea to check the tightness of the LED module inside the housing. This is also a common problem with LED lights.
Using round nose pliers or pliers, rotate the module clockwise until it stops. Be careful, it is easy to damage the LED at this point.
These actions should be quite enough to restore the functionality of the LED flashlight.
It’s worse when the flashlight works and the modes are switched, but the beam is very dim, or the flashlight doesn’t work at all and there’s a burning smell inside.
Problem 2. The flashlight works fine, but is dim or does not work at all and there is a burning smell inside
Most likely the driver has failed.
The driver is an electronic circuit on transistors that controls the flashlight modes and is also responsible for a constant voltage level, regardless of battery discharge.
You need to unsolder the burnt driver and solder in a new driver, or connect the LED directly to the battery. In this case, you lose all modes and are left only with the maximum one.
Sometimes (much less often) the LED fails.
You can check this very simply. Apply a voltage of 4.2 V/ to the contact pads of the LED. The main thing is not to confuse the polarity. If the LED lights up brightly, then the driver has failed, if vice versa, then you need to order a new LED.
Unscrew the module with the LED from the housing.
Modules vary, but as a rule, they are made of copper or brass and
The weakest point of such flashlights is the button. Its contacts oxidize, as a result of which the flashlight begins to shine dimly, and then may stop turning on altogether.
The first sign is that a flashlight with a normal battery shines dimly, but if you click the button several times, the brightness increases.
The easiest way to make such a lantern shine is to do the following:
1. Take a thin stranded wire and cut off one strand.
2. We wind the wires onto the spring.
3. We bend the wire so that the battery does not break it. The wire should protrude slightly
above the twisting part of the flashlight.
4. Twist tightly. We break off (tear off) the excess wire.
As a result, the wire provides good contact with the negative part of the battery and the flashlight
will shine with proper brightness. Of course, the button is no longer available for such repairs, so
Turning on and off the flashlight is done by turning the head part.
My Chinese guy worked like this for a couple of months. If you need to change the battery, the back of the flashlight
should not be touched. We turn our heads away.
RESTORING THE OPERATION OF THE BUTTON.
Today I decided to bring the button back to life. The button is located in a plastic case, which
It's just pressed into the back of the light. In principle, it can be pushed back, but I did it a little differently:
1. Use a 2 mm drill to make a couple of holes to a depth of 2-3 mm.
2. Now you can use tweezers to unscrew the housing with the button.
3. Remove the button.
4. The button is assembled without glue or latches, so it can be easily disassembled with a stationery knife.
The photo shows that the moving contact has oxidized (a round thing in the center that looks like a button).
You can clean it with an eraser or fine sandpaper and put the button back together, but I decided to additionally tin both this part and the fixed contacts.
1. Clean with fine sandpaper.
2. Apply a thin layer to the areas marked in red. We wipe off the flux with alcohol,
assembling the button.
3. To increase reliability, I soldered a spring to the bottom contact of the button.
4. Putting everything back together.
After repair, the button works perfectly. Of course, tin also oxidizes, but since tin is a fairly soft metal, I hope that the oxide film will be
easy to break down. It’s not for nothing that the central contact on light bulbs is made of tin.
IMPROVING FOCUS.
My Chinese had a very vague idea of what a “hotspot” was, so I decided to enlighten him.
Unscrew the head part.
1. There is a small hole in the board (arrow). Use an awl to twist out the filling.
At the same time, lightly press your finger on the glass from the outside. This makes it easier to unscrew.
2. Remove the reflector.
3. Take ordinary office paper and punch 6-8 holes with an office hole punch.
The diameter of the holes in the hole punch matches perfectly with the diameter of the LED.
Cut out 6-8 paper washers.
4. Place the washers on the LED and press it with the reflector.
Here you will have to experiment with the number of washers. I improved the focusing of a couple of flashlights in this way; the number of washers was in the range of 4-6. The current patient required 6 of them.
INCREASE THE BRIGHTNESS (for those who know a little about electronics).
The Chinese save on everything. A couple of extra details will increase the cost, so they don’t install it.
The main part of the diagram (marked in green) may be different. On one or two transistors or on a specialized microcircuit (I have a circuit of two parts:
inductor and a 3-leg IC similar to a transistor). But they save on the part marked in red. I added a capacitor and a pair of 1n4148 diodes in parallel (I didn't have any shots). The brightness of the LED increased by 10-15 percent.
1. This is what the LED looks like in similar Chinese ones. From the side you can see that there are thick and thin legs inside. The thin leg is a plus. You need to be guided by this sign, because the colors of the wires can be completely unpredictable.
2. This is what the board looks like with the LED soldered to it (on the back side). Green color indicates foil. The wires coming from the driver are soldered to the legs of the LED.
3. Using a sharp knife or a triangular file, cut the foil on the positive side of the LED.
We sand the entire board to remove the varnish.
4. Solder the diodes and capacitor. I took the diodes from a broken computer power supply, and soldered the tantalum capacitor from some burnt-out hard drive.
The positive wire now needs to be soldered to the pad with the diodes.
As a result, the flashlight produces (by eye) 10-12 lumens (see photo with hotspots),
judging by the Phoenix, which produces 9 lumens in minimum mode.
Hi all! Reviews on Mysku of this either a flashlight or a shocker encouraged me to buy it as a dog repeller. The device came to me partially working: the flashlight was shining, the shocker was sparking, but the battery was not charging from the mains. Therefore, the lantern was disassembled, as a result I myself was somewhat shocked by its internal contents, although I assumed that I would see something similar. My review is an addition to existing reviews, that is, a description of the internal structure of this flashlight-shocker.
I bought the flashlight after the review, this was my second order from TinyDeal. The order arrived to me after about 50 days, in a “simple” (as the postal workers put it) parcel without any registration - postal notices are not sent even to the addressees for such parcels. This was the first time I received such a parcel.
I brought it home, unpacked it, examined it, checked it. The flashlight works, the shocker sparks quite loudly, which is what I needed. Among the defects, I immediately noticed a crack on the plastic glass covering the flashlight, and in general the glass itself was somewhat cloudy. I shook the lantern - nothing seemed to be loose inside it.
I involuntarily tested the shock on myself when I pressed the “start” button once without making sure that the “shocking” was turned off. It so happened that I was holding the lantern by the body, and my hand slightly touched the “crown” of the lantern. The electric shock was quite strong, without a spark discharge, and it pierced the plastic of the crown, since I did not touch the contact plates. I have been repeatedly shocked by voltage sources ranging from 110 volts to 30 kV (the scars still remain), and in general I am not very sensitive to this, since the skin on my fingers is quite rough. I assess the “shocking” effect of the flashlight as quite strong, approximately equal to an electric shock from a 220-volt network. 380 volts struck me only once, and this was perhaps the most dangerous case. The kilovolts in this shocker are purely for the visible effect, and to pierce clothes. If the goal is to shock rather than spark, then a voltage of 500 volts would be sufficient, given that the current would increase significantly. Well, the place where the current is applied is very important.
After playing with the flashlight a little, I didn’t bring it to the point where the battery was completely drained, but I still decided to charge it: it was interesting what happens when you plug the flashlight into the mains for charging. It turned out - nothing! Nothing at all! The LED at the end of the flashlight handle did not light up, and by all indications, charging was not taking place. Okay, I checked the cord (who thought of making the cord so short?!) - the cord is fine. So why isn't it charging? I clicked the switches - the result was zero. The review says that charging from the mains occurs only when the switch at the end of the handle is in the “On” position, but in my case nothing changed.
Without much hesitation, I unscrew the two screws securing the plastic back of the flashlight to the metal one. With a little effort, I remove this plastic part from the lantern. And there…
I took photographs after I had disassembled everything, so some of the photos appear to be “advanced.”
I haven’t seen such a collective farm for a long time... the wires from the terminals for connecting the charging cord are soldered to the capacitor and the rectifier assembly hanging on the terminals of the capacitor. The wires from the output of the rectifier assembly go deep into the device.
The capacitor even had its casing material crumble due to excessive bending of the lead.
And the main thing is that all this is not insulated by anything, not even just a roll of electrical tape over the conductor with the rectifier. If you consider that the wires are thin and the quality of the insulation does not suffer, then you can quite expect a short circuit and fireworks. There is no fuse. A short circuit inside the flashlight can also be caused by self-tapping screws sticking out inside the flashlight that secure the back cover. It’s good that at least the connections of the wires to the high-voltage converter are insulated, I should have checked what was there, soldering or twisting, but I forgot to do this.
Next, we look more closely inside the back cover and find that the charge indication LED is soldered through a resistor to the terminals, that is, it should light up immediately when external power is applied, and stay on all the time while the flashlight is connected to the network. The review says that the LED goes out when the battery is charged - is there really a charge controller in that lantern? I doubt something, maybe there is an inaccuracy in the review? Well, it is clear that the switch does not need to be switched to “On” for charging; it is connected to the high-voltage generator circuit, and not to charging the battery.
But why doesn't the LED light up when external power is applied? It is unlikely that it has been faulty like this since new. Ah... Here's the thing... The LED, along with the wire going to the rectifier, just stupidly fell off the terminal: bad soldering. Well, now it’s clear why there is no charge and the LED doesn’t light up. I'll solder it.
But since I partially disassembled the lantern, I couldn’t stop there. Moreover, I already saw the end of a plastic cylinder, inside of which two wires went. I guessed that this is a 400KV high voltage generator, as its description on Aliexpress says (review). But if there is a voltage converter here, then where is the battery? I pulled the voltage converter towards me - it didn’t really resist, and I decided that the high-voltage wires were long enough that I could remove the converter. And indeed, I took it out, but only together with the explosive wires, which turned out to be very short, and which I, it turns out, tore out of the “crown” of the flashlight. This was a surprise, because I thought that the explosive wires were soldered to the contacts, but it turns out that soldering is an unaffordable luxury in this case (in Chinese).
Well, I tore it out and tore it out... It is impossible to put the explosive wires back without further disassembly, so I continue to gut the lantern. On the side of the handle you can see a plastic part - a button and switch holder, secured with a locking ring.
Just in case, I twisted the explosive wires, leaving a gap of about 1 cm between their ends - if I decide to check the operation of the explosive converter, it will not burn out due to excess voltage at the output, which would happen if the ends of the wires were separated in different directions. I couldn't stand it and checked the discharge disassembled - there is a discharge.
But how to remove the plastic “crown” from the lantern? I moved it and felt a slight play. At first I thought that the crown was glued, but it turned out that two screws were hidden under a black strip with an inscription glued to the edge of the metal part of the lantern. I peeled off the strip, unscrewed the screws, removed the crown, and after it a plastic “bucket” with an LED fell out onto the table, as well as a very remarkable battery.
At first, looking at the battery, I was very surprised: was it really produced in 2010? But among the bourgeoisie, the first digit is usually the year of manufacture, and it turns out that the battery is from 2013. Since the flashlight arrived charged, then perhaps the battery is not so bad, at least in terms of self-discharge. Its type and capacity from the marking “FEIYU 3.6v 1” are unclear, but it is 100% nickel-cadmium, and I measured approximately 3.8V for three of its series-connected cans. Approximately what capacity can it be? To prevent the battery from dangling, it was pressed with a fabric pad (visible in the photo). There is no insulation, not even one layer of electrical tape.
Also, there is no insulation for the super-duper LED driver - a resistor, and a moving resistor could easily short-circuit the battery. But the fact that the resistor is present, as I understand it, is already good; sometimes they don’t even put a shortcut. I wrapped some electrical tape around the rezuk.
I understood the reason for the crack in the glass of the lantern: it was a self-tapping screw embedded in the side surface of the transparent “cup”. The reason is the crooked installation of the “piece of glass” - if it is placed evenly, the self-tapping screw only slightly touches its end, and does not lead to the appearance of cracks.
I began to put the lantern back together. During disassembly, I completely in vain removed the “snapper” (slider) from the flashlight mode switch, and the plastic sleeve with the switch and the shocker activation button turned inside the flashlight body.
At the same time, the top of the button popped out, and it took some effort for me to return it to its place, turn the sleeve to the desired position and place the slider on the switch.
I must say that while fiddling with the disassembled flashlight, I was mentally prepared for the fact that the poorly soldered wires would fall off the switch or button, but nevertheless the soldering held up, even though I pulled the wires quite a bit in the process of examining the flashlight.
I stuffed the high-voltage generator back into the lantern housing and ran the wires to the crown. When screwing the back cover, the screws pass through the plastic of the high-voltage generator housing, preventing it from becoming loose. The wires are not connected to the aluminum contact inserts in the crown; the design simply provides a small distance between the explosive wires and the crown contacts. At the same time, it cannot be guaranteed whether there is electrical contact or not - it is a matter of chance. If there is contact now, then with strong vibration, impacts of the flashlight or falls, the wires can “run away” and an extra spark gap will appear. The high-voltage wires of my generator even had conductors slightly recessed into the insulation; therefore, in addition to the visible external discharge, small discharges also occurred inside the plastic crown, as evidenced by the burn marks left by the discharges on the aluminum inserts. To prevent the aluminum inserts from jumping out due to vibration, etc., it is advisable to secure them with glue.
To increase the likelihood of electrical contact between the explosive wires and the plates, I cut off the insulation so that approximately 0.3 mm of the central core of the wire protruded from it, inserted the wires into the holes in the crown, and put the crown in place. This operation had to be repeated, since when installing the crown a couple of times the wires slipped out of their destinations. There is no way to secure the wires better, since they are too short. It was possible to drop some glue, but I didn’t, you never know I’ll have to take it apart (almost certainly).
Well, that seems to be it... I've assembled the flashlight so far, everything works, it shines, it sparkles, but I haven't charged it yet, and the main question is how long does it take to charge this battery of unknown capacity. If anyone has worked with this and knows its capacity, please tell me. I couldn't find any similar designations.
Even before opening the flashlight, I wrote on TinyDeal that the flashlight is faulty, is not charging, and attached a couple of photos in which the flashlight is plugged in, but the “charging” LED is not lit. The store's reaction was interesting. So, after some arguing with TinyDeal, I was offered a $7 refund in the form of TD points. Or, when ordering over $45, TD promised to send another such shocker flashlight for free, which is very strange: this flashlight has had the “sold out” status for a long time. Since I already had my eye on one flashlight at TD (just a flashlight, without a shocker), I agreed to return 7 bucks, especially since I don’t plan to buy anything large there in the near future.
Maybe someday, if I get around to it, I’ll remake this flashlight for a lithium battery with a USB charging controller and a normal LED driver, and maybe with a different LED. True, in order to install a more powerful LED, you will need to grind out the heat sink adapter to replace the original plastic holder. The main question is what lithium-ion battery or battery will fit here, what format? Certainly not 18650, so perhaps installing a more powerful LED does not make sense.
Perhaps the first modification of the flashlight will be to convert it to charge the battery using a voltage of 5V from USB, you just need to install a resistor, maybe even plug a mini-USB connector into the flashlight. The charging time will be significantly reduced, although you will need to control this time yourself, but most importantly, the likelihood of fireworks when charging from the network will decrease. I haven't done it yet.
I'm planning to buy +9 Add to favorites I liked the review +24 +58
As you can see, the scheme is simple. Main elements: current-limiting capacitor, rectifier diode bridge with four diodes, battery, switch, super-bright LEDs, LED to indicate flashlight battery charging.
Well, now, in order, about the purpose of all the elements in the flashlight.
Current limiting capacitor. It is designed to limit the battery charging current. Its capacity for each type of flashlight may be different. A non-polar mica capacitor is used. The operating voltage must be at least 250 volts. In the circuit it must be bypassed, as shown, with a resistor. It serves to discharge the capacitor after you remove the flashlight from the charging outlet. Otherwise, you may get an electric shock if you accidentally touch the 220 volt power terminals of the flashlight. The resistance of this resistor must be at least 500 kOhm.
The rectifier bridge is assembled on silicon diodes with a reverse voltage of at least 300 volts.
To indicate the charging of the flashlight battery, a simple red or green LED is used. It is connected in parallel to one of the diodes of the rectifier bridge. True, in the diagram I forgot to indicate the resistor connected in series with this LED.
It makes no sense to talk about the other elements; everything should be clear anyway.
I would like to draw your attention to the main points of repairing an LED flashlight. Let's look at the main faults and how to fix them.
1. The flashlight stopped shining. There aren't many options here. The reason may be the failure of super-bright LEDs. This can happen, for example, in the following case. You put the flashlight on charge and accidentally turned on the switch. In this case, a sharp jump in current will occur and one or more diodes of the rectifier bridge may be broken. And behind them, the capacitor may not be able to withstand it and will short out. The voltage on the battery will increase sharply and the LEDs will fail. So, under no circumstances turn on the flashlight while charging unless you want to throw it away.
2. The flashlight does not turn on. Well, here you need to check the switch.
3. The flashlight discharges very quickly. If your flashlight is “experienced”, then most likely the battery has reached its service life. If you actively use the flashlight, then after one year of use the battery will no longer last.
Problem 1: The LED flashlight does not turn on or flickers when working
As a rule, this is the cause of poor contact. The easiest way to treat it is to tighten all the threads tightly.
If the flashlight doesn't work at all, start by checking the battery. It may be discharged or damaged.
Unscrew the back cover of the flashlight and use a screwdriver to connect the housing to the negative terminal of the battery. If the flashlight lights up, then the problem is in the module with the button.
90% of the buttons of all LED lights are made according to the same scheme:
The button body is made of aluminum with a thread, a rubber cap is inserted there, then the button module itself and a pressure ring for contact with the body.
The problem is most often solved by a loose clamping ring.
To fix this problem, just find round pliers with thin tips or thin scissors that need to be inserted into the holes, as in the photo, and turned clockwise.
If the ring moves, the problem is fixed. If the ring stays in place, then the problem lies in the contact of the button module with the body. Unscrew the clamping ring counterclockwise and pull the button module out.
Poor contact often occurs due to oxidation of the aluminum surface of the ring or border on the printed circuit board (indicated by arrows)
Simply wipe these surfaces with alcohol and functionality will be restored.
Button modules are different. Some have contact through the printed circuit board, others have contact through the side petals to the flashlight body.
Just bend this petal to the side so that the contact is tighter.
Alternatively, you can make a solder from tin so that the surface is thicker and the contact is pressed better.
All LED lights are basically the same
The plus goes through the positive contact of the battery to the center of the LED module.
The negative goes through the body and is closed with a button.
It would be a good idea to check the tightness of the LED module inside the housing. This is also a common problem with LED lights.
Using round nose pliers or pliers, rotate the module clockwise until it stops. Be careful, it is easy to damage the LED at this point.
These actions should be quite enough to restore the functionality of the LED flashlight.
It’s worse when the flashlight works and the modes are switched, but the beam is very dim, or the flashlight doesn’t work at all and there’s a burning smell inside.
Problem 2. The flashlight works fine, but is dim or does not work at all and there is a burning smell inside
Most likely the driver has failed.
The driver is an electronic circuit on transistors that controls the flashlight modes and is also responsible for a constant voltage level, regardless of battery discharge.
You need to unsolder the burnt driver and solder in a new driver, or connect the LED directly to the battery. In this case, you lose all modes and are left only with the maximum one.
Sometimes (much less often) the LED fails.
You can check this very simply. Apply a voltage of 4.2 V/ to the contact pads of the LED. The main thing is not to confuse the polarity. If the LED lights up brightly, then the driver has failed, if vice versa, then you need to order a new LED.
Unscrew the module with the LED from the housing.
Modules vary, but as a rule, they are made of copper or brass and
The weakest point of such flashlights is the button. Its contacts oxidize, as a result of which the flashlight begins to shine dimly, and then may stop turning on altogether.
The first sign is that a flashlight with a normal battery shines dimly, but if you click the button several times, the brightness increases.
The easiest way to make such a lantern shine is to do the following:
1. Take a thin stranded wire and cut off one strand.
2. We wind the wires onto the spring.
3. We bend the wire so that the battery does not break it. The wire should protrude slightly
above the twisting part of the flashlight.
4. Twist tightly. We break off (tear off) the excess wire.
As a result, the wire provides good contact with the negative part of the battery and the flashlight
will shine with proper brightness. Of course, the button is no longer available for such repairs, so
Turning on and off the flashlight is done by turning the head part.
My Chinese guy worked like this for a couple of months. If you need to change the battery, the back of the flashlight
should not be touched. We turn our heads away.
RESTORING THE OPERATION OF THE BUTTON.
Today I decided to bring the button back to life. The button is located in a plastic case, which
It's just pressed into the back of the light. In principle, it can be pushed back, but I did it a little differently:
1. Use a 2 mm drill to make a couple of holes to a depth of 2-3 mm.
2. Now you can use tweezers to unscrew the housing with the button.
3. Remove the button.
4. The button is assembled without glue or latches, so it can be easily disassembled with a stationery knife.
The photo shows that the moving contact has oxidized (a round thing in the center that looks like a button).
You can clean it with an eraser or fine sandpaper and put the button back together, but I decided to additionally tin both this part and the fixed contacts.
1. Clean with fine sandpaper.
2. Apply a thin layer to the areas marked in red. We wipe off the flux with alcohol,
assembling the button.
3. To increase reliability, I soldered a spring to the bottom contact of the button.
4. Putting everything back together.
After repair, the button works perfectly. Of course, tin also oxidizes, but since tin is a fairly soft metal, I hope that the oxide film will be
easy to break down. It’s not for nothing that the central contact on light bulbs is made of tin.
IMPROVING FOCUS.
My Chinese had a very vague idea of what a “hotspot” was, so I decided to enlighten him.
Unscrew the head part.
1. There is a small hole in the board (arrow). Use an awl to twist out the filling.
At the same time, lightly press your finger on the glass from the outside. This makes it easier to unscrew.
2. Remove the reflector.
3. Take ordinary office paper and punch 6-8 holes with an office hole punch.
The diameter of the holes in the hole punch matches perfectly with the diameter of the LED.
Cut out 6-8 paper washers.
4. Place the washers on the LED and press it with the reflector.
Here you will have to experiment with the number of washers. I improved the focusing of a couple of flashlights in this way; the number of washers was in the range of 4-6. The current patient required 6 of them.
INCREASE THE BRIGHTNESS (for those who know a little about electronics).
The Chinese save on everything. A couple of extra details will increase the cost, so they don’t install it.
The main part of the diagram (marked in green) may be different. On one or two transistors or on a specialized microcircuit (I have a circuit of two parts:
inductor and a 3-leg IC similar to a transistor). But they save on the part marked in red. I added a capacitor and a pair of 1n4148 diodes in parallel (I didn't have any shots). The brightness of the LED increased by 10-15 percent.
1. This is what the LED looks like in similar Chinese ones. From the side you can see that there are thick and thin legs inside. The thin leg is a plus. You need to be guided by this sign, because the colors of the wires can be completely unpredictable.
2. This is what the board looks like with the LED soldered to it (on the back side). Green color indicates foil. The wires coming from the driver are soldered to the legs of the LED.
3. Using a sharp knife or a triangular file, cut the foil on the positive side of the LED.
We sand the entire board to remove the varnish.
4. Solder the diodes and capacitor. I took the diodes from a broken computer power supply, and soldered the tantalum capacitor from some burnt-out hard drive.
The positive wire now needs to be soldered to the pad with the diodes.
As a result, the flashlight produces (by eye) 10-12 lumens (see photo with hotspots),
judging by the Phoenix, which produces 9 lumens in minimum mode.
No, miracles still don’t happen... A good flashlight cannot be bought cheaply. This is an axiom. But it is not reversible. A high price is also not a guarantee of quality.
Well, the lyrical digression is over, now about flashlights.
The flashlight I want to talk about now probably holds the record for participation in reviews. This is one of the most common models in Chinese stores. COVEX lens, CREE diode, many lumens, cheap and with a fairly nice design. These flashlights are bought by almost everyone who chooses an inexpensive flashlight.
I was no exception. This flashlight was my first zoom flashlight with a Covex lens.
Everything on the seller’s website was very beautiful: a lot of photos, descriptions, gifts for simpletons who suddenly buy lots and lots of this shit..., photographs of production and many, many certificates (ha ha). Looking ahead, I will say that the flashlight, of course, is a basement-knee assembly made from unknown materials and everything on this seller’s page is a deception.
The facade of some kind of production.
Here is a photo supposedly from the production of flashlights. I don’t know where the seller misrepresented this photo...
Unreadable certificates. Of course, not for this product and not for this production.
This is how this flashlight shines:
Actually, that’s how the flashlight was shining. This is with the lens fully extended. When pulled in, the result was an even circle of light with a clear boundary. This is why I love zoomable flashlights. Here the seller did not deceive, but this is not his merit, this is a COVEX lens.
Externally everything is beautiful, there is nothing to complain about. The flashlight came with a cartridge for three AAA batteries. The diode inside was, of course, not CREE, but some kind of incomprehensible one that looked like an ordinary EPISTAR, but with a square luminous surface. It shone well, brightly (looking ahead, I’ll say that it didn’t last long), so I planted AAA elements with incredible gluttony. At the same time, the flashlight did not heat up at all.
Now I have already gained experience, but at that moment I did not understand what was wrong with the flashlight. I just had the original extension ring for this flashlight, which allows me to put a Li-Ion 18650 battery in it. The battery fit like original, the flashlight shone brightly and beautifully, but for some reason it became dimmer and dimmer until it barely began to shine at all. then blue light. Having examined the diode, I saw that it had turned black, obviously due to overheating. I took the flashlight apart. This is where everything fell into place.
Here is an almost complete dismemberment, I did not remove only the sealing rings.
There are no complaints about the case. The aluminum is clearly factory made, quite decent. Let's put it aside.
Yes Yes. Only a super-greedy sadistic pervert could have thought of this. Sharpening this aluminum module is, of course, a few cents more expensive. And no one cares about the fact that the LED will burn out very quickly from overheating. That is, whoever came up with the idea to do this knew in advance that the reliability of this product would be zero and the buyer would not be able to use it.
Oh, there's a spring in the back. Strange, they could have saved a tenth of a cent here too.
What about the driver? Naturally... no.
There is one detail in the driver - wiring. But what reliability. It won't burn. What an elegant, laconic product.
Some number has been etched. A! that's why there is a spring there, this ready-made factory product was purchased ready-made, already with a spring.
And here is the incomprehensible “left” LED. Already burned, poor thing...
This is the culprit detail. Even if it were the same shape but made of aluminum, it would still be bad. It's irregularly shaped.
Let's talk about the shape: it has a hole inside and the LED board rests on a small threshold; the contact area of the aluminum LED board and this ring is very small. And through this ring the heat should be transferred to the body. There should be a flat area under the LED board with a maximum contact area. With zoomable flashlights, heat dissipation is already a big problem; not only would there be minimal thermal contact, but with the plastic part there was no heat dissipation at all. This plastic part must not be used.
Let's admire the light-and-light pattern one last time... and then throw it in the trash.
What's next? Make a new ring (heat sink module) and buy an LED and driver? This could be a solution to the problem if I had a lathe or a good lathe friend. I won’t simply order a turner from the factory, considering the prices they charge. It will be cheaper to buy another flashlight. The option is no longer available.
Throw away this junk and buy another flashlight from a more honest seller? And where is the guarantee that after two months of waiting the same $#%45%, or even worse, will not arrive? At least the case here is of high quality.
The third option is to buy the correct module with driver and LED assembly. This is the option I chose. .
Here's what it looks like:
Diode CREE XM-L T6
Normal driver. There is a spring.
In the module under the LED board there is not a hole, but a contact pad lubricated with thermal conductive paste.
All that remains is to lightly lubricate the threads with thermal paste and screw on the purchased module instead of the misunderstanding that was in the flashlight initially.
Now it’s really not scary to turn on the flashlight... at least you can hope that it won’t burn out in a few minutes.
Do not under any circumstances buy anything there! There is a complete deception there.
You might be interested:
CREE XM-L module (single-mode driver) for replacement in C8, T6 flashlight
Many people have various Chinese lanterns that run on a single battery. Something like this:
Unfortunately, they are very short-lived. I will tell you further about how to bring a flashlight back to life and about some simple modifications that can improve such flashlights.
The weakest point of such flashlights is the button. Its contacts oxidize, as a result of which the flashlight begins to shine dimly, and then may stop turning on altogether.
The first sign is that a flashlight with a normal battery shines dimly, but if you click the button several times, the brightness increases.
The easiest way to make such a lantern shine is to do the following: 
1. Take a thin stranded wire and cut off one strand.
2. We wind the wires onto the spring.
3. We bend the wire so that the battery does not break it. The wire should protrude slightly
above the twisting part of the flashlight.
4. Twist tightly. We break off (tear off) the excess wire.
As a result, the wire provides good contact with the negative part of the battery and the flashlight
will shine with proper brightness. Of course, the button is no longer available for such repairs, so
Turning the flashlight on and off is done by turning the head part.
My Chinese guy worked like this for a couple of months. If you need to change the battery, the back of the flashlight
should not be touched. We turn our heads away.
RESTORING THE OPERATION OF THE BUTTON.
Today I decided to bring the button back to life. The button is located in a plastic case, which
It's just pressed into the back of the light. In principle, it can be pushed back, but I did it a little differently: 
1. Use a 2 mm drill to make a couple of holes to a depth of 2-3 mm.
2. Now you can use tweezers to unscrew the housing with the button.
3. Remove the button.
4. The button is assembled without glue or latches, so it can be easily disassembled with a stationery knife.
The photo shows that the moving contact has oxidized (a round thing in the center that looks like a button).
You can clean it with an eraser or fine sandpaper and put the button back together, but I decided to additionally tin both this part and the fixed contacts. 
1. Clean with fine sandpaper.
2. Apply a thin layer to the areas marked in red. We wipe off the flux with alcohol,
assembling the button.
3. To increase reliability, I soldered a spring to the bottom contact of the button.
4. Putting everything back together.
After repair, the button works perfectly. Of course, tin also oxidizes, but since tin is a fairly soft metal, I hope that the oxide film will be
easy to break down. It’s not for nothing that the central contact on light bulbs is made of tin.
IMPROVING FOCUS.
My Chinese had a very vague idea of what a “hotspot” was, so I decided to enlighten him.
Unscrew the head part. 
1. There is a small hole in the board (arrow). Use an awl to twist out the filling.
At the same time, lightly press your finger on the glass from the outside. This makes it easier to unscrew.
2. Remove the reflector.
3. Take ordinary office paper and punch 6-8 holes with an office hole punch.
The diameter of the holes in the hole punch matches perfectly with the diameter of the LED.
Cut out 6-8 paper washers.
4. Place the washers on the LED and press it with the reflector.
Here you will have to experiment with the number of washers. I improved the focusing of a couple of flashlights in this way; the number of washers was in the range of 4-6. The current patient required 6 of them.
What happened in the end: 
On the left is our Chinese, on the right is Fenix LD 10 (at minimum).
The result is quite pleasant. The hotspot became pronounced and uniform.
INCREASE THE BRIGHTNESS (for those who know a little about electronics).
The Chinese save on everything. A couple of extra details will increase the cost, so they don’t install it. 
The main part of the diagram (marked in green) may be different. On one or two transistors or on a specialized microcircuit (I have a circuit of two parts:
inductor and a 3-leg IC similar to a transistor). But they save money on the part marked in red. I added a capacitor and a pair of 1n4148 diodes in parallel (I didn't have any shots). The brightness of the LED increased by 10-15 percent.
1. This is what the LED looks like in similar Chinese ones. From the side you can see that there are thick and thin legs inside. The thin leg is a plus. You need to be guided by this sign, because the colors of the wires can be completely unpredictable.
2. This is what the board looks like with the LED soldered to it (on the back side). Green color indicates foil. The wires coming from the driver are soldered to the legs of the LED.
3. Using a sharp knife or a triangular file, cut the foil on the positive side of the LED.
We sand the entire board to remove the varnish.
4. Solder the diodes and capacitor. I took the diodes from a broken computer power supply, and soldered the tantalum capacitor from some burnt-out hard drive.
The positive wire now needs to be soldered to the pad with the diodes.
As a result, the flashlight produces (by eye) 10-12 lumens (see photo with hotspots),
judging by the Phoenix, which produces 9 lumens in minimum mode.
And the last thing: the advantage of the Chinese over the branded flashlight (yes, don’t laugh)
Branded flashlights are designed to use batteries, so
With the battery discharged to 1 volt, my Fenix LD 10 simply does not turn on. At all.
I took a dead alkaline battery that had expired in the computer mouse. The multimeter showed that it had dropped to 1.12v. The mouse no longer worked on it, Fenix, as I said, did not start. But the Chinese one works! 
On the left is the Chinese, on the right is the Fenix LD 10 at minimum (9 lumens). Unfortunately, the white balance is off.
The phoenix has a temperature of 4200K. The Chinese is blue, but not as bad as in the photo.
Just for fun, I tried to finish off the battery. At this brightness level (5-6 lumens by eye), the flashlight worked for about 3 hours. The brightness is quite enough to illuminate your feet in a dark entrance/forest/basement. Then for another 2 hours the brightness decreased to the “firefly” level. Agree, 3-4 hours with acceptable light can solve a lot.
For this, let me take my leave.
Stari4ok.
Z.Y. The article is not a copy-paste. Made in I, especially for “NOT LOSS”!
