1
\$\begingroup\$

I'm unable to get the Bode plot to work with this Wien bridge oscillator circuit.

Is there something wrong with my configuration, or does the Bode plot not work without an external signal source?

I assume that the Bode plotter would theoretically measure the frequency response of the oscillator since it produces a signal.

Wien Bridge Oscillator simulation in NI Multisim

New contributor
JOVIN SAN ANDRES is a new contributor to this site. Take care in asking for clarification, commenting, and answering. Check out our Code of Conduct.
\$\endgroup\$
3
  • 1
    \$\begingroup\$ An oscillator doesn't have a valid external signal input hence, a bode plot is meaningless \$\endgroup\$
    – Andy aka
    Mar 19 at 11:19
  • \$\begingroup\$ @Andyaka thank you for your reply. That is what I also thinking lately, I was just looking for confirmation in the internet, and I can't find any. Thank you for confirming it! \$\endgroup\$
    – JOVIN SAN ANDRES
    Mar 19 at 13:51
  • \$\begingroup\$ As another view: A working oscillator has a pole on the imag. axis of the s-plane. This is identical with a pole-Q of infinite - corresponding to an infinite gain at the frequency of oscillation. This cannot give any meaningful result. However, when simulating the LOOP GAIN and display it as a Bode plot you can verify the oscillation criterion. \$\endgroup\$
    – LvW
    Mar 19 at 14:20

1 Answer 1

Reset to default
0
\$\begingroup\$

The original of the very old (BC107) schematic is in Google. You copied the resistance of R4 wrong. The highpass/lowpass Wien Bridge has a bandpass at 1kHz. In google they were at www.next.com, www.electroninic.com and www.blopspot.comm and probably at many more websites.

Wien

Here is the bandpass response:

bandpass response

\$\endgroup\$
2
  • \$\begingroup\$ Audioguru - Hi, In order for you to comply with this site rule, please edit your answer to add a proper reference, which names the source & includes a link back to the original web page / PDF file etc. for the "very old" schematic which you included. (Saying that it is "in Google" is not enough.) Thanks. (After you have done that, please reply in a comment so that I can remove this comment.) \$\endgroup\$
    – SamGibson ♦
    Mar 19 at 16:27
  • \$\begingroup\$ Audioguru - Thanks for editing the answer. However as I said (and as explained in that site rule), the requirement when including material copied from elsewhere, is to provide a link to the source web page, not various website home pages. Therefore to comply with that rule, please provide the specific web page which was the source for that schematic you copied. Thanks. \$\endgroup\$
    – SamGibson ♦
    Mar 19 at 20:24

Your Answer

JOVIN SAN ANDRES is a new contributor. Be nice, and check out our Code of Conduct.

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.