We make Christmas decorations from LED strips. Excellent small LED tree Base board soldering
| amount | Designation and marking of the part on the diagram | |
| 6 | × | 10K resistor R1, R3, R5 on both boards |
| 6 | × | 330 ohm - 3K resistor R2 (2K), R4 (1K), R6 (330) on both boards |
| 1 | × | 2K resistor R7 (on one board only) |
| 6 | × | 47uF capacitor C1, C2, C3 on both boards |
| 6 | × | 9014 transistor Q1, Q2, Q3 on both boards |
| 13 | × | Red LEDs D1-D6 on both boards and D19 (only on one board with R7) |
| 12 | × | Yellow LEDs D7-D12 (on both boards) |
| 12 | × | Green LEDs D13-D18 on both boards |
| 3 | × | Printed circuit boards |
| 4 | × | Battery container with fasteners, power socket, switch and USB power cable |
Set composition
2. Scheme of a 3D Christmas tree and the theory of its work
The numbers of resistors and their rating are indicated on the board, if the rating is not indicated, refer to the table of the set composition. The value of the installed resistor is determined using a color code or by measuring the resistance of the resistor with a device.
Sets of 3D Christmas trees are equipped with pairs of resistors R2, R4, R6 with resistance values different from 1K. In any case, the lowest resistance resistor is installed in the power circuit of the green LEDs D1-D6, and the resistor of the largest resistance in the red LED circuit D7-D12. Putting a low resistance resistor in the power supply circuit of the green LEDs will make them glow a little brighter. Green LEDs are usually less bright than other color LEDs.
Do-it-yourself installation of resistors in the board
Biting off conductors
4. Installing transistors
Installing transistors on the board
Soldering the transistor on the board
Install the transistor from the board marking side. The position of the case must correspond to the drawing on the board. Solder transistors quickly without overheating. Solder all six transistors. Next, solder the electrolytic capacitors.
5. Soldering capacitors
Positive electrode is longer
Negative electrode marking
Polarity marking on the board
The capacitors of the radio designer are soldered
When soldering electrolytic condensates, the polarity of the latter must be taken into account. The negative electrode is marked on the body of the capacitor, and the lead itself is somewhat shorter than the positive lead. The negative electrode on the board is indicated by a shaded stripe. If there is no picture on the board, then the soldering pad for the positive electrode of the capacitor is usually square. When installing the capacitor on the board, consider its position on the board. Look at the photo. Next, install the LEDs on the board.
6. Soldering the LEDs
Installing the LED in the board
LEDs also have polarity when connected. The long electrode of the LED is positive and the short electrode is negative. Notice again the PCB markings and the square shape of the positive solder pad. When soldering, be sure all LEDs of the same color should be grouped together with a common resistor and transistor, as shown in the diagram. If you solder LEDs of different colors, then one color of the LED will glow brighter than the other color (and the other color may not glow at all!).
Pay attention to the position of the LEDs relative to the board. Diode D19 is not installed yet. After installing the LEDs, it's time to check the correct installation.
7. Checking the operation of soldered boards
After installing all the elements on the 3D Christmas tree board (with the exception of the D19 LED at the tip), the board must be tested. For this, 5 Volt power is supplied to the sites marked "-" and "+" on the tree stump. We insert the batteries into the container and, observing the polarity, touch the conductors to the power contact pads on the board. Watch the video. If all parts are installed and soldered correctly, then all LEDs should flash beautifully. If not, CHECK THE CORRECT INSTALLATION and correct the errors. Next, install the power and switching elements on the base board.
8. Soldering the base board
Correct position of the switch on the board
Installing a 3D Christmas Tree Power Socket
Battery container on the base plate
Soldering battery wires
We solder the 3D tree power switch button and the external power supply socket. Attention! When installing the power switch, the cutout side of the button should face the closest edge of the PCB, see photo!. A piece of a cut electrode from a resistor or capacitor is fixed on the board to the power supply socket. Such a loop will firmly fix the sockets on the board. We fix the battery container with screws and nuts on the back side of the base plate. See photo. The conductors from the batteries are shortened and soldered observing the polarity to the printed circuit board. Apply power to the board and check the voltage polarity at the pins in the center of the board. We proceed to the final assembly of the Christmas tree.
9. Final assembly
Electronic tree. Board assembly key
Connecting boards together
We collect two boards in a herringbone, the arrows on the boards should be nearby. Fix the position of the boards relative to each other by soldering one pad on the tree trunk.
Connecting three boards together
We insert the Christmas tree into the base PCB, following the polarity indications (“+” and “-”) on all three PCBs. Make sure the tree is installed correctly and solder the contacts and remaining pads on the tree trunk.
The 3D LED tree can be powered by battery pack or USB power supply. When the USB power plug is inserted, the batteries are disabled by the socket's internal contact, so the batteries can be left on when powered by USB.
Be careful when supplying USB power from gadgets and laptops, not all of them will be able to power the Christmas tree. Radioconstructor a set of parts for assembling a 3D Christmas tree you can purchase at the following link http://ali.pub/2rdf6t . How the tree glows, look at the video
Successful assembly of a 3D Christmas tree with your own hands.
As an add-on, only one Christmas tree can be installed on the base board. And connect the second board to the batteries or via a USB cable, for example, to a power bank. The board can be fixed on a headdress or on outerwear. The night will look very cool. Then from the set you get two Christmas trees.
On the eve of the New Year, I want to do something festive! And the best home decoration is everyone's favorite Christmas tree.
To achieve home comfort, we need: a small piece of wallpaper (or some kind of cardboard), green rain, adhesive tape and even hands.
We wind our sheet of paper in the shape of a cone and fix it with tape. Next, fold it and trim the bottom evenly so that it can stand straight. Then we take some copper wire (0.3..0.5mm) and wrap our cone, fixing the wire with tape, this will give it elasticity. We cut it in height (it is more convenient to install rows of LEDs). After the tiered (they are numbered in the diagram) installation of the LEDs, we fasten the section with tape familiar to us. We also place the board inside the Christmas tree. At the next stage, starting from the top, we wrap the cone with green rain so that the LEDs protrude a little. Well, by design...
As for the schema. We supply 7..12V (I think everyone has enough such blocks) to the stabilizer, to power the controller and make a common + (not stabilized) which is common to all LEDs. From this common wire, LEDs are switched on in parallel in each tier, we do this so that we do not have to pull two wires to each group of LEDs. At the outputs of the MK, 0 or 1 appear in turn, which go to the bases of the transistors to open them. Transistors are needed, since several LEDs are connected to each port of the MK, the controller may not draw all these currents. By the way, current-limiting resistors can be placed between the ports of the MK and the bases of the transistors. The LEDs are connected with a "minus" to the collectors (emitters to ground), and in front of their "plus" there are current-setting resistors. I think there should be no questions about the operation of the scheme ...
Transistors: BC547 (or any equivalent)
Current-setting resistors: 200 Ohm...1kOhm
Capacitors: any (these are power filters) from 0.1uF
In the diagram, the numbering (1-6) is our tiers of LEDs, starting from the bottom. The 6th is our top, an asterisk or something like that. Do not confuse, otherwise the glow pattern will disappear!
The application has a source code in, whoever wants can rewrite the program at their discretion.
List of radio elements
| Designation | Type | Denomination | Quantity | Note | Score | My notepad |
|---|---|---|---|---|---|---|
| MK AVR 8-bit | ATmega8 | 1 | To notepad | |||
| Linear Regulator | L78L05 | 1 | To notepad | |||
| bipolar transistor | BC547 | 12 | To notepad | |||
| Resistor | 10 kOhm | 1 | To notepad | |||
| Resistor | ~900 Ohm | 38 | To notepad | |||
| Capacitor | 0.1uF | 2 |
Good day to all! Before New Year there is still time, I decided to make a Christmas tree. As they say, I blinded her from what was!
And it was exactly:
- Copper tube 30 cm high with a diameter of 5-7 mm (iron can also be used),
- Copper wire with a diameter of 1-1.5 mm, I don’t remember how many meters, soft electrical tape “Japan” (Actually “Made in China”), I think it’s suitable and narrow tape,
- Heat shrink with a diameter of 4 mm,
- Copper wire (I used twisted pairs from UTP cable),
- 3mm LEDs (quantity depending on the number of branches on the future Christmas tree) green and red which were available, which were once ordered from a Chinese online store,
- Resistors (the value and quantity depends on the connection method and supply voltage, I soldered resistors from old circuits of phones, TVs, tape recorders),
- Pliers,
- Scissors or wire cutters
- Yarn "Grass" of green color was bought in the department "Yarn",
- Power supply (used an old phone charger)
- Resistor ratings, quantity and connection scheme can be calculated on the website: http://www.casemods.ru/services/raschet_rezistora.html
- The calculation of the multivibrator was done in the program "Symmetrical multivibrator"
Let's get started!
We measure the wire on the upper branches, make an allowance for attaching the branch to the trunk, fold it in half and twist the halves together. Thus, we get a branch blank:
The number of branches in the first row depends on your imagination, I made 4. Next, we attach the branches to the trunk with electrical tape.
We make the crown in the same way. Next, we make the second row of branches down. I have 6 of them, all made the same as the first ones, only they are a little longer, the number of branches in a row and the number of rows in a tree depends on you. Thus, you need to make and fix all the branches on the future Christmas tree.
If you do not want to make a garland, then you can immediately wrap the branches and trunk with Grass yarn. But I made a garland, or rather, even two separate ones. One garland of red LEDs and the second of green.
I soldered the LEDs in series in 2 pieces, a 120 ohm resistor 0.04 watts. Supply voltage 6 volts. There is one LED for each end of the branch. The tip of the branch was inserted between the legs of the LED. The wire from which the branches are made in lacquer insulation. After soldering, heat shrink was put on.
Before winding the branches, I checked the entire structure for operability (as you can see in the photo, this is already the second Christmas tree, and the third in the video at the end of the article).
The Christmas tree stand was made from a cardboard tube (the basis of a bobbin of packaging film). The top of the stand is cut out of chipboard, a hole is drilled along the diameter of the trunk, the chipboard is attached to a cardboard tube with nails, the bottom of the stand is sawn out of kragis. The barrel is fixed in the stand with hot glue. The stand is lined with black cashmere.
On the side of the stand, a hole for the power cable is drilled.
A multivibrator is inserted into the stand, calculated in the “Symmetrical multivibrator” program and soldered according to this scheme:
Everything is connected according to the scheme. After installing the multivibrator in the stand, we fix the bottom of the stand (cragis) with a furniture stapler. The tree is ready! Optionally, you can imitate snow on the branches with gouache.
Video of homemade Christmas tree:
On New Year's Eve, I want to decorate my house in an original way: not like the neighbors, and of course, not like “like last time”. With the help of the LED garlands offered for sale, you can create interesting compositions, but the price of the issue crosses out bold design decisions. Yes, and typical Chinese LED decorations look the same, and as a rule - faceless.
A smart solution is to create a garland with your own hands
- Firstly, it will be a 100% original product.
- Secondly, the decoration configuration will be exactly what you need.
- Third, it's a real money saver.
- And finally, you can safely say to family members, and especially children: “Daddy can!”
The concept is as follows: wires are stretched from the top to the lower branches, LEDs are arranged at the same interval, as if creating tiers.
The light must be dynamic: a control controller is required. Simple LEDs shine beautifully, but spot lights do not create volume. So you need shades for each LED element.
The calculation of the garland starts from the power supply. The option is purely individual: I used an unnecessary PSU from a laptop. The expected number of LEDs is no more than 100 pieces, when using standard 5 mm LEDs, the total current consumption (20 mA * 100) is 2 A at maximum brightness. For serial connection of 6 diodes (voltage drop on each of the order of 3 volts), the voltage of the power supply is 18-20 volts.
General calculation of the power of the garland:
We collect 5 lines. Each "thread" consists of 18 LEDs, 6 pcs. per channel (RGB option). 18 * 5 \u003d 90 pieces, total current 1.8 A. Thus, a power supply for a laptop with parameters: 19 volts, 4 amperes, is suitable. This provides a double power reserve.
Selection of necessary materials:
1. LEDs. I ordered for red, green and blue LED straw hat elements, the dispersion angle is 120 degrees.2. . Let's take a closer look at this element. If you don’t want to spend time making your own circuit (there are many options, the cheapest of them is on Arduino), you can take a ready-made controller for RGB tape. All circuits work on the same principle: 3 controlled channels, the switching sequence is set, and the brightness of the light. Actually, the three colors here are conditional, you can connect 3 channels of the same LEDs and enjoy the lighting effects.
To power the 19-volt channels, I chose a controller with a universal voltage of 12-24 volts. The control circuit is powered by any voltage in this range, at the output we get voltage.
A prerequisite (for my scheme) is the presence of a remote control for controlling modes.
3. Instead of a wiring harness, I chose (3 channels + 1 common).
4. different colors.
For ease of installation, I used 4 pin dupon connectors (2.54 mm pitch). The corresponding set has long been purchased from the same Chinese, an excellent help for various electronic crafts.
Since I planned to hide the LEDs in the shades, I bought it on Aliexpress. Landing diameter is 5 mm.
Calculation of the connection diagram
LEDs, even when connected in series (in my case 6 diodes), are connected through a current-quenching resistor. Parameters of LED elements on the package:
The calculation of the resistor is carried out according to the formula, or on the LED calculator. I used the online service:
- For the RED channel (voltage drop 1.8-2.0 V), the resistance is 420 ohms.
- For the GREEN and BLUE channels (voltage drop 3.0-3.2 V), the resistance is 82 ohms (green) and 75 ohms (blue). The green LED element shines brighter, so a higher value resistor to equalize the overall picture.
I bought a common anode RGB LED controller. That is, a minus is applied to each channel, and a plus to the common wire.
We collect a garland
You can use twisted wires, as on factory garlands. I liked the design on the train more.
We make a reinforced leg for each LED element. To do this, you need toothpicks and heat shrink.
We collect, we heat with a hairdryer.
It turns out this design:
It makes sense to immediately prepare and test all 90 LEDs.
Then we mark the cable, determining the installation sites of the diodes through an equal distance. I made neat cuts along the cable on the wires of the desired color, cut and tinned the mounting points.
After assembly, each LED looks like this:
It turned out neat and reliable.
It is convenient to solder on a device with a magnifying glass, which is called the "third hand".
Next, we connect the supply wire (common "+") to the channels, through resistors.
We isolate the parts with heat shrink.
And connect with the "plus".
We cover this loop with a large diameter heat shrink.
We mount connectors on the opposite end.
Then we put snowflake shades on the LEDs.
The lesson is not easy (after all, 90 pieces!), But fascinating.
We check again. The effect is amazing.
Note: Working LEDs do not work well in photographs, so the image is significantly worse than the original.
It remains to mount the garland on the Christmas tree - and call the kids: admire dad's work.
Outcome:
The total financial cost of the garland is no more than 1000 rubles. The main consumable part is a ready-made controller. The power supply is conditionally free. Diodes and wires are mere pennies. Additional costs: 300 rubles for snowflake shades. The option is not mandatory, but significantly increases the attractiveness of the garland.
The time spent (4 full days off) is absolutely not a pity: it was interesting to work, and the result is worth it.