I thought it might be beneficial to compare different probes on the 200MHz SDS1202X-E just to give you an idea what can be expected. I have noticed some folks might be wondering how good the original Siglent probes are and if some other (maybe also more expensive) probes would provide better results, i.e. (some early time there was more differences if I remember right in SDS2k (notX)). But also, this guaranteed speed what do not miss any single trig is not far away from max average speed today with these bit more mature FW's. Side text is finnish but in table there is finchinglish. Not for SDS10004X-E For 2 channel model (note FW) it can find here. I have done it for some previous models including SDS1002X-E. (All t/divs with max segment amount.) If it pass every time without any sigle fail, this is guaranteed maximum speed - minimum trusted trigger period time. Go slowly back to slower speed until it start capture full burst. And repeat until it can not anymore capture every 80000 segment from one burst. If scope can capture every pulse it can this speed. Set burst n=80000 Set segments n=80000 Set generator example for 400kHz (0r period 2.5µs) Set scope for normal trig and sequence mode on. If scope have max amount of frames example 80000 with some t/div. (guaranteed max speed) It can do using pulse generato and burst. One thing is speed what it can use without missing any trigger. (how much time some amount of segments aka "frames". Consequently, with a 2.5-times oversampling (125MHz to 25MHz) the output looks still reasonable (but not stellar, as the sine distortion tests have shown), but any higher, the lack of a proper reconstruction filter becomes just too In sequence mode if I understand right you show average max sapeed. Nothing even close to the required brick-wall filter. Also look at the noise plot up to 200MHz – barely 6dB amplitude drop at the nyquist frequency of 62.5MHz. You bet your bottom dollar there is none, otherwise we would not be able to see so little amplitude drop at 1.6 times the maximum sine output frequency. For a signal generator on the other hand, we need a real filter, i.e. But there we have some digital signal processing that can calculate the best possible filter for the data available. You don’t want to know what it looks like at 50MHz output frequency, sure you don’t! It is only natural, as it is basically the same reconstruction problem as in the scope. It is only 18dB below the carrier and also in the time domain we can see really awful things going on. At 40MHz it looks really bad already: SDS1104X-E_Sine_P10_Play_4MHz_FFT This time I did not even try to measure the harmonics, but used the strongest spur at 85MHz instead. level of just -25dBc… You will not be surprised to see how matters get worse if we go even higher in frequency. Then there is also that nasty spur emerging at 95MHz with an approx. Here is an example for just 30MHz: SDS1104X-E_Sine_P10_Play_3MHz_FFT Yes, the harmonics are even lower at -40dBc, but you should also be able to see the upcoming jitter even in the screenshot. But as I have stated in the review, we don’t get a clean signal anymore above 25MHz. Of course the SAG1021 can output much higher frequencies at slightly reduced amplitude as has already been demonstrated for the noise “waveform”. Well, you were asking for it … now fasten your seat belts.
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