Created on: 18 March 2023
How to build a running light 555 4017 kit tutorial for beginners in electronics. How to solder a running light electronic kit for beginners. Step-by-step instructions on how to build and solder a running light electronic kit that uses light emitting diodes (LEDs) and two ICs with the part numbers 555 and 4017.
The following image shows the running light 555 4017 kit parts, as they are supplied. A PCB, or printed circuit board, is for soldering the electronic parts to in order to build the kit.
The electronic kit used in this tutorial has the part number or product code 555-4017-DIP-KIT, and description: Running Light 555 4017 Kit. The product code may vary, depending on where the kit is bought. There are many similar kits available that use the 555 and 4017 ICs. Some kits are a full LED chaser or Knight Rider LED display where one LED in an array of LEDs appears to move back and forth.
The kit used in this tutorial lights up a single LED in an array of LEDs to make it look like an LED is traveling in one direction, and then repeats from the beginning, as the following video shows.
The running light 555 4017 kit consists of electronic parts shown in the table that follows. These are the parts seen in the photo near the top of this page.
The image of the circuit board shows the electronic part reference designators for reference when looking at the table. Reference designators are the U1, U2, R1, R2, R3, J1, etc. markings on the board. Note that there are two parts marked J1. One is a pin header and the other is a jumper link.
|1||Running Light PCB||none||Running light 555 4017 printed circuit board.||PCB|
|1||NE555P||U1||555 timer IC.||Integrated Circuits|
|1||CD4017BE||U2||4017 decade counter IC.|
|2||470Ω||R1 and R3||470 ohm resistor, 1% tolerance. Markings are: YELLOW - VIOLET - BLACK - BLACK - BROWN||Resistors|
|1||1k||R2||1k ohm, or 1000 ohm resistor, 1% tolerance. Markings are: BROWN - BLACK - BLACK - BROWN - BROWN|
|11||3mm Red LED||D1 to D11||3mm diameter red light emitting diodes.||LEDs|
|1||200k||RP||200k ohm, or 200,000 ohm preset or trim potentiometer.||Potentiometer|
|1||100µF||C1||One hundred microfarad capacitor, 16V.||Capacitors|
|1||1µF||C2||One microfarad capacitor, 50V.|
|1||2 pin male header||J1||J1 with rectangle marking on the board. 2.54mm spaced 2 pin male pin header.||Header|
|2||Jumper Link||J1 and J2||J1 and J2 marked with a line on the circuit board. Jumper links made from cut-off component leads.||Jumper|
A soldering iron, solder wire and side cutters are needed to build the kit. In addition, a small pair of long-nose pliers and a helping hands magnifier are useful tools to have. A fan or fume extractor helps to clear soldering fumes from the work area. Another optional tool is a multimeter which can be used to check voltages and resistor values.
Whenever an electronic kit is built, it must be supplied with a power source in order to operate. Some kits may be supplied with a battery holder, or some other way of connecting power. The running light 555 4017 kit is supplied with a two pin header for attaching a DC (direct current) power source.
This kit is specified to operate over a fairly wide voltage range, from 3.3V to 12V. As can be seen in the video near the top of the page, the running light kit is supplied with power from a 9V battery connected through a breadboard. This is just one example of how to power the electronic kit circuit. There are several other options to supply power to the kit.
Some suggestions of how to supply power to the kit follow. Whichever method is used to power the board, the point is that some additional parts are needed in order to do this. Take into consideration that you will need to buy the extra parts when purchasing the kit if you do not already have these parts available.
One way to power the circuit board is to solder a battery clip directly to the board instead of using the J1 pin header. A 9V battery can then be plugged into the battery clip to power the circuit. With this method, the power can't accidentally be connected the wrong way around once the battery clip is soldered in correctly.
If the J1 pin header is soldered into the board, then a suitable connector is needed to connect from the pin header to the power source. In the video, two male-to-female Dupont wires connect from the J1 header pins to a breadboard. The battery clip is then connected to the Dupont wires via the small electronic breadboard.
Battery holders are available with a 2-pin female connector that has a 2.54mm pitch. This connector fits directly onto the J1 pin header. It is important to connect the battery holder the correct way around. Accidentally reversing the battery polarity will most likely destroy the circuit. In addition, make sure to get a battery holder with the correct connector. This must be 2.54mm spaced and not 2mm spaced.
Another way to power the circuit is to use a 5V breadboard power supply. Connect the power supply to the circuit using Dupont wires, either directly, or via a breadboard. Direct connection requires two female-to-female Dupont wires.
There are many other ways of powering the circuit, such as using a mains to DC power supply that supplies a voltage between 3.3V and 12V.
Below is the circuit diagram of the running light 555 4017 kit. Click the diagram for a bigger image.
Beginners who are new to soldering must first read the article on soldering for beginners and the article on soldering irons for beginners. In addition, see how to solder a resistor from the electronic flashlight kit tutorial.
Continue to read below to see how to solder a running light 555 4017 kit after reading the above soldering tutorials. It is assumed that you know how to make a solder joint from the above links before you continue.
Before continuing, make sure that you have the exact same kit as the one used in this tutorial. If you do not, then be sure to make the necessary changes to the instructions that follow for the kit that you are using. A similar kit will be assembled in a very similar way, even though there are some differences in the circuits.
When soldering parts to a circuit board it is usual to solder the lower profile, or lower height, components first. This is because if taller components are soldered in first, it is more difficult to place the shorter components afterwards. Hence we start soldering the resistors first.
Solder the resistors in any order, but be sure to put the correct value of resistor in the correct place on the board. First select the correct value of resistor by looking at the resistor color chart. If you are not 100% confident that you read the resistor correctly, then check the value using a multimeter set to the ohms (Ω) scale. Measured resistor values will seldom if ever be exactly the same value as the value on the color bands. This is because when resistors are manufactured, the manufacturing process is not 100% accurate, but within a certain tolerance. Bear this in mind when making resistance measurements.
Resistor values for this specific kit are as follows:
Be sure to match up the correct resistor values to the correct position on the board. If your kit is different, then make the necessary changes.
If the resistors are attached to paper tape, first cut the resistors from the paper tape using side cutters. Cut near to the paper tape so that the resistor legs are as long as possible. Bend the resistor legs down as the following image shows at the right. Afterwards, insert the resistor into the correct position in the board. The image below shows resistor R2 soldered near the top left of the circuit board as an example of what to achieve. It is the 1k ohm resistor.
After inserting the resistor into the board, bend the resistor legs out slightly to prevent it from dropping out of the board when it is turned over. Turn the board over and solder each resistor leg in turn, as the following image shows.
After soldering both legs of a resistor into the printed circuit board or PCB, use side cutters to cut the excess length of each leg from the bottom of the board above each solder joint. Be sure to keep the resistor leg offcuts, as they are used as jumper links in the next step.
Correctly identify, insert and solder each remaining resistor to the PCB. The following image shows the resistors soldered to the PCB and the wire resistor leg offcuts.
Don't solder a jumper wire into the J1 position at the bottom right corner of the board in the above image – these J1 holes are marked in a rectangular box. This is for the header pins. Jumper wires are soldered to the J1 marked in the middle of the board towards the top of the above image. In addition solder a jumper wire to J2 at the bottom of the above image, near the left of the middle.
Use long-nose or similar pliers to bend two wire jumper links using the resistor leg offcuts from the previous step. Below is an example of a wire link bent using half-round-nose pliers. Look at the J1 and J2 wire link positions on the PCB to judge the width of each link. Bend and fit each link. Adjust each link width to fit by bending and checking against the PCB. Make adjustments if necessary, until each link fits.
Fit and solder each wire link in turn. After inserting a wire jumper link into the PCB, bend the legs out slightly and turn the board over. The image below shows a wire link fitted and legs bent out.
Use side cutters to cut off the extra length of each of the jumper wire link pins after soldering each jumper wire link pin. Both links are soldered into the circuit board in the following image.
Integrated Circuits or ICs are the 8-pin 555, marked U1 on the board, and 16-pin 4017 marked U2 on the board. These ICs must be oriented in the correct position on the board. The small half-circle notch marking on the IC outline on the board is an indicator that shows the orientation of the part. A notch at the end of each IC chip must be placed above the same notch marking on the PCB when inserting the IC chip into the board.
The following image shows that IC pins are bent at a slight angle outward, which means that the pins are spread too wide to go into the holes in the PCB.
The solution to the bent IC pins is to place the IC on its side and gently press down to straighten the pins 90 degrees to the IC body, as the next image shows. Turn the IC over and gently press from the other side as well if necessary.
Once the IC pins are close to 90 degrees to the body, the IC pins will line up with the holes in the PCB, and the IC will fit into its place on the printed circuit board. Solder one IC at a time to the board as follows.
Insert an IC into the board, making sure to orient it in the correct direction by using the notch markings. Turn the board over and solder one of the pins at the end of the IC. Pick the board up in one hand and press down on the top of the IC with a finger from the same hand while heating up the single solder joint on one of the end pins. If the IC was soldered in skew, it will snap into position from the pressure of the finger behind it when the solder joint melts. Allow the joint to cool and then place the board upside down on the work surface.
Solder the remaining pins of the IC on both rows of pins. It is not necessary to trim the ends of the IC pins under the board using side cutters, as they are relatively short. Solder the second IC using the same method described above. Refer to the next image to see the orientation of the ICs on the board.
It is important to insert the LEDs into their places on the board with the correct orientation. That is, the longer LED pin goes into the hole marked with the plus sign (+). The LED in the below image is oriented in the correct way to be inserted into any of the LED positions D1 to D10, with the longer lead at the + sign hole.
Solder LEDs D1 to D10 into the board after inserting them as described below. Finally solder LED D11, again make sure that the longer LED pin goes into the hole marked with the + sign.
Either insert all LEDs D1 to D10 before soldering them as the following image shows, or do one at a time. After soldering, use side cutters to cut the excess pin length off each LED.
The next image shows a top and bottom view of the PCB with D1 to D10 soldered in place.
Solder the remaining parts to the running light 555 4017 kit PCB by order of height as follows.
Solder the 3-pin trimmer potentiometer, or trim pot, marked RP to the board. Solder one pin at first and then check that the trim pot is positioned straight. If it is skew, melt the solder joint while pressing on the top of the trim pot to snap it into place. Solder the remaining two joints.
The J1 header pins can be soldered to the board, or a battery clip can be soldered instead. If soldering the pin header, insert the 2-pin header J1 into the board and solder the two pins.
If soldering a battery clip directly to the board, first check that some of the insulation is stripped from the end of each battery clip wire. Insert the wire tip of the red battery clip lead into the J1 hole marked + and solder it. Insert the tip of the black battery clip wire into the J1 hole marked – and solder it.
Insert the 1µF capacitor into the C2 position with the longer lead placed in the hole marked +. Solder the capacitor in place and trim the excess lead length.
Insert the 100µF capacitor into the C1 position with the longer lead placed in the hole marked +. Solder the capacitor in place and trim the excess lead length.
The following image shows the finished running light 555 4017 kit PCB after completion of all of the soldering.
Check the solder joints and orientation of all of the components on the board before powering up the board. Be sure to connect power correctly with positive of the supply to the + J1 pin and negative of the supply to the – J1 pin, as described in the next section.
Finally power up the board using a DC power supply that has a voltage between 3.3V and 12V. Don't connect the power supply to the board the wrong way around, or it will be destroyed. The image below shows the board powered from a 9V battery that is connected via a breadboard and two Dupont wires.
Look carefully before connecting a 9V battery that the battery is the correct way around. Although the battery won't clip into the battery clip the wrong way around, pressing the battery to the clip the wrong way around will still put power onto the circuit while the battery is held against the clip. This will destroy the circuit as there is no reverse polarity protection.
Be sure to connect the red positive lead of the battery or other power supply to the J1 pin marked + (plus). Connect the black negative lead of the battery or other power supply to the J1 pin marked – (minus).
If all of the parts are soldered in correctly the LED light display will start operating as the video at top of this page shows.
If there are problems: