why my mso5000 just have only 4GSa/s ?

[zhang011101]

HI, I just save a heart beat wave as .csv file under 8GSa/s using my mso5000, but when I import it to my matlab ,after caculate ,I find it just only have 4gsa/s (in my screen the time span of the waveform is 100us,but the  .csv file of the waveform only have 400000 point), I dont know why , is my mso5000 a fake 8GSa/s osscilloscope ?

[thm_w]

Did you have two channels enabled at the same time?

The sample rate of the analog channel is related to the current channel mode. The maximum real-time sample rate in the single-channel mode of the oscilloscope is 8 GSa/s. The maximum real-time sample rate in the half-channel mode is 4 GSa/s, and the maximum real-time sample rate in the all-channel mode is 2 GSa/s.

The current sample rate is displayed under CH SampleRate, and you can press More -> CH SampleRate to view it.

If you want to check the on screen display, you should be able to change the screen to "dot" mode and measure the time difference between the dots to give you a number. Oddly for me it was sometimes 10Gs/s so I'm not sure what was up with that..

If the screen is working but CSV is not, maybe its a bug.

[Mechatrommer]

even chinese got faked? how cheap is your MSO5000? anyone heard cloned Rigol?

[DaJMasta]

Check your acquisition settings, depending on the timebase and memory settings, a scope will often reduce the sample rate to improve update rate if left to its own settings.

Your scope seems to only have one ADC, as well, so if you have more than one channel enabled, your maximum sample rate will be lower.  The MSO5000 series can do 8GS/s on one channel, 4GS/s on two, and 2GS/s on all four, so if you have a second channel enabled, even if there's no signal connected, your maximum sample rate will be only 4GS/s.