SCOPE Soft Front Panel

[wang]

Hi,

Does SCOPE soft front panel has continous data mode like test panel on MAX for NI 5112?

I tried immediate trigger source, it did not work.

[DFGray]

The immediate trigger source mode on the soft front panel should work like the continuous mode in the MAX panel.  If you got nothing, you have another problem.  Did you open MAX at least once after installing the 5112?  If not, try it.  Did you try the autosetup on the soft front panel?  There are several ways to get no trace with a 5112 in immediate trigger mode using the soft front panel.  The autosetup should cure them.  If these two things don't take care of you, let us know and give a few more details of your setup.

[wang]

Dear DFGray:

Thank you very much for your help.

I made sure I did not either open MAX at least once or without open. Then I tried the autosetp, it did get any waveform.

So, now I give you more detail. 

If I set my trigger source as edge, rising slope, ch0 , nornal mode, DC couple, 1Mohm impedence, 100MHz bandwidht, X-asix 10 micorsecond/div, normal acquiration type, 40% ref position, y axis was set to ch0, 2V/per div., AC copule, offset 0.

I got 0.51volt, but it did not go back to 0 volt horizontal line after 1 to 2 seconds. I am expecting to get a shock beep pulse waveform

signal like a real oscilloscope. I should get 0.51 volts and then go back to 0 volts after 1 to 2 seconds.

Can you tell me how to get it on soft front panel?

[DFGray]

wang,  you probably have a connection problem.  It sounds like you have a large capacitance and high impedance on the input of the scope (which is high impedance and low capacitance).  Switching to 50Ohm input may help, but may also destroy something.  Find a local electrical engineer to help you wire your circuit.  If there are none, post a picture of your current circuit with all values and someone here may be able to help.  Even a scanned in hand drawing would be fine.

[wang]

Hi,

I tried 50 ohm. It did not work  Here is my diagram?

I am getting the entire waveform in edge trigger mode. But my question is the entire waveform will not go back from 5.1V to 0V after

1 to 2 second. In real tektronix scope, it can. Why? Is soft front panel not like a real oscilloscpe? can someone answer this question

to me directly? Thanks!

I appreicate if you can reply to me promply.

[wang]

Hi,

I tried 50 ohm. It did not work  Here is my diagram?

I am getting the entire waveform in edge trigger mode. But my question is the entire waveform will not go back from 5.1V to 0V after

1 to 2 second. In real tektronix scope, it can. Why? Is soft front panel not like a real oscilloscpe? can someone answer this question

to me directly? Thanks!

I appreicate if you can reply to me promply.

[DFGray]

Your diagram is very fuzzy. Provided the 5112 can handle the voltage, try connecting it directly to your output device using 1MOhm input impedance.  The 5112 can read up to +/-25V.  I cannot read the value of the lower resistor on the page (1kOhm?), but it appears you have a 1000X divider circuit.  Is this true?  Do you need this?  What are the voltages outputs of the device under test?  What is the output impedance of the device under test?

[DFGray]

One more thought.  Are you taking data for a long enough time?  By default, the the soft front panel will give you about 50 microseconds of data (1000 data points at 20MHz).  The 5112 is capable of taking hours of data at the slower repetition rates.  Try increasing the number of samples or the time/division.

[birdhl]

Dear DGGray:

What is the output impendance of the device under test?

Do you mean the impendace of the BNC output jact or the output impendance of the device I am actually measure?

Attached is my diagram. Will that help? Is so, pls tell me the impandance.

Thanks!

[birdhl]

Dear DGGRAY:

Thank you very much!

I am going to provide you much detail.

1) I tried connecting NI5112 directly to function generator. I don't know the input impendacne of my function generator. But it

can provide the ouput waveform on the SPF.

2) My voltage output of my device under test is 5.1V.

3) By default, my SFP will give about 50 microseconds (1000 pts at 20MHz). I have increase the record length to 1000000 and 100MHz. The time division is increased to 40 microsecond/div. It did not work. I don't know where I can change the number of samples. I am glad if you can tell me.

4) I still could not do it like the real oscilloscope. In the real oscilloscope, I can get AC 5.1V and then go back to 0 volts after maybe

   less than 1 second. Can you tell me if SFP behave excatly like a scope directly? I also tried using edge and immediate mode.

   I read the help menu of normal mode. It said normal mode can make a continous waveform. is that right? I want my

   waveform not to just stop and I want it to go back to 0 volt like a real scope and then the line is running continously.

  Why type of trigger should I use? Can you suggest?

  Attached is my diagram to make you clear of what I want to get.