PCBgogo

The printed circuit board is made into a fox shape and can be charged with solar energy. The eyes are two light-emitting diodes that emit amber light.

Things you need: 

Temperature adjusting electric soldering iron, solder, sharp-nosed pliers, his welding tool is very interesting, there are several crocodile clips that can turn the angle to help hold the weldment.

Circuit diagram  and components:

1.C2-47uF Ceramic Capacitor (Blue-large). 

2. C3-10uF Chip Capacitor (Blue-small). 

3. C4-0.1uF time scale Capacitor (Brown). 

4. U2-MCP6542 master IC. 

5. SC1 to SC6-BPW34 ($0.4135) photodiode. 

6. R5-330 ohmic resistor (orange band). 

7. R1/R2/R3/R4-10M resistor (brown and black tape). 

8. D1 and D2-Amber LED. 

9. Switch-single pole double throw switch. 

10. C1-0.033uF (black)

Start with capacitors and assemble our work. Although these capacitors look similar in appearance, it is important to weld the corresponding capacitors to the appropriate position! Second, these capacitors are positive and negative, so all you have to do is to position them. Let's show you how to read the numbers on the resistor. 

The number above the a.C2 is read as "476. the first two digits are its valid numbers, the third digit is the multiplier, and the common unit of capacitance is the leather method, so 476 represents the 47 * 10 ^ 6pF. 

The number above the b.C3 is read as "106", which means that the size of C3 is 10 * 10 ^ 6pF. 

The number above the c.C4 is read as "104", which means that the size of C4 is: 10 * 10 ^ 4pF

Resistor soldering 

The resistance has no positive and negative electrodes, bend their pins and insert them into the hole in the relative position of the circuit board. It is recommended that soldering begin with resistor R5.

Tip:

 it is usually welded on the back of the circuit board, but here in order to take care of the wearer's comfort, we weld on the front. 
Soldering fox's brain: chip. Note that before touching the chip by hand, touch a large metal object to release the static electricity that may be on your body and prevent static electricity from damaging the chip. The chip has a direction, pay attention to the small grooves at the edge of it.

Supercapacitor soldering 

The positive and negative electrodes of the storage capacitor are at the top, with a "-" symbol on the metal strip, and the positive electrode is at the bottom of the capacitor. Such a small component can make your fox run for 3 + hours!

Switch soldering

The welding of the switch also does not distinguish between positive and negative electrodes. 

Warning: the switch is made of ordinary plastic. If the soldering iron touches it, it will easily melt and damage the components.

LED soldering

Tips：Care to find the LED ，the long pin is the positive pole, the short one is the negative pole.

OK if everthing done，our fox can be work.
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