Cheap bode plotter.

[50AE]

Hi folks,

What could be the cheapest device for bode plotting in the audio range? It doesn't have to be an oscilloscope, although most devices are. I laid my eyes on the Velleman PCSU 200 first.

P.S. A simple sound card won't be enough, because I need the 200-300kHz range.

Thanks,
Alexander.

 

[jan.didden]

This will do everything you can think of:

USB Oscilloscope and Logic Analyzer - Digilent Analog Discovery 2

Including a Bode plotter. It's a lab in a box.

Jan

 

[50AE]

Thank Jan. I know of it and have used it, but sadly it breaks the bank.

 

[tvrgeek]

300KHz? You said audio. Audio of what 😀

Some IO boxes can sample at 192K. Not sure if Holm or Arta can use that though. Focusrite Scarlett 2i2 V3 for example. About $150 over here. No idea in your market. To get above that, you are going into the instrumentation world and zeros add to the price real quick.

 

[50AE]

Hi there,

It's important to see at least 150kHz above the audio band, as a transformer manufacturer, I want to be able to see what happens outside the audio band.

But you gave me a hint on cheap 384kHz sample rate DACs.

 

[50AE]

Hi Folks,

Two months since, I'm a happy owner of the Velleman PCSU200! Extremely happy with this small toy! The graphic interface is quite intuitive and quick to learn.

There are "output normalization" by input and averaging options, which are quite helpful. There's also quite enough of steps for measurement resolution, more than 30 per decade.

Bode plotting range can be done from a maximum range of 10Hz to 100kHz, or 1kHz to 1MHz for thourough HF testing.

Here are some bode plots of random transformers!

 

[jan.didden]

Looks nice! Do you know the vertical resolution, # of bits? It's not in the specs ...

Edit - found it. 8 bits.

Jan

 

[50AE]

Not really Jan, haven't studied this. However the tiny ripples you can see on the bode plots are random noise.