Products > Test Equipment
Siglent 2104XP Lockup on Bode Plot
Ray CI:
Hi Folks...
I can't seem to get Bode plots to work on a new Siglent 2104XP. I have tried all seemingly logical configuration settings. Upon starting the plot, the unit lights flash (while doing the auto-set) then, the scope locks-up indefinitely and must be manually power-cycled.
To simplify the explanation, an example (trivial) LP filter circuit is shown (470Ohm resistor and 1uF cap) connected to the waveform generator set to 1V pp. Channel 1 (probe on the left) is at the input. Channel 3 (probe on the right) is reading the output. Manually energizing the ckt at different frequencies with the AWG indicates the ckt works and the probes are connected properly.
Enclosed are pics of the circuit and all relevant Bode config parameters. The scan is running from 100 to 5kHz. This is my first time using the Bode Analysis feature since getting this scope. I don't see what I'm doing wrong and need some additional eyes on this.
Any thoughts on what might be going wrong here?
PS: Yes, I have read the manual thoroughly (it's basically useless) and I've watched numerous YouTube videos that demonstrate this feature. Still stuck!
EDIT: When setting this up, the "Internal Interface Test" shows successful status.
Thanks
Ray
tautech:
For newbies to Bode plot the simplest mistake is not placing a Tee into the DUT stimulus path to provide a reference signal into the scope.
FG Out should be tee'ed into ch 1 and then to the DUT and the through path into the selected channel provides the info for the scope to plot the result as it sweeps through the set frequency range.
Simply, without providing a reference signal you won't get a result.
Initially I would leave vertical scaling to Auto to be sure to get a result on the display.
This app note for X-E Bode plot might provide some further guidance.
https://siglentna.com/application-note/bode-plot-filter-oscilloscope-generator/
However, do note they are using a standalone AWG and have synced outputs which negates the need to tee the stimulus.
Martin72:
--- Quote ---For newbies to Bode plot the simplest mistake is not placing a Tee into the DUT stimulus path to provide a reference signal into the scope.
--- End quote ---
See picture one...
Plus:
--- Quote ---Upon starting the plot, the unit lights flash (while doing the auto-set) then, the scope locks-up indefinitely and must be manually power-cycled.
--- End quote ---
Me I´ve forgot one or two times to clamp on the source signal, but this never lead the scope to hang.
@Ray:
Do a default setup, then try again...
Ray CI:
--- Quote from: tautech on June 23, 2023, 10:46:32 pm ---For newbies to Bode plot the simplest mistake is not placing a Tee into the DUT stimulus path to provide a reference signal into the scope.
FG Out should be tee'ed into ch 1 and then to the DUT and the through path into the selected channel provides the info for the scope to plot the result as it sweeps through the set frequency range.
Simply, without providing a reference signal you won't get a result.
Initially I would leave vertical scaling to Auto to be sure to get a result on the display.
This app note for X-E Bode plot might provide some further guidance.
https://siglentna.com/application-note/bode-plot-filter-oscilloscope-generator/
However, do note they are using a standalone AWG and have synced outputs which negates the need to tee the stimulus.
--- End quote ---
Thanks tautech... At this stage, I'll try anything. Trust me on this, I've tried multiple circuits and literally dozens (if not a hundred) different config settings. They all just hang the scope. Once it's locked-up, it could sit there for an hour and not recover. All the buttons are frozen and it needs a hard power reset to recover. Is that consistent with not using a Tee? I would think that an improper wiring setup would lead to a weird/inaccurate plot result.
Ray
tautech:
--- Quote from: Ray CI on June 23, 2023, 11:08:10 pm ---
--- Quote from: tautech on June 23, 2023, 10:46:32 pm ---For newbies to Bode plot the simplest mistake is not placing a Tee into the DUT stimulus path to provide a reference signal into the scope.
FG Out should be tee'ed into ch 1 and then to the DUT and the through path into the selected channel provides the info for the scope to plot the result as it sweeps through the set frequency range.
Simply, without providing a reference signal you won't get a result.
Initially I would leave vertical scaling to Auto to be sure to get a result on the display.
This app note for X-E Bode plot might provide some further guidance.
https://siglentna.com/application-note/bode-plot-filter-oscilloscope-generator/
However, do note they are using a standalone AWG and have synced outputs which negates the need to tee the stimulus.
--- End quote ---
Thanks tautech... At this stage, I'll try anything. Trust me on this, I've tried multiple circuits and literally dozens (if not a hundred) different config settings. They all just hang the scope. Once it's locked-up, it could sit there for an hour and not recover. All the buttons are frozen and it needs a hard power reset to recover. Is that consistent with not using a Tee? I would think that an improper wiring setup would lead to a weird/inaccurate plot result.
--- End quote ---
It can't make any sensible plot without a reference waveform, period !
Using the internal FG as you said you where, it must be tee'ed. The scope inputs need the stimulus values/info as the SW only drives the FG....internal connections to FG don't mean shit as far as getting stimulus info back to compute a plot.
It's less about settings and instead hookup as this must be correct.
So dedicate ch1 to the stimulus reference that also goes to the DUT and the result into any of the other channels which need be set to receive the result.
If we consider there must always be a channel needed for the reference (stimulus) waveform there are 3 more in these 4ch DSO's where we can also use 2 to measure points/stages within a DUT and one for the full through result.
Navigation
[0] Message Index
[#] Next page
Go to full version