Step #2: Insert the 1.0K ResistorPrevNext
- In the R8 location, insert the resistor with color code brown, black, and red.
- Bend the leads of the resistor to make it easier to solder it in when you turn the circuit board over.
- Solder the resistor in, and then clip the leads.
Step #3: Insert the Protection DiodePrevNext
- In the location D1, insert the 1N4001 protection diode. Make sure that the end with the band is matched up with the band on the silkscreen image.
- Just like the resistor, insert the diode and then bend the leads. This will make it easier to solder it in.
- Turn the circuit board over, solder in the diode, and then clip the leads.
Step #4: Insert the 5V RegulatorPrevNext
- In location IC2, insert the 7805 5V regulator.
- The regulator transforms the voltage from the battery's 9V to the proper 5V that can be used by the reader.
- Make sure that the flat side of the regulator is matched up with the flat side of the silkscreen image.
- Place the leads in, solder it, and then clip the leads.
Step #5: Insert the LEDPrevNext
- In the location LED1, insert the LED. The shorter lead of the LED is the negative lead, and the longer lead is the positive.
- Match the leads up with the (+) or the (-) on the silkscreened board.
- Solder it in, and then clip the leads.
Step #6: The 9V Battery HolderPrevNext
- Begin by threading the two battery holder wires through the hole in the corner and tie them in a knot. This helps to keep the wires from being pulled out.
- The red wire is soldered into the (+) hole, while the black wire is soldered into the (-) hole.
- Turn the PCB over and solder in the two power wires.
Step #7: Test the BatteryPrevNext
- Connect a 9V battery to the battery holder.
- Your green LED should light up, which means that the 5V power supply is working well.
- If it does not light up, check to make sure all of your solder joints are clean and secure. If they are, then test your battery with a multimeter and make sure that it is not lower than ~6V.
- Once you have verified the power connection, disconnect the battery before completing the rest of the assembly.
Step #8: Insert the Remaining 1.0K ResistorsPrevNext
- In locations R2 and R7, insert the resistors with color code brown, black, red into their spots.
- Remember, resistors are not polarized, so it does not matter which direction you place them in.
- Solder the leads in, and clip them too.
Step #9: Insert the Four 10K ResistorsPrevNext
- Insert the resistors with color code brown, black, orange into locations R3, R4, R5, and R6.
- Turn the circuit board over, solder the resistors in, and then clip the leads.
Step #10: Insert the 1Meg Resistor and the zener diodesPrevNext
- The resistor with color code brown, black, green should be placed in location R1.
- Solder this resistor in, and then clip the leads.
- The zener diodes should be inserted into D2 and D3. Make sure the black stripe on the diode matches with the stripe on the silkscreened circuit board.
Step #11: Insert the CrystalPrevNext
- In location X1, insert the 3.57 MHz crystal.
- It does not matter which direction you insert the crystal. Solder it in, and clip the leads if necessary.
Step #12: Insert the 18pF Ceramic CapacitorsPrevNext
- In locations C2 and C3, insert the ceramic capacitors.
- The direction that you insert these into the circuit board does not matter.
Step #13: Insert the Electrolytic CapacitorPrevNext
- In location C4, insert the electrolytic capacitor. These are polarized, so make sure the long lead goes into the hole marked with a (+).
- You can bend it over, just to keep it from protruding out so much.
Step #14: Insert the 74HC04 Hex InverterPrevNext
- In location IC1, insert the 74HC04 hex inverter chip.
- You will need to bend the leads of the chip in slightly to make them fit into the circuit board.
- Now, safely, slide the chip in so that the notch in the chip matches the notch in the silkscreen.
- Push it in, and then solder the chip in.
Step #15: Insert the other Ceramic CapacitorPrevNext
- In the location C1, insert the small yellow capacitor.
- It does not matter which direction you insert the capacitor.
Step #16: Insert the NPN TransistorPrevNext
- In location Q1, insert the PN2222 or 2N3904 transistor.
- Make sure the flat side of the transistor matches up with the flat side of the silkscreened image.
- Solder it in, and then clip the leads.
Step #17: Inserting the SIM Card HolderPrevNext
- Begin by heating up one of the SIM holder's pins and melting a tiny bit of solder onto it.
- Now hold the SIM card holder in place while reheating the pin with the solder.
- Slide the holder so that the pins align with the pads.
- Remove the soldering iron to secure this connection. Now just solder the rest of the pins for the holder.
Step #18: Attaching the DB-9 ConnectorPrevNext
- Sandwich the pins of the DB-9 Connector with the circuit board. Make sure you pay attention to which side has 5 pins and which has 4 pins.
- Solder the leads securely to the board.
Step #19: Finishing up!PrevNext
- Now you are finished. If you plan on utilizing an FTDI cable to connect to the board, solder in the 6-pin male header.
- Begin by disconnecting the 9V battery. Slide the holder away from the green LED (refer to the OPEN lettering), and the holder will pop open.
- Slide the SIM card in so that the contacts face up and the notched corner is on the bottom. Now connect the battery, and connect the DB-9 connector to the serial port.
- Now you are connected to the computer!