To measure distortion, you can use a notch filter to "cut" the first harmonic.For distortion measurements, I use a Picotech 4262 DSO, as this provides 96 dB dynamic range already without any tricks.This scope is confused by a bandwidth of only 5 MHz.
A 5000 series picoscope with switchable vertical resolution ADC is not suitable for this purpose?
Should be more than enough when measuring distortions in music-range up to 20khz.It turns out that one device is needed to measure distortion, and to see, for example, the self-excitation of an electronic circuit at tens of megahertz, another device is needed ...
Hi blurpy!
I've looked at the QuantAsylum QA401 before, but other forums have had problems with software compatibility (Windows). Meanwhile, the Q401 has been discontinued and replaced with the Q402 as a new product, but production is stalling. I am looking for a reliable solution at an affordable price.
What is your experience with the Q402?
Regards Garga
Hi blurpy!
I've looked at the QuantAsylum QA401 before, but other forums have had problems with software compatibility (Windows). Meanwhile, the Q401 has been discontinued and replaced with the Q402 as a new product, but production is stalling. I am looking for a reliable solution at an affordable price.
What is your experience with the Q402?
Regards Garga
Maybe you are thinking of QA400? They used some parts in that one that modern Windows does not have drivers for. This is as far as I know not an issue with QA401 or QA402. I don't have any experience with Windows myself and use both of them from Linux only.
The QA401 didn't have a user interface for Linux so I made a web interface for it: https://github.com/blurpy/qa401w
And the software for QA402 has official Linux support with a UI, but since it's very new it crashes a lot, so I maintain a web interface for that as well: https://github.com/blurpy/qa40xw
I've done a comparison of how they perform, which you can see here: https://forum.quantasylum.com/t/effect-of-attenuation-level-on-results/494/12
Having spent a lot of time with these devices, I think they are really nice for the price, and I use them a lot. The QA402 needs refinement in the software, but that looks to be improving. The plug and play part is what I like the most, as I've messed around with sound card measurements before and it's a lot of hassle dealing with attenuation and keeping the signal from being messed up by the OS or other software.
You are right that QuantAsylum is struggling with parts delivery, like many others.
Maybe send them a message and ask about it?
5000 is good enough to service and check on audio equipment for musicians (PA, instrument amplifiers). You just cannot measure very low distortion. Probably good enough for normal musical equipment. It is just that 4262 is order of magnitude better.
Pico4262: SFDR 96 dB typical @ 10 kHz, –1 dBfs input
Pico5000: SFDR 14 to 16-bit modes: 70 dB at 100 kHz full scale input.
Having made a logic probe for the SDS2000 (Big thanks to oz2cpu), I was surprised to not find such an important item as setting the trigger hysteresis in the digital channels menu. Without the possibility of triggering hysteresis, the edges of the pulses have random jitter and phantom spurs even at low frequency signals. As a result, time measurements become meaningless when using a logic analyzer. And how did the Siglent's engineers miss such an important point?
Seems that music perception is more complex than the added abilities to recognize certain sinus frequencies with conscious hearing.