XR2206 Function Generator Kit

Joshua R. T. Purba
Electronics

I have completed my build of a kit I bought last year: XR2206 function generator.

The completed build of XR2206 function generator kit.

The completed build of XR2206 function generator kit.

Look how tiny it is. It is comparable in size with my 12V DC wall wart. Kit dimensions: 5cm × 6.5cm × 3.5cm (including molded case and potentiometers' knobs).

It is so tiny.

Oscilloscpe displaying AC coupled sine wave and square wave outputs. Sine wave f = 81.69KHz. Sine wave Vpp = 7.76V. Square wave f = 81.76KHz. Square wave Vpp = 11.4V.

Sine wave and square wave outputs.

Oscilloscope displaying AC coupled triangle wave and square wave outputs. Triangle wave f = 81.96KHz. Triangle wave Vpp = 6.96V. Square wave f = 81.83KHz. Square wave Vpp = 11.4V.

Triangle wave and square wave outputs.

Oscilloscope displaying AC coupled triangle wave and square wave outputs. At f = 1.2MHz the triangle peaks are rounded and the square wave aren't square.

Distorted triangle and square wave outputs.

The kit provided build instructions, PCB, all components, and molded case including screws.

This kit need an external 9-12V DC power supply but did not provide it.

With 12V power supply:

  • Square wave output 11.4V (amplitude not adjustable). Duty cycle 50% (not adjustable).
  • Triangle wave output 7.96Vpp before it start clipping. Amplitude adjustable.
  • Sine wave output output 6.96Vpp before it start clipping. Amplitude adjustable.
  • Max frequency 1.2MHz. But at this frequency the square wave doesn’t look square, and the sine and triangle wave are indistinguisable.

Notes:

  • Square wave output is always available (have its own terminal).
  • Triangle and sine wave output share the same output terminal and are switchable using a jumper.
  • The square wave and the triangle/sine wave output are always the same frequency (share the same frequency controls).
  • Amplitude control is reversed (turning the potentiometer clockwise will reduce the triangle/sine wave amplitude). It’s not like I soldered it the wrong way around either, the potentiometer footprint made it impossible.
  • The kit doesn’t provide a way to control the DC offset.
  • It is tiny. Width 5cm, length 6.5cm, and height 3.5cm (including molded case and potentiometers’ knobs).

A fun soldering project 😁