5300

Assembling XR2206 IC based function generator kit

Introduction
Function generator is one of the most important instruments of an electronics laboratory. It is used for repairing and designing electronic circuits. It is used for testing electronic devices  as well. Purchasing a new function generator from the market  is not a big problem but not every electronics learner and hobbyist can purchase a new function generator like me due to their high costs. So for electronics learner's and hobbyist cheap function generators are available as DIY kits. XR2206 Function Generator kit is one of them. Although It is not as effective as a commercial one but it can be used to fulfil all the requirements of  an electronics learner and hobbyist. Also the XR2206 function generator kit has very less features in comparison to a function generator that  is used in electronics laboratories.

Features of XR2206 Function Generator Kit
  • Low Cost (about 7$).
  • Available in both pre soldered and solderable form.
  • Small size and weight.
  • Transparent case for for protecting the kit.
  • Frequency Adjustable.
  • Amplitude Adjustable.
  • Cable of generating sine, square and triangle wave signals.
  • Operates on 9V DC power supply.
  • Instruction manual is included in the kit.
  • All the components are THT(soldiering process is easy).
  • Easy to operate.
 
List of Components (Included in the kit)

Resistors
  • R1------->1k
  • R2------->50k
  • R3------->5.1k
  • R4------->330
  • R5------->5.1k
  • R6------->5.1k
  • R7------->50k
  • R8------->100k
Capacitors 
  • C1------->100uF
  • C2------->0.1uF(104)
  • C3------->10uF
  • C4------->10uF
  • C5------->1uF(105)
  • C6------->0.047uF(473)
  • C7------->0.002(222)
  • C8------->100pF(101)
Integrated Circuit(IC)
  • U1------->XR2006(DIP-16 package)
DC power jack
Male headers
  • J3------->2x5
  •  J2------->2x2
PCB Terminal(3 Pin)
Jumpers
PCB
Transparent Acrylic Case
M3 Nut & Bolts
Potentiometer knob


Necessary Tools for Assembling the kit
For assembling this function generator kit following tools are compulsory.
  • Soldering Iron (60W)
  • Soldering Wire (0.8mm)
  • Soldering Flux
  • Screw Driver
  • Wire Cutter
  • Acetone ( For cleaning the PCB after soldering)
  • Brush

XR2206 kit PCB (Printed Circuit Board)
elektor
elektor

For Assembling the kit go through the following steps
 
Step-1: [Soldering Resistor]

This is the first step of whole soldering process. In this step we solder all the resistors included in the DIY kit on PCB. Before soldering the resistors we find their values. For finding the resistors values we can take the help of following resistors colour code chart:
elektor
After finding the values of all the resistors we can easily identify which are R1, R2, R3,.............R8. Mount all the resistor on the PCB as shown below:
elektor
Resistors do not have polarity so we can solder them without caring about their polarity. Bend the leads of all resistors so that they can not leave their places before being soldered.
elektor
Now make solder joints and cut out the excess leads of the resistors with the help of a wire cutter.
elektor

Step-2: [Soldering Ceramic Capacitors]
In this step we have to solder all the ceramic capacitors. Like resistors ceramic capacitors do not have polarity also, so we can easily solder them on the PCB easily.
elektor
Make solder joints and cut out the excess leads of the ceramic capacitors.
elektor


Step-3:[Soldering Electrolytic Capacitors]
In this step we solder the electrolytic capacitors. The Electrolytic capacitors have polarity so before mounting them on the PCB we need to find their positive and negative leads. Generally The longer lead of the electrolytic capacitor is +Ve and shorter lead is -Ve. After finding the polarity of electrolytic capacitors mount them on the PCB as shown below:
After mounting all three electrolytic capacitors bend their leads and make solder joints. After making the solder joints cut out their excess leads:
elektor
elektor

Step-4:[Soldering 2x5 & 2x2 Male headers]
In this step we solder 2x5 & 2x2 male headers. For this mount both of them on the PCB  as shown in the given fig.
elektor
make the solder joints. Unlike resistors and capacitor male headers do not have excess leads so here we do not need to cut excess leads.
elektor


Step-5:[Soldering DC Jack]
In this step we solder the DC power jack. Mount the jack on the PCB as shown in the following Fig.
elektor

Now make solder joints. During soldering DJ jack please increase the temperature of soldering iron otherwise solder joint would not be clean.
elektor

Step-6:[Soldering IC holder]
In this step we solder the IC holder. Before mounting the IC holder on PCB please keep the cut mark  (Notch) of IC holder at top side and flat side towards bottom side.
elektor
 
elektor


Step-7:[Soldering Potentiometers]
Before soldering the potentiometers we need to Identify their vales. The left and right potentiometers are of 50k and middle one is of 100k.
elektor
After finding the vales of potentiometer mound them on the PCB and make solder joints
elektor


Step8:[Soldering PCB Terminal]
In this step we solder the 3-pin PCB terminal. This is the last component left for soldering. Mount the PCB terminal on the PCB as shown in the following fig.
elektor
After mounting the PCB terminal make solder joints.
elektor


Step-9:[Cleaning the PCB with Acetone]
In this step we clean the PCB board with acetone and plastic brush. It is necessary because during soldering, soldering flux makes the PCB board dirty. After cleaning with acetone it looks as clean as new PCB.
elektor


Step-10:[Preparing the Acrylic Case]
A transparent acrylic case is also provided in the kit to keep the PCB save. M3 nut & bolts is also included in the kit for fixing the PCB on the bottom acrylic sheet.
elektor

Remove the protecting layers of acrylic case insert M3 nuts as shown in the Fig.
elektor

Mount the Function generator PCB on the kit with the help of nuts & bolts. Use screw driver to tight the nuts.
elektor

set the potentiometers to initial position and fix the potentiometers knobs as shown in the Fig.
elektor


also attach all four side layers as shown.
elektor

Now put the top acrylic sheet and tight it with screws and screw drivers.
elektor

Now our KR2206 function generator kit is ready to use and it looks really nice.
elektor