Introduction: Detailed Instructions for Electronic Dice

About: Retired Electronic Design Engineer. Member of The MakerBarn.

This is a common kit available from suppliers on eBay. It is an excellent project for teach soldering skills. Like most of these kits, there is very little documentation. In fact, this kit came with a sheet of paper totally in Chinese. Interesting, but not really useful.

We bought a large number of these kits for Maker Camp at The MakerBarn. Assembly instructions had to be written, so why not do it as an Instrcuctable so that everyone could make use of them.

Step 1: Materials and Tools

This is a photo of a typical kit. The bill of materials is as follows:

1. Blank printed circuit board

2. 3ea 470 Ohm Resistor R8, R8, and R10

3. 1K (1000) Ohm Resistor R7

4. 9ea 10K (10,000) Ohm Resistor R3, R4, R5, R6, R12, R13, R14, R15, and R16

5. 3.3M (3,300,000) Ohm Resistor R2

6. 4.7M (4,700,000) Ohm Resistor R11

7. 10M (10,000,000) Ohm Resistor R1

8. 104 (0.01uF) Disc Capacitor C2

9. 1uF Aluminum Electrolytic Capacitor C1

10. 7ea 5mm Red LED D1, D2, D3, D4, D5, D6, and D7

11. Push Button Switch S1

12. 3ea S8050 NPN Transistor Q2, Q5, and Q5

13. 2ea S8550 PNP Transistor Q1, and Q3

14. NE555P Timer IC (8 pin) IC1

15. CD4017 CMOS Counter IC (16 pin) IC2

16. 8-Pin IC Socket for IC1

17. 16-Pin IC Socket for IC2

18. 2-Pin Power Connector

19. 2-Conductor wire with connector

Tools Required

1. Soldering Iron suitable for printed circuit boards

2. Solder

3. Diagonal Clippers for cutting component leads

4. Small needle nose pliers for lead bending

5. A holding fixture such as a "Third Hand" is not necessary, but helpful

Step 2: Resistors R1, R2, R7, and R11

These four resistors are all of different values, so look very closely at each resistor under good lighting to make sure it is the proper value. Insert the resistors into the PCB and solder on the back side.

R1 - 10M Brown, Black, Black,Green, Brown

R2 - 3.3M Orange, Orange, Black,Yellow, Brown

R7 - 1K Brown, Black, Black, Brown, Brown

R11 - 4.7M Yellow, Violet, Black, Yellow, Brown

Solder and Trim

Step 3: Check Your Soldering Job

This photo shows what the solder should look like. Just a small amount of solder is all that is necessary. Too much solder can cause "bridges" that short connections.

Step 4: Install R8, R9, and R10

These resistors are all 470 Ohms. The color code is:

Yellow, Violet, Black, Black, Brown

Insert and Solder and Trim

Step 5: Install the 10K Resistors

Resistor R3, R4, R5, R6, R12, R13, R14, R15, and R16 are all 10K Ohm. The color code is:

Brown, Black, Black, Red, Brown

Insert, Solder, and Trim.

Step 6: Install the PNP Transistors

In this kit, S8550 PNP transistor were used. In other kits, a different type of PNP transistor may be used. Find the two transistor that are identical, they should be the PNP transistors.

Spread the leads slightly and insert each transistor into the PCB in position Q1 and Q3. Notice that the transistor has a flat side. Make sure the flat side on the transistor matches the flat side silk-screened on the PCB

Solder and Trim

Step 7: Install the NPN Transistors

The transistors Q2, Q4, and Q5 are NPN transistors. In our kit, S8050 transistors were used. Find the remaining three transistors and make sure they have identical markings.

install the transistors in the Q2, Q4, and Q5 position. Make sure the flat side of each transistor matches the image silk-screened on the circuit board.

Solder and Trim

Step 8: Install the Capacitors

There are two capacitors in the kit. One is a small disc capacitor marked 104. Insert this device into position C2.

The other capacitor is a larger type called an Aluminum Electrolytic. This capacitor is polarized, which means it must be installed a certain way. On one side of the capacitor you will see a white line with - signs on it. This is the - (minus) side. The other side is the + (positive) side. looking closely at the PCB, you will notice the round symbol for C1 with one half with diagonal white lines, this is the - (minus) side. The other hole is marked with a +. Insert the capacitor with the + and - sides in the corresponding holes.

Solder and Trim

Step 9: Install the IC Sockets

Each IC has a socket. Notice that each socket has a small notch in one end. Insert the sockets in the board making sure the notch in the socket matches the notch on the silk-screened PCB. Do one socket at a time. It is best to solder only a single pin of the socket. Then, while pressing on the top of the socket. re-melt the solder and let the socket snap down tight on the PCB. Then solder all the remaining pins. The sockets leads do not require trimming.

Step 10: Install the LEDs

In the photo of an LED notice the Anode side of the LED has a longer lead. Opposite the Anode side is the Cathode lead. The Cathode side has a small flat on the body of the LED. Looking at the PCB, notice that at each LED position, there is a circle with a bar on one side. The bar side is where the cathode (flat side)goes. Insert one LED at a time. First solder one lead, press on the LED and re-melt the solder. The LED will pop into place, tight against the PCB. Solder the other lead and trim the leads. Do the same for all seven LEDs.

Step 11: Install the Push-button and the Power Connector

Snap the push-button switch into the PCB. Be careful, don't bend the leads. You may have to straighten the leads a bit to get them into the board. The switch should flat on the PCB. Solder, trimming is not necessary.

Insert the power connector. Make sure the notch in the power connector faces down, as in the photo. Solder one side, press and re-melt (as you did with the LEDs), then solder the remaining lead. No trimming necessary.


Step 12: The Finished Product

Carefully insert the ICs into their sockets. Each IC has a small notch on one end, make sue it aligns with the notch in the socket. Inserting an IC the wrong way can damage it when power is applied.

Plug the power wire into the connector on the board. The red wire should be to the left, as in the photo.

Makerspace Contest 2017

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Makerspace Contest 2017