DIY strobe made from LEDs. Homemade strobe for ignition settings

Owners of carburetor cars are familiar firsthand with the difficulties of the ignition adjustment process. This is usually done by ear, which is not very convenient. Using a strobe light this process can be made easier. However, industrial devices are quite expensive, so many people make a strobe light for ignition with their own hands.

Disadvantages of industrial models

Industrial devices often have certain disadvantages that make the usefulness of the device highly questionable.

To begin with, the price for them can be quite significant. For example, modern digital models will cost a car enthusiast 1000 rubles. More functional models cost from 1700. Advanced stroboscopes cost about 5500 rubles. Needless to say, a car strobe light (made with your own hands) will cost a car enthusiast 100-200 rubles.

Often in factory devices, the manufacturer uses a particularly expensive gas-discharge lamp. The lamp has a certain lifespan, and after some time it will have to be replaced. And this in itself is tantamount to purchasing a new factory device.

Why is it worth making a strobe light yourself?

The shortcomings of factory and technological devices push the car enthusiast to independently manufacture this device. In addition, it is much cheaper to equip this equipment with LEDs instead of an expensive lamp. An ordinary laser pointer or flashlight is suitable as a source of diodes or a donor.

The remaining parts will also cost pennies. You don't need any special tools. The budget for the manufacturing process of a strobe light will be no more than 100 rubles.

How to make a strobe light with your own hands?

There are schemes and options for manufacturing great amount. However, for the most part, all projects to create this gadget are similar. Let's see what you need for assembly.

We will need a simple transistor KT315. It can be easily found in an old Soviet radio. The designation may be slightly different, but it doesn't matter. Thyristor KU112A can be easily obtained from the power supply of an old TV. You can also find small resistors there. Since we are making an LED strobe light with our own hands, we will naturally need LED flashlight. To do this, it is better to purchase the cheapest one from China. In addition, you need to stock up on a capacitor up to 16 V, any low-frequency diode, a small 12 A relay, wires, alligators, a 0.5 m long shielded wire, as well as a small piece of copper wire.

Assembling the device

The circuit is small, but you can place it right in that same Chinese lantern. So, it is advisable to pass wires through the hole in the back of the flashlight to power the device. It is better to solder crocodiles at the ends of the wires. You need to make a hole in the side wall, if the Chinese have not already made one. The shielded wire will be routed through this hole. At the opposite end, it is necessary to insulate the braid and solder the same piece of copper wire to the main core of the wire. This will be the sensor.

Device diagram and operating principle

Once current is applied through the power wires, the capacitor will charge very quickly through the resistor. When a certain charge threshold is reached, voltage will be supplied through the resistor to the opening contact of the transistor. The relay will work here. When the relay closes, it will create a circuit of a thyristor, an LED and a capacitor. Then, through the divider, the pulse reaches the control output of the thyristor. Next, the thyristor will open, and the capacitor will discharge to the LEDs. As a result, the strobe light, made with your own hands, will flash brightly.

Through a resistor and a thyristor, the base terminal of the transistor is connected to the common wire. Because of this, the transistor will close and the relay will turn off. The glow time of the LEDs increases, since the contact does not break immediately. But the contact will break, and the thyristor will be de-energized. The circuit will return to its base position until a new impulse is received.

By changing the capacitance of the capacitor, you can change the glow time. If you choose a larger capacitor, the DIY LED strobe will glow brighter and longer.

Device on a chip

The main part of this simple circuit is a DD1 type microcircuit. This is the so-called one-shot 155AG1. In this circuit, it is triggered only by negative impulses. The control signal will go to the KT315 transistor, and it will generate these negative pulses. Resistors 150 K ohm, 1 k ohm, 10 k ohm, as well as the KS139 zener diode work as amplitude limiters for the incoming signal from the car ignition.

A 0.1 mF capacitor together with a resistance of 20 kOhm will set the desired duration of the pulses that will be generated by the microcircuit. With such a capacitor capacity, the pulse duration will be approximately 2 ms.

Then, from the 6th leg of the microcircuit, the pulses, which by this moment will be synchronized with the ignition of the car, will go to the base terminal of the KT 829 transistor. It is here as a key. The result is a pulsed current through the LEDs.

How is this car strobe powered? With our own hands we need to run a couple of wires to the terminals car battery. It is imperative to monitor the battery charge level.

If you correctly assemble this simple circuit, you will immediately be able to see how the device works. If suddenly the brightness is not enough, then this is regulated by selecting the appropriate resistance.

You can use an old or Chinese lantern as a housing for the device.

Another strobe light circuit

This LED strobe, made with your own hands according to this principle, can also be powered from a car battery. Diodes will provide protection against reverse polarity. An ordinary crocodile is used as fastener here. It needs to be attached to the high-voltage contact of the first spark plug on the engine. Next, the pulse will pass through resistors and a capacitor and arrive at the input of the trigger. By that time, this input will already be turned on by a one-shot device.

Before the pulse, the one-shot device is in normal mode. The direct trigger output is low. The inverse input is, accordingly, high. A capacitor connected with a plus to the inverse output will be charged through a resistor.

A high-level pulse triggers a monostable, which switches the trigger and serves to charge the capacitor through a resistor. After 15 ms, the capacitor will be fully charged and the trigger will switch to normal mode.

As a result, the one-shot device will respond to this with a synchronous sequence of rectangular pulses with a duration of approximately 15 ms. The duration can be adjusted by replacing the resistor and capacitor.

The pulses of the second microcircuit are up to 1.5 ms. During this period, transistors are opened, which represent an electronic switch. Current then flows through the LEDs. A strobe light for a car works on this principle (whether it was made with your own hands or not does not matter - both devices shine the same way).

The current passing through the LEDs is much greater than the rated current. But, since the flashes are short-lived, the LEDs will not fail. The brightness will be enough to use this useful device even during the daytime.

This strobe light can be assembled with your own hands in the housing of the same long-suffering flashlight.

How to operate the device?

By assembling the device according to one of the given diagrams, you can simply and easily, and most importantly, accurately adjust the ignition on carburetor engines, check the correct operation of spark plugs and coils, and control the operation of the advance angle regulators.

To set the ignition as correctly as possible, it is usually assumed that the mixture is ignited a couple of degrees before the piston reaches the highest point. This angle is called the "lead angle". As the crankshaft speed increases, the angle should also increase. So, this angle is set at idle, and then it is necessary to check the correct setting in all operating modes of the unit.

Setting the ignition

We start and warm up the engine. Now we power our LED strobe and connect the sensor. Now you need to point the device at the mark on the timing case and find the mark on the flywheel. If the moment is broken, then the marks will be quite far from each other. By rotating the timing case, ensure that the marks match. When you have found this position, lock the distributor.

Then it's time to rev up. The marks will diverge, but this is a completely normal situation. This is how the ignition is set up using a strobe light.

So, we found out how to make a LED strobe with your own hands.

The interest of the modern motorist is not limited to attention to the car as a means of transportation. In many ways, the effect and impression that can be made on all participants in the movement is important. After a widespread ban on simulators of law enforcement and official car flashing lights, somehow unexpectedly the fashion for a strobe light on the grille and a double signal began to gain momentum.

Most of the above diagrams are not intended to fully simulate the signals of official cars; rather, this is purely for sporting interest. And to whom and for what to pay fines, everyone decides for themselves, based on their capabilities.

There are several simple ways to organize a strobe light on a car, it all depends on the amount of effort and money that can be spent on building a car strobe light. Most often they try to get the most realistic flickering of strobe lamps.

Several simple LED stroboscope circuits for cars have been tested in practice:

• according to the simplest scheme using two relays 494.3787;
• based on timer 555 and circuit k561ie8;
• on the PIC12F675 microcontroller;
• on the elemental base of 315 series transistors.

For your information! The safest and most popular way is to use the flashing effect by installing LEDs in your car headlights. It's beautiful and stylish.

Assembling a car strobe light with your own hands

The most in a simple way To build a reliable circuit for a car, you will use a couple of relays from the gazelle turn indicator system, a starter relay and a couple of trimming resistors. This strobe light circuit is easy to assemble with your own hands, and you don’t even need special knowledge or skills.

This diagram provides for connection to the car's daytime running lights system. If desired, you can switch the connected daytime running lights or strobe lights. The advantage of this approach is the absence of overload-sensitive electronic components in the circuit. The relays, even if the electrical circuit is overloaded, in most cases will remain intact, although they can lead to blown fuses.

To build a strobe circuit, the following is required.

1. First, we disassemble the housing of the turn relay and carefully remove the permanent resistor white with numerous transverse colored stripes.
2. In a variable resistance of 20-25 kOhm, solder the middle electrode to one of the side electrodes.
3. We solder in a variable resistance instead of the removed element so that after reassembly, the rotating rod of the variable resistor can be rotated freely.
4. We assemble the circuit and carry out a similar procedure with the second relay.
5. We assemble the circuit shown in the figure, and after applying the supply voltage, by turning the control rods, we select and synchronize the blinking frequency of the strobe lights on the car.

If you use a variable resistance of 450 kOhm, the blinking frequency will be much lower, but to more accurately select the blinking frequency, you can select several different resistances and achieve the required frequency.

Construction of a circuit based on a microprocessor

The most “advanced” car enthusiasts in the basics of microelectronics believe that the most effective would be a controller-based strobe circuit. On a PIC12F675 microcontroller, the circuit will be able to provide current pulses of up to one ampere with adjustable duration.

The strobe light circuit for a car is easy to assemble with your own hands. A package of light elements is most often used as a load, with the ability to change the flickering frequency of the LED strobe. The processor itself controls two powerful KT817 transistors and can produce seven different signal combinations. The system itself is quite common in industrial circuits of service flashers, especially for simple systems strobe lights on the car radiator grill.

The most unpleasant thing about connecting such circuits is the high sensitivity of any microprocessors to excess voltage or the occurrence of a short circuit. Therefore, when assembling and soldering, it is imperative to use a good grounding connection. In addition, the work requires the use of stabilized power; usually, for these purposes, a circuit with a paired low-voltage zener diode is used.

When connecting the strobe circuit to the car's electrical wiring circuit, you must first completely disconnect the power from battery, startup and testing of the circuit is strictly prohibited when there is no load.

DIY police strobe light on a logical counter

To obtain an effect similar to the flickering of LEDs in a strobe light on law enforcement service engines, you can use an interesting option on the 561 series logic counter and 555 timer. The circuit turns out to be somewhat more complicated than previous designs, but if you have a couple of hours of free time and the ability to solder, you can assemble a small homemade product on a printed circuit board.

Packages of LEDs with a total current consumption of no more than 3A are used as a load; if desired, they can be replaced with low-power halogen lamps with a total power consumption of up to 30 W.

The specificity of constructing such a strobe circuit using LEDs is an interesting feature of the formation of a control signal. The microcircuit on the 555 assembly acts as a source of the control signal supplied to the counter input. Without going into the specifics of how the strobe works, we can only note that the circuit for igniting and extinguishing the LEDs was copied from the strobe of a police car.

Rectangular pulses are fed to the counter and summed up. After a certain programmable time, the potential at the control contact changes from high to low.

A strobe works something like this: each of the LED packages flashes, gives a certain programmed number of flashes and goes out, then the signal is transmitted to the next LED package and so on in cyclic mode.

Important! Powerful KT819 or bipolar KT818 are used as control keys in the strobe circuit, which allows you to control large currents in the load.

For powering 555 chips maximum voltage The power supply cannot be increased more than 18 Volts; the stabilizer is not designed for a larger operating range, and the circuit remains operational even when the voltage drops to 5 V.

How to make a strobe light with your own hands using simple spare parts

The most budget-friendly way to build a LED strobe with your own hands is not to buy a bunch of spare parts on the radio market for a couple of thousand, but to try to use old Soviet or Chinese spare parts.

As a signal source we use a 155 series mikruhu, or AG1. After power is applied, the microcircuit sets a positive potential at the control pin, and as the capacitor charges, the potential drops and opens the control signal to KT315. The capacitance of the capacitor determines the length of the flash; at 0.1 µF it will be approximately 0.01 sec, which is quite enough to obtain the necessary optical effect.

On the 6th leg 155 of the microassembly, a series of pulses will be formed, coupled with pulses of the ignition system. They fall on the control electrodes of two KT 829 transistors. Next, the transistor opens, and a significant current flows through the load from the LEDs.

If the strobe circuit consumes more than 60 W, use standard aluminum radiators to cool the transistors.

The result, or the design of strobe LEDs for cars

For most fans of homemade strobe lights, sometimes it is more important to hide the fact of owning a homemade light illumination similar to a police one. Therefore, the package of light bulbs or LEDs is often removable so that it can be easily installed on the hood or roof of a car. Sometimes, for greater camouflage, an easily removable plastic cover is placed on top of such a block, appearance strongly reminiscent of a taxi lamp.

The advantage of this design solution is that the strobe device is easy to remove and even throw away. A strobe light with a plastic cover on top will resemble a taxi driver's flashlight and will not attract the attention of police in a parking lot or when a car accidentally stops on the road.

The second installation option is to install a package of strobe LEDs in the area of ​​the car's radiator grille or in the cavity of the headlight lamp. This is a more expensive and effective method, since it will require some alteration of the car’s optics, and in the event of a conflict with law enforcement officers, it may become the basis for placing the car in an impound lot.

In many stroboscope diagrams to determine the exact ignition timing they use IFC lamps and rather complex schemes for their “attachment”. I have proposed a relatively simple strobe design that is easy to set up and has no scarce parts (see figure).

R1C1R2VD1VD2 - a link that matches the high-voltage signal from the input of the device to the input of the DA1 microcircuit, which is timer 1006VI1 , connected according to the one-shot circuit. For each input pulse, a pulse appears at output 3, the lifetime of which is determined by link R3C2. Resistor R3 regulates the duration of the output pulse. An amplifier is assembled on transistor VT1.

A single-vibrator is assembled on element DA1, i.e. a waiting multivibrator that waits for input pulses from the high-voltage wire of the first cylinder. The sensor of these pulses is a regular clothespin, on one side of which a wire with a diameter of 0.1 ... 0.3 mm is wound.

The number of turns is 30-50, this winding is securely fixed with “Moment” or “Super Cement”, “Globe” glue, etc. The surface of the winding is protected with ordinary electrical tape so that the clothespin is securely closed or opened. A wire, preferably shielded, is soldered to one end of this winding. The wire shield is connected to ground in the main circuit. Elements R1 C1 R2 R3 match the signal from the sensor with the input of the microcircuit. The duration of the output pulse is controlled by link R3C2. Transistor VT1 turns on and off directly the LEDs HL1-HL9. The LEDs should glow bright white. LEDs do not have a specific brand.

The duration of the output pulse should be within 0.5...0.8 ms. If it is more, then the LEDs will not last long, and the marks on the flywheel or on the crankshaft pulley will be “blurred”. When adjusting, the engine speed should be kept within 850... 1700 min -1. Before adjusting, it is better to mark the speed with reflective paint.

It is advisable to use parts of the smallest possible sizes; the dimensions of the board depend on this. Mica capacitor C1 or K73-11, K73-17 with an operating voltage of at least 500 V. LEDs must first be checked for operation. Their installation on the board should be concentrated in one place in order to maximize the radiation flux. Dimensions printed circuit board depend on the specific device into whose body the performer wants to “attach” a strobe. I placed the strobe light in the body of a flat electric flashlight. In addition to the sensor wire, which was mentioned above, you need to enter the +12 V and ground wires.

The assembled device must be checked so as not to damage the LEDs, which are the most expensive elements on the board! Instead, you should turn on any LED and a 1.5 kOhm resistor connected in series. Connect the wires, attach the sensor wire to the high-voltage wire of the first cylinder.

Wires must not touch moving parts of the engine! Start the engine and watch the LED glow. Using an oscilloscope, check the pulse duration at pin 3 of DA1; if it is within 0.5...0.8 ms, then the circuit is working and you can safely connect the LEDs. Connect only with the engine switched off!

Disconnect the vacuum hose from the ignition distributor. Do everything necessary connections. Start the engine and point the strobe beam at the crankshaft pulley or flywheel. Observe the marks in the appropriate places according to the technical description of the specific vehicle. If the marks are in place, then the ignition timing is set correctly. If not, adjustment will be required. Increase engine speed and watch the marks move. This states that the centrifugal ignition timing control is working. Carefully connect the “vacuum”, watch the position of the marks move. If there is a change, then the distributor vacuum regulator is working.

E.L. Vyuga, Cherkassy

If you like to do the maintenance of your car yourself, then to reduce the cost of purchasing a tool, you can make a strobe light for ignition yourself.

What is a strobe

A stroboscope is a device for observing objects making rapid, periodically repeating movements. To do this, it illuminates a moving object with bright flashes of light, repeated with a frequency equal to the frequency of movement of this object. In this light, a moving object appears motionless. In a car engine, using a strobe light, you can determine the ignition timing angle. To do this, you need to synchronize the flashes with ignition pulses in the first cylinder, and direct the light to the TDC and ignition timing marks, illuminating the crankshaft pulley with a mark.

Factory-made stroboscopes usually have an inertia-free flash lamp as a light flash emitter, which allows you to adjust the ignition timing even in bright sunlight. However, it has a short service life and is not always on sale. Therefore, with the advent of LEDs with a luminous intensity of more than 2000 mcd, it became more convenient to use them when making a strobe light with your own hands. To convince us of the significant superiority of the luminous flux parameters of the new LEDs, let us recall that the AL307, with the same current consumption, has a luminous intensity of only 10–16 mcd.

(diagram for video materials in the description under the video)

Materials

The strobe circuit proposed for making it yourself is simple and does not require complex settings. To make a simple strobe for adjusting the ignition timing with your own hands, you will need the following tools, parts and materials:

1. Pocket flashlight with a large enough battery compartment.
2. LEDs KIPD21P-K – 9 pcs.
3. Chip K561TM2 (two two-stage D-triggers). Russian analogues: K176TM2, 564TM2; imported analogue – CD4013/HEF4013.
4. Transistor KT315B – 2 pcs. (VT1, VT2); KT815A – 1 pc. (VT3).
5. Trimmer resistor SPZ-196 or SP5-1 with a resistance of 33 kOhm.
6. Fixed resistors 5.1 Ohm - 3 pcs., 3 kOhm - 1 pc., 15 kOhm - 1 pc., 20 kOhm - 2 pcs., 330 kOhm - 1 pc., with a power of at least 0.125 W.
7. Diode KD213 or any other medium power with U arr. max not less than 16 V.
8. Non-polar capacitors KM-5, K73-9 or others. C1 must have an operating voltage of at least 200 V, the rest not less than 16 V. 0.068 µF - 3 pcs., 47 pF - 1 pc.
9. Any toggle switch to turn on the power of the device.
10. 1 m of shielded wire (for example, antenna).
11. 3 alligator clips.
12. A small piece of foil PCB 1 mm thick.
13. Stranded double insulated copper wire – 1.5 m.
14. Glue gun.
15. Soldering iron, solder, flux.

Device design

The body of the strobe light will be a flashlight. The circuit is assembled by hanging installation. The finished circuit is filled with hot plastic from a glue gun, and after the filling has hardened, it is placed in the flashlight battery compartment. The power and signal cables are routed out through holes drilled in the housing. You need to solder clips to the ends of the power wires, indicating the polarity. Connect to the strobe input antenna cable. Solder an alligator clip to the central core of the input cable. After connecting the strobe to the car engine, it will use it to send synchronization pulses from the high-voltage ignition wire to the input. To make this possible, it is enough to put it on the insulation of the high-voltage ignition wire of the first cylinder of the car engine. The synchronization pulse will go through the capacitance formed by the central core of the ignition wire and the clamp. That is, a simple homemade capacitive sensor will consist of an alligator clip placed on a high-voltage wire.

It is most convenient to make a light emitter by mounting a group of LEDs close to each other in the center of a disk made of foil PCB. It should be installed so that the LEDs, having passed through the hole for the light bulb in the reflector, are as close as possible to the location of the filament. You can attach the textolite to the reflector using a glue gun.

Nutrition

The device is powered from the vehicle's on-board electrical network. Diode VD1 protects the device from accidental connection of reverse polarity power. The synchronization pulse from the capacitive sensor through the circuit C1, R2 is supplied to the input of the trigger DD1.1, turned on as a standby multivibrator. Pulse high level triggers the waiting multivibrator, the trigger switches, and capacitor C3, charged in the initial state, begins to recharge through resistor R3. After approximately 15 ms, this capacitor will recharge enough that the voltage at the R input will again reset the flip-flop to its original state.

So the waiting multivibrator reacts to each positive pulse from the capacitive sensor, producing synchronously with the input high-level rectangular output pulse of constant duration (15 ms), which is determined by the values ​​of resistor R3 and capacitor C3. The sequence of these pulses from the non-inverting output of trigger DD1.1 is supplied to the input of the second standby multivibrator, assembled according to a similar circuit on trigger DD1.2. The pulse duration of the second node reaches 1.5 ms and is determined by the parameters of resistor R4 and capacitor C4. The output voltage of the second trigger opens triodes VT1 – VT3, and current pulses of 0.7 to 0.8 A pass through the LEDs.

Some subtleties

Despite the fact that the current value is significantly greater than the permissible value for these LEDs (the maximum permissible direct pulse current is only 100 mA), there should be no fear of overheating and failure. Because the duration of the pulses is short, and their duty cycle in normal mode is no less than 15. The brightness of the flashes of nine LEDs allows you to use the device even during the day.

The editors of the Radio magazine report that in order to verify the functionality of the device, it was tested.

The LEDs successfully withstood a pulsed current of 1 A for an hour, and not even a slight overheating was detected. Typically, the operating time of the device does not exceed 5 minutes, and the current passing through them in this design is somewhat less.

The purpose of the standby multivibrator on the DD1.1 trigger is to protect the LEDs from failure when the crankshaft rotation speed increases. Typically, the device is operated at a crankshaft speed close to idle (from 800 to 1200 rpm). Since the duration of the flashes is constant, as the crankshaft rotation speed increases, the duty cycle of the current pulses through the LEDs will decrease, and, as a consequence, the heating of the latter will increase. Therefore, the duration of the pulses of the waiting multivibrator on the DD1.1 trigger is chosen such that when the crankshaft rotation speed reaches 2 thousand rpm -1, the duty cycle of its output pulse sequence approaches 1. With a further increase in the rotation speed, and with it the input pulses, the cessation occurs they synchronize the output pulses, and the node begins to generate a sequence of average frequency pulses, which is much less dangerous for LEDs.

Device setup

It has been experimentally established that the duration of flashes should be from 0.5 to 0.8 ms. With shorter flash durations, when setting the advance angle using a strobe, the feeling of a lack of light is great. If the duration is longer, then the moving mark seems to be smeared. It is easy to select the required duration with your own hands, without measuring, but guided only by visual sensations. It is regulated using trimming resistor R4. The circuit does not require any further settings.

Using the device

To set the advance angle (moment) with your own hands, use a device to illuminate the setting marks while the car engine is idling. One of them is located on the rotating parts of the car engine (on the crankshaft pulley or on the flywheel). The second mark is stationary, it is located either on the cover of the front part of the car’s cylinder block, or on the gearbox housing. If in the light of the device the movable mark appears to be opposite the stationary mark, the car’s ignition is normal and does not require adjustment of the timing (angle) of advance.

If the marks do not match, to adjust the timing, you need to change the position of the distributor accordingly. To delay the ignition timing, you need to turn the distributor in the direction of rotation of the slider, and to do it earlier, in the opposite direction. If sparking in your car is controlled by a microprocessor, look for a faulty sensor or entrust the solution to this problem to professionals.