How to turn Computer Sound Card into a Scope

[Nen'O]

Anyone here can advice how to setup computer with software and soundcard into Scope for biasing JFET on mic.

I have sound card with I/O and this free software seems to do the job
https://digilent.com/shop/software/digilent-waveforms/
Thanks

 

[rock soderstrom]

I use it too.

 

[Nen'O]

I use it too.

Great!
How did you set it up?

 

[rock soderstrom]

I use it with a Steinberg UR22 MKII interface.

In this thread are some infomation about Waveforms.

https://groupdiy.com/threads/i-need-a-new-oscilloscope-300€.77401/post-985944

 

[trobbins]

If that software can't easily generate and show returned signals, along with harmonics and harmonic % levels, as a way to assess your bias, then another alternative is REW. Such software may require you to disable all other audio interfaces, and for the software to recognise your soundcard and at least allow a JAVA driver to be selected but better to use an ASIO driver.

 

[Tubetec]

I finally managed to get myself a really good example of a Tek 2215 scope,
Id like to have it so when I hook up the probe Im feeding a signal to the scope , the multimeter and REW via an ADC , I was hoping the scope itself had a buffered output ,but it doesnt ,only 2 inputs.

Both the probes are passive 10:1 , how do I set things up how I like without causing loading of the front end measurement circuits ? The ADC wont be able to cope with the same voltages as the scope or multimeter at its input , how do I protect/attenuate the input to the sound card from high voltage DC or large AC voltage swings yet get best performance for for noise measurement . Should I be thinking of an active probe of some sort , then do the split after that ? I did see a nice cathode follower probe set made by Tek ,but dating from way back .

Might make a good mic head amp directly off the capsule . Nice build quality . Comes with its own attenuator/psu . I wonder what tube they use in there .