Excellent, looking forward to some impressions...
And good luck sorting things out!!
Rigol shall [...]
Rigol may [...]
Which model?
...
Your memory is like a fish: I've said many, many, many, many, many times in this thread that the DHO924 ought to turn on the 125Mhz limiter (which it already has internally) when there's more than 2 channels enabled.
There is no scope (including ones from Rigol) that say it is 200 MHz scope and will drop sampling below Nyquist, not mention well below BW frequency....
Solution is to call it 70 MHz scope and say it has 100/200 MHz limited mode... And limit BW when it breaks basic sampling theorem..
And Nico's GW Instek was never released that way, it was after unofficial hack. GW Instek was honest there.
What is wrong with you? DHO900 is a bad design. Why don't you want Rigol to fix it? Why do you want that your fellow Rigol users to buy badly designed scope... You're not helping Rigol..
"bad" design is based on your definition. a good scope must not alias? i think you didnt catch my reply to Warhawk. you cant avoid aliasing. you can feed your pure 70MHz to it and set the time scale large enough so the sample rate will reduced badly, and you get aliasing from your 70MHz.
Which model?I'm aiming at DSLogic U3Pro16, I see no reason to pay extra $100 for 16 additional channels as I doubt I will ever use that many. My MSO has got 16 channels, and I don't remember ever using more than 9 (for 8 bit bus + clock signal). And U3Pro16 has a dedicated clock input, so I won't even have to waste an input for it in abovementioned case.
DHO800 has it at higher (almost 180 MHz) and is also 12 Bit meaning it will alias on signal levels you would not have to worry with 8 bt scope...So... just like many other oscilloscopes.
eg. Siglent SDS1204X-E has it at 230MHz and a 1GHz sample rate with all channels on.
Great minds think alike. DHO942s is canceled, part of the funds is going to the U3Pro16 with additional shielded wires.
There is no scope (including ones from Rigol) that say it is 200 MHz scope and will drop sampling below Nyquist, not mention well below BW frequency....
Solution is to call it 70 MHz scope and say it has 100/200 MHz limited mode... And limit BW when it breaks basic sampling theorem..
And Nico's GW Instek was never released that way, it was after unofficial hack. GW Instek was honest there.
What is wrong with you? DHO900 is a bad design. Why don't you want Rigol to fix it? Why do you want that your fellow Rigol users to buy badly designed scope... You're not helping Rigol.."bad" design is based on your definition. a good scope must not alias? i think you didnt catch my reply to Howardlong. you cant avoid aliasing. you can feed your pure 70MHz to it and set the time scale large enough so the sample rate will reduced badly, and you get aliasing from your 70MHz. trying to add auto attenuation, will probably complicate the front end or FPGA logic cells hence increase cost... and it would not avoid confusion anyway... for the rest of us, we would like Rigol to fully open the front end BW to 1.25GSa/s divide 2.5X = 500MHz (or maybe 250MHz for 2 channels probing at 625MSa/s) like the old high end Tek/HP DSO... and later limit it ourself internally or external circuit if we need to. real circuit is not just viewing pure sine wave, there are other things like verifying risetime, gate capacitance and signal integrity on digital signal, that will not cause aliasing. if Rigol fullfill your theoritical utopia desire, then we will call it bad/crippled design, they wont be able to satisfy everybody. because this is subjective, as people call it horses for courses.
.. real circuit is not just viewing pure sine wave, there are other things like verifying risetime, gate capacitance and signal integrity on digital signal, that will not cause aliasing.
It is BAD design. It is only scope that cannot satisfy (and by factor 3x less than needed) Nyquist including Hanteks, UNI-T, Owon and all other scopes that are even cheaper.
For the avoidance of doubt, for PC based LAs I use both the Analog Discovery and the Digital Discovery extensively: while the AD in particular is often deemed a "hobbyist" tool, in practice I wouldn't be without it. Both are worthy of bench positions, or, more accurately, worthy of hand baggage inclusion for field work - in fact I have three ADs for exactly this reason!That explains a lot. Take a look at DSLogic U3Pro https://www.dreamsourcelab.com/product/dslogic-series/ This is a good example of what modern PC-based LA can do. And that is only using USB3 5Gbps, so with 10 Gbps you can double all numbers.
It is BAD design. It is only scope that cannot satisfy (and by factor 3x less than needed) Nyquist including Hanteks, UNI-T, Owon and all other scopes that are even cheaper.
Yeah, yeah.
What If I'm into HAM radio and Arduinos?
I get a 200Mhz, 2-channel scope for my radio work and a 4 channel 'scope for Arduino work.
It's not BAD design. You really think they don't know about it and made a mistake? It's a deliberate design/marketing choice.
What If I'm into HAM radio and Arduinos?
I get a 200Mhz, 2-channel scope for my radio work and a 4 channel 'scope for Arduino work.
It's not BAD design. You really think they don't know about it and made a mistake? It's a deliberate design/marketing choice.
real circuit is not just viewing pure sine wave, there are other things like verifying risetime, gate capacitance and signal integrity on digital signal, that will not cause aliasing.
the problem is, he is not HAM
It is BAD design. It is only scope that cannot satisfy (and by factor 3x less than needed) Nyquist including Hanteks, UNI-T, Owon and all other scopes that are even cheaper.
What makes you think you can trust the rise time measurement in the presence of aliasing?
What If I'm into HAM radio and Arduinos?
I get a 200Mhz, 2-channel scope for my radio work and a 4 channel 'scope for Arduino work.
It's not BAD design. You really think they don't know about it and made a mistake? It's a deliberate design/marketing choice.the problem is, he is not HAM, so i think its wise to make this thread non-repetitive, otherwise aliasing will occur. here attached of Leo Bodnar pulse, i wish to see shorter rise time, no aliasing guaranteed!
the problem is, he is not HAM
Not necessarily "HAM" but anything where you want to connect some coax and have maximum possible bandwidth.It is BAD design. It is only scope that cannot satisfy (and by factor 3x less than needed) Nyquist including Hanteks, UNI-T, Owon and all other scopes that are even cheaper.
As noted earlier: I can make your favorite oscilloscope alias with a 1kHz sine wave. All I have to do is fiddle with the settings.
(nb. I've actually done this...)
If I suspect a signal is aliasing on my DHO900? I can turn a channel or two off and look at the signal with 500Mhz or 1Ghz sample rate. It only takes a second. If the frequency jumps around then, yep, it was aliasing.
I'm talking (and I said many many times) about DHO900.
I said DHO800 will work fine...
What makes you think you can trust the rise time measurement in the presence of aliasing?Simple: He only has one channel enabled!
DHO800 has it at higher (almost 180 MHz) and is also 12 Bit meaning it will alias on signal levels you would not have to worry with 8 bt scope...So... just like many other oscilloscopes.
eg. Siglent SDS1204X-E has it at 230MHz and a 1GHz sample rate with all channels on....i remember there is called hi-res capture, or ETS? to avoid such aliasing, i need to power up DHO804 again if i can find workaround...