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+VoltLog It's crazy what you can get for the money these days. Wasn't that many years ago that a 2MHz sine/square/triangle function gen was the entry level standard.

+VoltLog may be increase in sales making companies produce stuff at bulk and and lower costs. a lot of hobbyists buying decent equips these days.

there might be more factors to this, like for example R&D might be cheaper for these smaller companies, they don't design custom asics, they use off the shelve parts and they don't exactly use top of the line components in the hardware. Shaving a few dolars here and there coupled with a lower profit margin might be the reason the end equipment is cheaper.

why is it that you can't compare the two channels if the voltages are different?

TheRealMoomin it’s not comparing the two channels, it’s comparing the output of two different instruments. One Rigol and one Siglent. The problem of that comparison is that Siglent is driving twice as much output swing than Rigol at the expense of larger distortion. So if one really want to compare distortion accurately, the output drive level need to me the same.

@@Wooksterish A higher amplitude requires a faster rise time. For a certain signal A*cos(omega*t) you can find the slope with -A*omega*sin(omega*t). I.e. increasing the amplitude or the frequency causes an increase in maximum signal slope. As you can imagine, it is harder to drive reactive loads with a higher slope. So things like cable capacitance will ruin your day sooner! So yeah, Digger D is right, you should compare apples to apples between the two devices, and have the exact same waveform specs to compare, especially important at the higher frequencies.

+Mr Carlson's Lab It even looks like only 4-5 bits resolution on that staircase.

+Alfred Stampe Not a matter of limited resolution but limited memory, I believe. The whole cycle is stored in the limited memory which leads to a low sampling rate and finally results in the stair case.

+NPNtube Rigol: There must be a minimum number of stairs to have a defined ramp. I count a bit more than 32 stairs, maybe exact 32 stairs from 10% to 90%. 10Hz vs. 195µs ramp time vs 32 stairs lead to 16384 samples memory depth which matches the specification of the device. Siglent on the other hand specifies 8M samples... huge difference.

And she's buying the stair way, to heaven.

+Andy Lawrence Yeah, small gear is nice. Gone are the days of huge gear hogging your whole bench.

+EEVblog that´s why i saved my money and bought a DSO, back when they cross the 500 bucks line...and i still need no newer one, as all i need is somewhere below 10MHz, mainly audio-frequencies...Thanx modern technology to let us buy these things, and also to let us buy old things relatievely cheap....:) And thanx to You, Dave, to put a light on these things!!!

+lmiddleman It's called "digit grouping" and it is not uncommon, because it makes reading big numbers more easy. You can disable it on the Rigol (and also exchange dot and comma as decimal and group separators). Interesting Wikipedia article: en.wikipedia.org/wiki/Decimal_mark

+Jo Pe It is a shame that we all could not have cone to a common agreement on how to specify decimals and digit groupings in a single universal format for everyone. It makes internationalization very confusing when 3,100.099 and 3.100,099 mean both the same value and simultaneously a very different value, either of which may be the correct value.

Some people reccomend 5 times bandwidth for square waves. uC runs from square wave clock its bandwid is also depended on the rise time.

Your uC might run at 80mhz, but that is the internal clock. You will notice with most uCs the maximum output frequency you can achieve is about 2-3Mhz. What Alperen says is true, square waves look the way they do because they posses higher frequency content beyond their base frequency, and thus you need a higher bandwidth to display them properly. So a 15Mhz scope would more than suffice, which is practically any scope nowadays. About the doubling of bandwidth, I think you are confused by the Nyquist criterium. It dictates that your SAMPLING frequency should be at least twice the MEASURED frequency. This is a digital phenomena due to sampling. The 'bandwidth' on the oscilloscope though, is not from digitizing. It is instead an analog bandwidth. I.e. with a 100mhz scope you can measure at most a 100mhz pure sine wave (usually scopes do better than their quoted analog bandwidth though). On this note, scopes also often quote a sample rate, for example 1Gs/s. That means that their sample frequency is 1Ghz. This is the frequency that matters for the above nyquist criterium. But for any modern well designed scope, this sample rate is far above the analog bandwidth, even in worst case scenarios.

nvm, decided to splurge on the SDG2122x XD

+lmiddleman It would make more sense for the maximum delay to be two periods.

I was assuming it was plus or minus 100ms.

lmiddleman Negative delay? So this is how they make time machines...

+lmiddleman I think Dave misread, 100.000,000 is 100K in "European" style decimal separators

+Brandon Pais en.wikipedia.org/wiki/Window_function#Blackman_windows

Please don't! Don't let the UI cancer swap into electronic test equipment!

+Joop Terwijn Hopefully Dave remembers to roll out the red ESD mat.

+Gahlan Aventis It is either incredibly time consuming, or very expensive to do this for long technical videos.

+EEVblog Plus, Dave is really easy to understand even for non-native speakers. I happen to be an expert on this subject being a non-native speaker myself.