EC1204 Pv1.2 Electronic welding assembly Tutorials Welding sequence: low to high Note: Step 5 and Step 7 can not turn, or not assembled welding. Step 1: Complete SMD components welding; following two charts PNP Transistor：Q1、Q6、Q7、Q8、Q9、Q10、Q11、Q12、Q13) 10K Resistor：R6、R12、R14、R16、R18、R20、R26、R29、R31、R32、R33、R34、R35 47 ohm Resistor：R5、R11、R13、R15、R17、R19、R25、R27、R30 20pF apacitance：C3、C4 104 capacitance：C2、C5 PNP Transistor：Q2、Q3、Q4、Q5 10K Resistor：R1、R2、R3、R4、R21 47 ohm Resistor：R7、R8、R9、R10 20pF capacitance：C6、C7 Step 2: Welding and 32.768KHz 12MHz crystal oscillator, cut excess pin flat 32.768KHz crystal shown above is recommended for welding, so you can hold the crystal. Step 3: torch lights installed, note the location of the + and red light installation,D5*、D10*、D15*、D20*、D25*、D30*、D35*、D40*、D45*、D50*、D55*、D60* are the red lights. after assembling books and other things to suppress the formation of all the lights, and then rewind over and solder one pin of a pin, finished weld 60 LED lights will cut all of its pins Step 4: Welding sensor DS18B20, cut flat extra pins. Step5: Welding three buttons RST, MODE, PLUS; 8-pinIC socket U2;40-pin IC socket U1;battery holder BT1. Step 6: 8-pin IC cut flat seat and battery holder on extra pins Note: This step must be, otherwise the back of the LED will not be assembled. Step 7: Welding at DS1 digital tube, cut flat extra pins, note the direction of digital tube placement, upside down LED will not be displayed. Note: The four dots digital control word to be heading EC1204B V1.2 side, as indicated by an arrow Step 8: Welding 6-pin pin, note: four 6-pin pin pin pad next to the reserved, no welding. Step 9:buzzer(SPEAKER),100uFcapacitor-C1,miniUSB-USB; Cut flat extra pins. Note: mini USB USB interface is directional and must be assembled as shown in the following diagram, otherwise it will reverse the positive and negative power supply system, causing burn chips Note the direction of welding miniUSB Step 10: Install AT89S52 microcontroller, DS1302 clock chip, battery, pay attention to the direction of the chip gap. Following chart shows the arrow: front elevation back elevation