Can someone try to confirm this -- possibly cable reflections might have affected my measurements?? A similar test without TG level compensation and a 50 Ohm terminator at the "free end" of the BNC T already showed soemthing like 263MHz 3dB single channel bandwidth on my DS1054Z, so the result may also well be accurate.
Many thanks, TheoB! Good to see posts from someone who (a) knows what he is doing, and (b) gives a balanced view of the DS1054Z, putting things in perspective, mentioning strengths and limitations without much fanfare.
CH # Sinc Average Risetime 1 On Normal 1.5ns 2 On Normal 2.11ns 2 On Averaged 2.09ns 4 Off Normal 4.61ns 4 On Normal 2.83ns 4 Off Averaged 4.53ns 4 On Averaged 3.34ns
CH # Sinc Average Risetime 1 On Normal 1.5ns 2 On Normal 2.11ns 2 On Averaged 2.09ns 4 Off Normal 4.61ns 4 On Normal 2.83ns 4 Off Averaged 4.53ns 4 On Averaged 3.34ns
From this good table showing effects of sampling rate on bandwidth another thing becomes evident:
Z would be a real kicker if it supported ETS. Because with ETS it would have full analog bw on all channels on repetitive signals. Did not the old models have it? DS1102* 25GSa/s, DS1052* 10GSa/s. Good stuff if you know how to use it
From this good table showing effects of sampling rate on bandwidth another thing becomes evident:
Z would be a real kicker if it supported ETS. Because with ETS it would have full analog bw on all channels on repetitive signals. Did not the old models have it? DS1102* 25GSa/s, DS1052* 10GSa/s. Good stuff if you know how to use it
More expensive scopes might trigger before the digitizer. I think the Rigol does everything in the digital domain.
Adding ETS would help in the case you need accurate timing with four channels. But that's only for risetimes/delays outside of the spec of the scope (7ns!!). So we cannot complain can we?
This data is very interesting, but is this right, memory depth is <= 30 pts?? can confound the readings markedly. Any chance you can repeat it what you did on the link and keep memory depth consistent throughout at the highest the 1054z allows?
QuoteThis data is very interesting, but is this right, memory depth is <= 30 pts?? can confound the readings markedly. Any chance you can repeat it what you did on the link and keep memory depth consistent throughout at the highest the 1054z allows?Yes, that's just the time you see times the sample rate (5ns*12*250M=15 points from left to rigth). I indirectly choose the sample rate by enabling more channels. In vector mode it really looks ok, but that's the interpolation. Has nothing to do with samples measured :-). The two screenshots in my previous shows that more clearly.
The maximum at 5ns is 5 samples per division (1Gs/s) or 60 samples per trace. But averaging helps here.
Thanks Theo, I understand. Do you know or have the published datasheet rise time of your EH 122 Pulse Generator?
Thanks Theo, I understand. Do you know or have the published datasheet rise time of your EH 122 Pulse Generator?
Thanks Theo, I understand. Do you know or have the published datasheet rise time of your EH 122 Pulse Generator?
Even more importantly, does it have the specifications for aberrations?
One reason I have a real sampling oscilloscope is for calibrating my fast transition reference level pulse generators. Without this, a transient response and bandwidth measurement using a fast edge is of questionable accuracy. These measurements of the DS1054Z input bandwidth are not consistent with earlier measurements using a leveled signal generator and probably reflect the poor quality of the signal source.
Anyone else noticed this difference in bandwidth as a function of vertical gain?
QuoteAnyone else noticed this difference in bandwidth as a function of vertical gain?Most likely answer is that the bandwidth is limited as some amplifier is enabled for gain settings <= 200mV
But noticed that Sin(x)/x causes noticeable overshoot.
Uhm, I guess that has been discussed to death elsewhere alreadyand isn't specific to the DS1054Z.
For the available data and input bandwidth
the sin(x)/x interpolation is the most faithful representation the oscilloscope (any oscilloscope) can give you
the sin(x)/x interpolation is the most faithful representation the oscilloscope (any oscilloscope) can give youMost faithful representation is given by excessive sampling rate, either RTS or ETS. Once gain - real data.
Even better: understand the math
he is making a nice video but has no idea what he is yabbering on about.