Demonstration video about the visualization techniques, including the new ultra-acquire mode:
-snip
Much appreciated if someone could run the Two-Tone IMD at 100KHz, 1MHz & 10MHz to show the input channel linearity?
Best,
Do you really want to ignite another discussion about measuring distortion with DSOs ?
Jokes apart, I guess it would be necessary a quite high quality generator to discern DUT IMD from source IMD.
Do you really want to ignite another discussion about measuring distortion with DSOs ?
Jokes apart, I guess it would be necessary a quite high quality generator to discern DUT IMD from source IMD.
Oscilloscope inputs have poor linearity so the demands on the two-tone signal source are not great.
Do you really want to ignite another discussion about measuring distortion with DSOs ?
Jokes apart, I guess it would be necessary a quite high quality generator to discern DUT IMD from source IMD.
Oscilloscope inputs have poor linearity so the demands on the two-tone signal source are not great.
Ok, define "not great" with a number.
Do you really want to ignite another discussion about measuring distortion with DSOs ?
Jokes apart, I guess it would be necessary a quite high quality generator to discern DUT IMD from source IMD.
Oscilloscope inputs have poor linearity so the demands on the two-tone signal source are not great.
Ok, define "not great" with a number.
8 bits is roughly 51 dB SFDR and the analog front end linearity is unlikely to be even that good. Good linearity is a tough problem in this case.
Do you really want to ignite another discussion about measuring distortion with DSOs ?
Jokes apart, I guess it would be necessary a quite high quality generator to discern DUT IMD from source IMD.
Oscilloscope inputs have poor linearity so the demands on the two-tone signal source are not great.
Ok, define "not great" with a number.
8 bits is roughly 51 dB SFDR and the analog front end linearity is unlikely to be even that good. Good linearity is a tough problem in this case.
Do you really want to ignite another discussion about measuring distortion with DSOs ?
Jokes apart, I guess it would be necessary a quite high quality generator to discern DUT IMD from source IMD.
Oscilloscope inputs have poor linearity so the demands on the two-tone signal source are not great.
Ok, define "not great" with a number.
8 bits is roughly 51 dB SFDR and the analog front end linearity is unlikely to be even that good. Good linearity is a tough problem in this case.
Most modern quality AWGs will likely fit well within that range, since they originate the signal from 14~16 bit DACs and have decent buffer & scaling amplifiers. Some even support digital waveform combining within the instrument, at least our experience with the SDG2000X/6000X demonstrated this as an effective means of signal waveform addition/combining without significant linearity issues.
Best
Do you really want to ignite another discussion about measuring distortion with DSOs ?
Jokes apart, I guess it would be necessary a quite high quality generator to discern DUT IMD from source IMD.
Oscilloscope inputs have poor linearity so the demands on the two-tone signal source are not great.
Ok, define "not great" with a number.
8 bits is roughly 51 dB SFDR and the analog front end linearity is unlikely to be even that good. Good linearity is a tough problem in this case.
Most modern quality AWGs will likely fit well within that range, since they originate the signal from 14~16 bit DACs and have decent buffer & scaling amplifiers. Some even support digital waveform combining within the instrument, at least our experience with the SDG2000X/6000X demonstrated this as an effective means of signal waveform addition/combining without significant linearity issues.
Best
I too own an SDG2042X and I'm aware it's now capable to internally combine channels but we have no specs about intrinsic IMD, so I do not see a lot of sense to source my scope with it and declare that everything "wrong" that I see is from the DSO, IMHO it would be necessary a signal generator with proved IMD specifications data.
8 bits is roughly 51 dB SFDR and the analog front end linearity is unlikely to be even that good. Good linearity is a tough problem in this case.
Why do you mention 8 bits ?
Do you really want to ignite another discussion about measuring distortion with DSOs ?
Jokes apart, I guess it would be necessary a quite high quality generator to discern DUT IMD from source IMD.
Oscilloscope inputs have poor linearity so the demands on the two-tone signal source are not great.
Ok, define "not great" with a number.
8 bits is roughly 51 dB SFDR and the analog front end linearity is unlikely to be even that good. Good linearity is a tough problem in this case.
Most modern quality AWGs will likely fit well within that range, since they originate the signal from 14~16 bit DACs and have decent buffer & scaling amplifiers. Some even support digital waveform combining within the instrument, at least our experience with the SDG2000X/6000X demonstrated this as an effective means of signal waveform addition/combining without significant linearity issues.
Best
I too own an SDG2042X and I'm aware it's now capable to internally combine channels but we have no specs about intrinsic IMD, so I do not see a lot of sense to source my scope with it and declare that everything "wrong" that I see is from the DSO, IMHO it would be necessary a signal generator with proved IMD specifications data.
It was tested and documented here on EEVBLOG...
8 bits is roughly 51 dB SFDR and the analog front end linearity is unlikely to be even that good. Good linearity is a tough problem in this case.
Why do you mention 8 bits ?
Because if the input signal conditioning has great difficulty achieving 8 bits of linearity, then 12 bits is much harder even than that. This is one of the reasons that 8 bits has been considered largely sufficient for DSOs.
It was tested and documented here on EEVBLOG...
What do you mean, maybe that now SDG2KX have official IMD numbers for channels combine function valid for entire frequency ranges ?
It was tested and documented here on EEVBLOG...
What do you mean, maybe that now SDG2KX have official IMD numbers for channels combine function valid for entire frequency ranges ?
All joking aside, do your homework as suggested
Best
Sorry but I miss the point, here we have a 12 bits scope and a request for a dual tones IMD test, my point was that without a signal source with a known IMD specification is not possible to proceed to test the DSO under that aspect.
Do you mean that is useless test ?
The signal source just has to be better than the possible performance of the DSO, but I have seen the transient response of "12 bit" DSOs, and none of them have 12 bit analog or noise performance.
The signal source just has to be better than the possible performance of the DSO, but I have seen the transient response of "12 bit" DSOs, and none of them have 12 bit analog or noise performance.
Seems to me like you're asking the wrong questions.
The question is: Are they better than "8 bit" DSOs. In the case of these Rigols the answer seems to be a resounding "yes!"
They are better than the 8 bit Rigols, but *not* better than all older 8 bit DSOs or even analog oscilloscopes.
so does this make the siglent sds2000 plus a better overall / all round scope at the same price then?
The signal source just has to be better than the possible performance of the DSO, but I have seen the transient response of "12 bit" DSOs, and none of them have 12 bit analog or noise performance.
Seems to me like you're asking the wrong questions.
The question is: Are they better than "8 bit" DSOs. In the case of these Rigols the answer seems to be a resounding "yes!"
They are better than the 8 bit Rigols, but *not* better than all older 8 bit DSOs or even analog oscilloscopes. The 8 bit Rigols are particularly bad, so it is not difficult to improve on their performance.
Where the 12 bit DSOs do always perform better is FFT dynamic range; low RBW (resolution bandwidth) from a large FFT size minimizes the contribution from front end noise so performance is limited by quantization noise, although that does nothing to improve the SFDR which depends on the linearity.
This new Rigol 12bits line has nothing to do with previous ones under a lot of aspects, input noise and scope responsiveness are the first two things that you notice at first glance.
so does this make the siglent sds2000 plus a better overall / all round scope at the same price then?