measure the operating frequency of a DC-Dc converter

[origami]

how do you measure operating freqency

I am trying to measure the operating frequency of a DC-Dc converter, I do not have access to the internal circuitry of the converter, I can only measure the input and output pins. Is there a way for me to do this? Is the frequency of the ripple the same as the operating frequency of the converter? Thanks!

Please let me know if I am posting in the wrong section of the forum.

 

[flatulent]

If the rectification is full wave or bridge the ripple is twice the operating frequency. Another trick is to make a multi-turn coil and detect leaked magnetic fields from the internal transformer. You can use an oscilloscope to look at the pickup coil output.