How to disassemble a Chinese lantern. 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?
Nowadays, the POLICE series flashlights are very popular, which can be purchased both on the market and by ordering on the Internet. In addition to a good flashlight, this device has a stun gun function.
Producing a fairly loud crack and a visible discharge of electricity, it effectively causes even large dogs to run away.
Although the device looks quite high quality, over time it stops working due to falls or rapid battery drain. In such cases, you want to do something to return the lantern to its former life.
And sometimes this can be done, the question remains, how to disassemble this device to get to its insides? From the outside it seems quite difficult, since the body looks cast and impregnable.
This article will describe how to disassemble one of these lights and possibly find the cause of the breakdown.
Since the flashlights are structurally almost identical, the disassembly method is also suitable for other models in this series.
You should start by removing the protective tape for the mounting screws. The photo shows how to do this.
It happens that this film falls off on its own over time.
So, using a suitable screwdriver, unscrew all the mounting screws, both in the front and in the back. Usually there are only four of them.
Next, pull the back part until it is removed.
There you will see wires going inside the device, charger elements and a piece of foam for greater density.
Everything is hinged and rather flimsy. So be extremely careful not to tear anything off and make things worse.
Here is a diode bridge, a damping capacitor and soldered connections, not insulated.
Now let's remove the front part. We pull it to the side in the same way - as with the back part - and it comes out easily.
Two wires are pulled out of it - these are high-voltage conductors, through which electric current flows to the front spark gaps.
Strange, but they are not even soldered, but simply inserted into the holes opposite the electrodes. Apparently, even without direct contact, the voltage penetrates the required distance to form an arc.
Otherwise, the front part is essentially a regular reflector. When it is put in place, the LED falls exactly in the center, appearing as if inside the reflector.
Let's move on to the back again. We extend the bridge with the capacitor as much as possible and take out the high-voltage coil embedded in the compound from the inside.
When you pull this coil, two high-voltage wires go from the back side into the flashlight. They need to be aligned, then this procedure will be easier.
As you can see in the photo, these conductors are simply inserted into the internal holes of the housing from the coil to the front electrodes.
This is how the removed high-voltage coil will look.
When assembling the wires, a thin copper wire tied to them will help you push the wires back through. You will need to tighten both ends at the same time.
We've dealt with the back part, let's move on to the front again.
We pull out the panel with the LED and behind it we find a battery pack assembled into one structure.
They are similar to micro finger ones, but have a slightly shorter length.
There are five of them in total and they are connected by metal plates, as if welded to their terminals.
This entire unit is placed in a polyethylene casing.
There are some inscriptions on it. Namely the voltage, which is six volts, and the date of manufacture. It turns out that each element has 1.2 volts, like a regular AA battery.
From this we can conclude that if you want to replace the battery, you can choose something. The main thing is to get it inside the flashlight body.
From the battery to the LED, the voltage goes through a resistance having a nominal value of about 15 ohms.
This photo shows the internal space where the battery should fit.
There is not much space, but you can pick something up.
Reassemble the lantern in reverse order. Considering the extremely unreliable assembly, everything must be done carefully so as not to tear off the wires and avoid short circuits between them and to the housing.
After working for about a year, my LED Headlight XM-L T6 headlamp began to turn on every once in a while, or even turn off without a command. Soon it stopped turning on completely.
The first thing I thought was that the battery in the battery compartment was failing.
To illuminate the rear LED HEADLIGHT indicator, a regular red SMD LED is used. Marked on the board as LED. It illuminates a plate of white plastic.
Since the battery compartment is located on the back of the head, this indicator is clearly visible at night.
Obviously it won’t hurt when cycling and walking along road routes.
Through a 100 Ohm resistor, the positive terminal of the red SMD LED is connected to the drain of the FDS9435A MOSFET transistor. Thus, when the flashlight is turned on, voltage is supplied to both the main Cree XM-L T6 XLamp LED and the low-power red SMD LED.
We've sorted out the main details. Now I'll tell you what's broken.
When you pressed the flashlight's power button, you could see that the red SMD LED began to shine, but very dimly. The operation of the LED corresponded to the standard operating modes of the flashlight (maximum brightness, low brightness and strobe). It became clear that the control chip U1 (FM2819) is most likely working.
Since it responds normally to pressing a button, then perhaps the problem lies in the load itself - a powerful white LED. Having unsoldered the wires going to the Cree XM-L T6 LED and connected it to a homemade power supply, I was convinced that it was working.
During measurements, it turned out that in maximum brightness mode, the drain of the FDS9435A transistor is only 1.2V. Naturally, this voltage was not enough to power the powerful Cree XM-L T6 LED, but it was enough for the red SMD LED to make its crystal glow dimly.
It became clear that the FDS9435A transistor, which is used in the circuit as an electronic key, is faulty.
I didn’t choose anything to replace the transistor, but bought an original P-channel PowerTrench MOSFET FDS9435A from Fairchild. Here is his appearance.
As you can see, this transistor has full markings and the distinctive sign of the Fairchild company ( F ), which released this transistor.
Having compared the original transistor with the one installed on the board, the thought crept into my head that a fake or less powerful transistor was installed in the flashlight. Perhaps even marriage. Still, the lantern did not even last a year, and the power element had already “thrown its hooves away.”
The pinout of the FDS9435A transistor is as follows.
As you can see, there is only one transistor inside the SO-8 case. Pins 5, 6, 7, 8 are combined and are the drain pin ( D rain). Pins 1, 2, 3 are also connected together and are the source ( S ource). The 4th pin is the gate ( G ate). It is to this that the signal comes from the control chip FM2819 (U1).
As a replacement for the FDS9435A transistor, you can use APM9435, AO9435, SI9435. These are all analogues.
You can desolder the transistor using either conventional methods or more exotic ones, for example, using Rose alloy. You can also use the brute force method - cut the leads with a knife, dismantle the case, and then unsolder the remaining leads on the board.
After replacing the FDS9435A transistor, the headlamp began to work properly.
This concludes the story about the renovation. But if I weren’t a curious radio mechanic, I would have left everything as it is. It works fine. But some moments haunted me.
Since initially I did not know that the microcircuit marked 819L (24) is FM2819, armed with an oscilloscope, I decided to see what signal the microcircuit supplies to the transistor gate under different operating modes. It's interesting.
When the first mode is turned on, -3.4...3.8V is supplied to the gate of the FDS9435A transistor from the FM2819 chip, which practically corresponds to the voltage on the battery (3.75...3.8V). Naturally, a negative voltage is applied to the gate of the transistor, since it is P-channel.
In this case, the transistor opens completely and the voltage on the Cree XM-L T6 LED reaches 3.4...3.5V.
In the minimum glow mode (1/4 brightness), about 0.97V comes to the FDS9435A transistor from the U1 chip. This is if you take measurements with a regular multimeter without any bells and whistles.
In fact, in this mode, a PWM (pulse width modulation) signal arrives at the transistor. Having connected the oscilloscope probes between the “+” power supply and the gate terminal of the FDS9435A transistor, I saw this picture.
Picture of a PWM signal on the oscilloscope screen (time/division - 0.5; V/division - 0.5). Sweep time is mS (milliseconds).
Since a negative voltage is applied to the gate, the “picture” on the oscilloscope screen is flipped. That is, now the photo in the center of the screen shows not an impulse, but a pause between them!
The pause itself lasts about 2.25 milliseconds (mS) (4.5 divisions of 0.5 mS). At this moment the transistor is closed.
Then the transistor opens for 0.75 mS. At the same time, voltage is supplied to the XM-L T6 LED. The amplitude of each pulse is 3V. And, as we remember, I measured only 0.97V with a multimeter. This is not surprising, since I measured constant voltage with a multimeter.
This is the moment on the oscilloscope screen. The time/division switch was set to 0.1 to better determine the pulse duration. The transistor is open. Don't forget that the shutter is marked with a minus "-". The impulse is reversed.
S = (2.25mS + 0.75mS) / 0.75mS = 3mS / 0.75mS = 4. Where,
S - duty cycle (dimensionless value);
Τ - repetition period (milliseconds, mS). In our case, the period is equal to the sum of switching on (0.75 mS) and pause (2.25 mS);
τ - pulse duration (milliseconds, mS). For us it is 0.75mS.
You can also define duty cycle(D), which in the English-speaking environment is called Duty Cycle (often found in all sorts of datasheets for electronic components). It is usually indicated as a percentage.
D = τ/Τ = 0.75/3 = 0.25 (25%). Thus, in low-brightness mode, the LED is turned on for only a quarter of the period.
When I did the calculations for the first time, my fill factor came out to 75%. But then, when I saw a line in the datasheet on the FM2819 about the 1/4 brightness mode, I realized that I had screwed up somewhere. I simply mixed up the pause and pulse duration, because out of habit I mistook the minus “-” on the shutter for the plus “+”. That's why it turned out the other way around.
In the "STROBE" mode, I was not able to view the PWM signal, since the oscilloscope is analog and quite old. I was unable to synchronize the signal on the screen and get a clear image of the pulses, although its presence was visible.
Typical connection diagram and pinout of the FM2819 microcircuit. Maybe someone will find it useful.
Some issues related to the operation of the LED also haunted me. I had somehow never dealt with LED lights before, but now I wanted to figure it out.
When I looked through the datasheet for the Cree XM-L T6 LED, which is installed in the flashlight, I realized that the value of the current-limiting resistor was too small (0.13 Ohm). Yes, and on the board one slot for a resistor was free.
When I was surfing the Internet in search of information about the FM2819 microcircuit, I saw photos of several printed circuit boards of similar flashlights. Some had four 1 Ohm resistors soldered to them, and some even had an SMD resistor marked “0” (jumper), which, in my opinion, is generally a crime.
An LED is a nonlinear element, and therefore a current-limiting resistor must be connected in series with it.
If you look at the datasheet for the Cree XLamp XM-L series LEDs, you will find that their maximum supply voltage is 3.5V, and the nominal voltage is 2.9V. In this case, the current through the LED can reach 3A. Here is the graph from the datasheet.
The rated current for such LEDs is considered to be a current of 700 mA at a voltage of 2.9V.
Specifically, in my flashlight, the current through the LED was 1.2 A at a voltage of 3.4...3.5V, which is clearly too much.
To reduce the forward current through the LED, instead of the previous resistors, I soldered four new ones with a nominal value of 2.4 Ohms (size 1206). I got a total resistance of 0.6 Ohm (power dissipation 0.125W * 4 = 0.5W).
After replacing the resistors, the forward current through the LED was 800 mA at a voltage of 3.15V. This way the LED will operate under a milder thermal regime, and hopefully will last a long time.
Since resistors of size 1206 are designed for a power dissipation of 1/8W (0.125 W), and in maximum brightness mode, about 0.5 W of power is dissipated on four current-limiting resistors, it is desirable to remove excess heat from them.
To do this, I cleaned the green varnish from the copper area next to the resistors and soldered a drop of solder onto it. This technique is often used on printed circuit boards of consumer electronic equipment.
After finalizing the electronic filling of the flashlight, I coated the printed circuit board with PLASTIK-71 varnish (electrical insulating acrylic varnish) to protect it from condensation and moisture.
When calculating the current-limiting resistor, I encountered some subtleties. The voltage at the drain of the MOSFET transistor should be taken as the LED supply voltage. The fact is that on the open channel of the MOSFET transistor, part of the voltage is lost due to the channel resistance (R (ds)on).
The higher the current, the more voltage “settles” along the Source-Drain path of the transistor. For me, at a current of 1.2A it was 0.33V, and at 0.8A - 0.08V. Also, part of the voltage drops on the connecting wires that go from the battery terminals to the board (0.04V). It would seem such a trifle, but in total it adds up to 0.12V. Since under load the voltage on the Li-ion battery drops to 3.67...3.75V, then the drain on the MOSFET is already 3.55...3.63V.
Another 0.5...0.52V is extinguished by a circuit of four parallel resistors. As a result, the LED receives a voltage of around 3-odd volts.
At the time of writing this article, an updated version of the reviewed headlamp appeared on sale. It already has a built-in Li-ion battery charge/discharge control board, and also adds an optical sensor that allows you to turn on the flashlight with a palm gesture.
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 friend 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.
ZY The article is not a copy-paste. Made in I, especially for “NOT PROPAD”!
For normal human life in the dark, he always needed light. With the development of technology, lighting sources have improved, starting from the fire of torches and kerosene lamps, ending with battery-powered flashlights. A real revolution in the world of lighting technology was the creation of the LED, which immediately entered everyday life.
Modern LED lights are very economical, the light spreads very far and is very bright. A huge share of such lithium flashlights on the modern market are made in China; they are very cheap and affordable. It is because of the cheapness that various types of breakdowns often occur. In this article, we will look at the main problems of repairing LED lights and how to fix them yourself.
How does an LED flashlight work?
The classic design of flashlights is very simple (regardless of the type of housing, be it the Cosmos or DiK AN-005 models). An LED is connected to the battery, the circuit is broken by the shutdown button. Depending on the number of LEDs, the number of light elements themselves (for example, the main light on the front and an auxiliary one in the handle), a stronger battery (or several), a transformer, a resistance are added to the circuit, and a more functional switch is installed (Fo-DiK flashlights) .
Why do flashlights break?
Now we will omit the problems associated with improper operation of the Chinese lantern - “I dropped it in a bowl of water, turned it on and off, but for some reason it does not shine.” The cheapness of flashlights is achieved by simplifying the electrical circuits inside the device. This allows you to save on components (their quantity and quality). This is done so that people buy new ones more often, and simply throw away the old ones without even trying to fix them with their own hands.
Another point of savings is people working in production who do not have sufficient qualifications to perform such work. As a result, there are many small and large errors in the circuit itself, poor-quality soldering and assembly of components, which leads to constant repair of the lamps. In most cases, all problems can be solved by diagnosing them correctly, which is what we will do next.
Cause of flashlight failure
Most likely, when the switch is switched, the LEDs do not want to light up due to a malfunction in the electrical circuit. The most common of them:
- oxidation of battery or battery contacts;
- oxidation on the contacts to which the battery is connected;
- damage to the wires going both from the battery to the LED and back;
- faulty shutdown element;
- lack of power in the circuit;
- failure in the LEDs themselves.
Oxidation. Most often it occurs in already old lanterns, which are often used in various weather conditions. The deposit that appears on the metal interferes with normal contact, which is why the battery-powered flashlight may flicker or not turn on at all. If oxidation is observed on the battery or accumulator, then you need to think about replacement.
How to fix contacts? Light stains can be removed with your own hands using a cotton swab dipped in ethyl alcohol. When the contamination is very serious, even rust has spread to the body - using such a battery can be dangerous to health and life. In stores you can now find a sufficient number of new batteries and accumulators, even for old types of flashlights.
Take care of the environment - do not throw old batteries in the trash, you probably have recycling collection points in your city.
Oxidation also forms on the contacts in the flashlight itself. Here, too, you need to pay attention to their integrity. If the dirt can still be removed with a cotton swab and alcohol, go with this option. For hard-to-reach places, you can use a cotton swab.
If the contacts are completely rusty or even rotten (which is not uncommon for an old flashlight), they will have to be replaced. Ask your electronics store if there are similar contact elements (for at least ten years, they have been absolutely identical in all flashlights with rare exceptions). If there are no similar ones, choose as similar an option as possible. Armed with a thin soldering iron, you can easily re-solder them.
Damage to wire contacts. In addition to the places described above, contacts are present at the places where the wires of the electrical circuit are soldered. Cheap production, haste during assembly and careless attitude of workers often lead to the fact that some wires are completely forgotten to be soldered, so the LED flashlight does not work, even if it is just out of the box. How to repair the flashlight in this case? Carefully examine the entire circuit, carefully moving the wires away with medical tweezers or another thin object. If a failed soldering is found, it must be restored using the same thin soldering iron.
The same can be done with flimsy connections, the characteristic condition of which is a torn bare core, barely attached to the joint. If you have enough time and resources, and you value this flashlight, you can methodically and efficiently re-solder all the contacts. This will significantly increase the efficiency of such a circuit, protect exposed elements from moisture and dust (which is important if the flashlight is a headlamp), and in subsequent cases of repairing the flashlight, this item will be eliminated. Repairing small LED headlamps is done exactly the same, the sizes are just different.
Damage to wires. Once you have ensured that the contacts are clean, you can begin to inspect all the wires in the circuit for damage or shorts. A common case is when, either during assembly at the factory or after a previous repair, the wiring was damaged by an incorrectly installed housing cover. The wire got caught between two housing parts and was cut or crushed while tightening the bolts. During the flow of current, the electrical circuit could overheat or even short out, this will inevitably lead to repair of the LED flashlight.
All torn sections must be soldered together to ensure better conductivity than with simple twisting. Do not forget to insulate all bare areas; it is best to use thin heat shrink. It is advisable to completely replace severely damaged wires, which may have already become rusty, with your own hands (select the appropriate wire). After such modifications, old lights can shine much brighter - the modernization improves the flow of current.
Faulty switch. Also pay attention to the contacts of the wires with the switch terminals and troubleshoot. The easiest way to find out if the switch is causing your flashlight to not work is to complete the circuit without it. Eliminate it from the circuit by directly connecting the battery to the LEDs (you can also try from the mains with a voltage corresponding to the battery). If they light up, change the switch. Perhaps it has already mechanically broken down from repeated use, the flashlight just turns off, or there may also be a manufacturing defect. If the LEDs do not want to light up directly from the battery, we proceed further.
Lack of current in the network. The most common cause of such a malfunction is a discharged or very old lithium battery. The LED flashlight can glow when charging, but if it is unplugged from the outlet, it immediately goes out. A complete malfunction is observed when the flashlight does not charge at all and does not react in any way when turned on, although the charging indicator lights up steadily.
LED failure. Once all the problems with the wires are fixed (or there were none), turn your attention to the LEDs themselves. Carefully remove the board on which they are soldered. Use a multimeter to find out the current going into and out of the board. If possible, check the contacts on the entire board. Most likely, the LEDs are connected in series, so if one breaks, the others will not light either. Checking each one, if there are 3 or more of them, takes quite a long time, so it is better to immediately buy new LEDs.
Board with LEDs
Conclusion
Many cheap Chinese LED flashlights, assembled under conditions of austerity, are most often susceptible to electrical circuit failures. Wires with a very small cross-section are installed there, which are quite problematic to solder even with a good device. However, almost all problems with wires and batteries can be easily fixed at home; with the right and careful approach, even an inexpensive repaired flashlight will last you more than three years of constant use.
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 housing 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 a little 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 straight, 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 “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 into 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