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Products => Test Equipment => Topic started by: BillyO on September 07, 2022, 03:20:47 pm

Title: Siglent SDS1104X-E + SDG1032X Bode plot BS
Post by: BillyO on September 07, 2022, 03:20:47 pm

Both the scope and the SDG have been improved using "updated" license keys.

Here is a BODE plot of a simple high-pass RC filter.  Yes, I have tried other resistos and capacitors (of various types).  The exact same issue occurs.

Note the absolute whacko response below 150Hz, then it sorta settles down until 4KHz where it again just flips out.

Anyone else have this wonderful experience?

The scope FW is 6.1.37R8, the AWG is 1.01.01.33R1B6

Title: Re: Siglent SDS1104X-E + SDG1032X Bode plot BS
Post by: nctnico on September 07, 2022, 04:06:09 pm

Look at the signal level... there isn't enough amplitude to measure the phase. So your phase response will be allover the place. This will happen with any instrument that can show phase information.

Title: Re: Siglent SDS1104X-E + SDG1032X Bode plot BS
Post by: BillyO on September 07, 2022, 05:06:00 pm

Problem resolved.

It turned out to be a slightly bent probe tip not allowing the hook to snap on properly.

Took off the hook, straightened the tip, put the hook back on and ..

Everything is fine.  Thanks nctnico, your post started me on the road to figuring it out.  I had been monitoring the filter output with another scope and the signal coming out should have been fine, and sure enough it was.