Ultra low distortion audio range fixed frequency sine oscillator assembled and tested PCB for distortion measurement applications. The fully analog schematic based on the OPA1656 opamp. Variable output voltage is provided by the automatic gain control circuit. Require single isolated DC 35V external power supply. For the ultra low distortions measuring the board must be shielded. Improved version (6-th step) of this oscillator is in production now.
The 1kHz and the 10kHz boards are mainly in production, but also other frequency boards are available by request.
The harmonic levels (mainly 2nd and 3rd) of the 1kHz board typically are at -155dB...-160dB region .
The harmonic levels of the 10kHz board typically not exceed -145dB, when the load at the output is around 5kohm. When the load is 600ohm, the harmonics rise for app. 15dB.

Specifications:

1kHz oscillator harmonic levels < -150dB
10kHz oscillator harmonic levels < -125dB
Output frequency nominal +/- 1%
Output voltage without load 300mV - 2.7V (RMS)
Output impedance 100ohm
External DC power supply 35V / 25mA
Dimensions (W x D x H) 60mm x 70mm (50mm - board) x 27mm
Weight 20g