Hello, I have a PCSU200 and works fine.
Is it possible to see the value of the Oscilloscope Trigger Level, just like the Vpp-textfield under the FunctionGenerator Amplitude?
If not, could that be a good upgrade option?
Possibly activating under PullDownMenu/Options/TriggerOptions/NoiseReject?
Thanks.
Thank you for the feedback. The feature you suggested would be very useful indeed.
Now this feature is implemented in the PcLab200 software.
The value of the trigger level is displayed.
I think there is no ‘harm’ to display the value continuously without the activating menu option.
Here is the link to download the ‘pre-release’ version of the software for evaluation:
app.box.com/s/q3lqir9d8eo3m2rq73z7
Thanks for considering the option and implementing it so fast.
I installed the evaluation version without the hardware because I’m abroad.
I could now see that 0V is not in the center of the slider that apparently now moves from -5,19V to +2,72V.
Is there a reason that the upper value can’t reach +5V?
Can’t wait to test it when I’m home again within 8 days.
Then I will send feedback on this feature.
[quote]I could now see that 0V is not in the center of the slider that apparently now moves from -5,19V to +2,72V.-
Is there a reason that the upper value can’t reach +5V?[/quote] Yes there is. - The trigger level is using the ground level of the selected trigger source channel CH1 or CH2 as a reference.
The small blue ‘1’ on the left side of the screen indicates the ground reference level of CH1 and the red ‘2’ of CH2.
If you move both of the traces to the middle of the screen, then 0V is in the center of the trigger level slider.
I checked ground level of the selected trigger source channel CH1 or CH2 as a reference and worked ok.
I checked the TriggerLevel set on 1.00V for both DC and AC coupling.
a) With DC-coupling the trigger worked 1.53Vpp and 0.54VRMS.
b) With AC-coupling the trigger worked 1.94Vpp and 0.69VRMS.
So, is the TriggerLevel looking at twice VRMS (2x0,54=1,08V) at DC-coupling,
…and roughly half Vpp (1/2x1,94=0,97V) at AC-coupling?
In both cases you had 1V set as trigger level.
In both cases the ‘absolute’ trigger level is 1V.
The triggering is activated when the signal amplitude reaches this level.
Using the AC coupling you get more ‘real’ result.
Should be half Vpp using the AC coupling and also using the DC coupling.
I try to clarify:
There is a little DC offset at the generator output.
This positive DC offset is displayed on the oscilloscope screen by using the DC coupling only.
You can see the waveform is positioned a little ‘higher’ on the screen when DC coupling is used.
This is the reason to different Vpp signal values who activate the triggering using DC and AC coupling.
The triggering is activated when the sum of the AC component and the DC component of the signal crosses 1V level.
You may continue to check the lowest triggering point (around -1V) in both cases.
The difference between the negative peak trigger point and the positive peak trigger point should be 2V when 2Vpp waveform is used.
You may use fixed 2Vpp signal and then check the lowest and highest trigger level for it.
The difference between these trigger level values should be 2V.
I checked everything you have said and was correctly working.
Than why was my AC-coupling_Trigger screendump not at 2.00Vpp?!
I found that reason myself:
The label “Running/WaitingForTrigger” (at the right of the label “TriggerLevel value”) was still set as WaitingForTrigger, so it was not triggered yet!
This because the label has a time delay for switching between text!
For a more visual distinguished view I also switched between generator Sine and Tri that has direct results on the screen!
So, for AC-coupling everything is working as aspected, where the possitioning is done by AutoSet.
But for DC-coupling the DC-offset can not be possitioned around the zero!
Is it therefore not an option that when the coupling is manually set on DC, the AutoSet will not switch back to AC?
This enables the possibility to also Autoset DC-coupling around the zero!?
[quote]Is it therefore not an option that when the coupling is manually set on DC, the AutoSet will not switch back to AC?[/quote]I’m sorry, there is no such option.
The Autoset is made to find the best Time/Div and Volts/Div settings to display the waveform on the screen.
The Autoset ‘isolates’ the AC component of the waveform to find out its frequency to make the decision for the best Time/Div setting.
This is why AC coupling is used while Autoset is selected.
Here a snippet from the Help file:
Autoset
Automatic setup for the Volts/div, Time/div, and Trigger level to produce a stable waveform of usable size. The trigger will be set on if the wave aplitude on the screen is more than 0.5 divisions.
The signal should be repetitive for proper autoset function: Amplitude 5mV to 30V; frequency above 50Hz; duty cycle greater than 10%.
Ok, thanks for your DC-autoset reply.
I also tested the trigger level for DC waves (wave on top of a dc voltage)…
Generator set on 5KHz at 4.00Vpp, the oscilloscope triggered at a value of 0.23V?!
The generator graphic values are not the same as the oscilloscope graphic values at all.
My digital voltage meter at generator output points to 0.24Volts. So apparently the generator has a low output voltage.
When increasing generator amplitude the oscilloscope first rises and then returns to previous low value.
What’s wrong?
[quote]What’s wrong?[/quote]Nothing wrong.
The function generator of the PCSU200 doesn’t output DC voltage.
Only the AC component of the library waveform is output.
The generator automatically ‘centers’ the AC component of the waveform so that DC component is about zero.
The AC component of your generated library waveform is Vpp = (0.99-0.95)/2 * 4Vpp = 0.08Vpp.
Thanks for implementing the trigger level value that works fine for me.
Will this option be available in all new versions of the software?
