Siglent sds1104x-e memory depth

[frank2644]

Is there any disadvantage to setting the maximum memory depth to maximum for normal everyday use?

My SDS1104 shows a max mem depth of 14m while the default seems to be 140k. By setting the depth to max I don't want to affect other capabilities where memory is potentially needed, especially if the scope doesn't issue any timely warning messages. For example, no warning messages were apparent with the problem described below.

I was having a problem getting accurate frequency readings using the on screen measuring capability when measuring 250khz signals at a relatively slow, but required, sweep rate of 100ms. Setting the max mem depth to 14m seems to have cured the problem. The manual mentions this drawback as "Waveform Confusion" and is due to the number of sample points being to small to get an accurate waveform depiction. I guess that's a typical problem with digital scopes in general.

[Neutrion]

In theory it should mean no problems of using all the memory, but it can slow down the scope a bit.

[tautech]

Is there any disadvantage to setting the maximum memory depth to maximum for normal everyday use?

No, when is it is preferable to reduce the chance of aliasing.

My SDS1104 shows a max mem depth of 14m while the default seems to be 140k. By setting the depth to max I don't want to affect other capabilities where memory is potentially needed, especially if the scope doesn't issue any timely warning messages. For example, no warning messages were apparent with the problem described below.

I was having a problem getting accurate frequency readings using the on screen measuring capability when measuring 250khz signals at a relatively slow, but required, sweep rate of 100ms. Setting the max mem depth to 14m seems to have cured the problem. The manual mentions this drawback as "Waveform Confusion" and is due to the number of sample points being to small to get an accurate waveform depiction. I guess that's a typical problem with digital scopes in general.

Exactly, settings that will promote aliasing.
All your settings are in the tabs and with experience you can see how settings can influence results.
Using Dot mode occasionally helps understand why it's always preferable to have the maximum data points selected.

Actually I believe the default mem depth setting is 14M unless that been changed in recent firmware.....something I'll check and report back about when we predelivery check the next unit.

About the only thing I reduce is FFT points to speed FFT sweeps/writes when I need faster results however engaging Max Hold can be just as beneficial in FFT mode.

[bdunham7]

I was having a problem getting accurate frequency readings using the on screen measuring capability when measuring 250khz signals at a relatively slow, but required, sweep rate of 100ms. Setting the max mem depth to 14m seems to have cured the problem. The manual mentions this drawback as "Waveform Confusion" and is due to the number of sample points being to small to get an accurate waveform depiction. I guess that's a typical problem with digital scopes in general.

100ms/div means 1.4 seconds per screen.  At 250kHz, that is 350,000 cycles per screen.  Obviously 140,000 samples won't capture that very well, but 1.4M or 14M will.  This is a fundamental characteristic of a DSO, I'm not sure it should be called a 'problem'. 

[frank2644]

I recently updated to V6.1.37R8 (Release Date 12.10.21 ). There seems to be a later release, but it seems to be for the "operating system" vs. the other updates described as "firmware".

Here's the description: "SDS1xx4X-E Operating System -V2 (Only For 4-Channel models) (Release Date 01.11.22 )"

Does this apply to my scope?  When I display my system status I don't see any "operating system" nomenclature. I do see a parameter called "Uboot-OS Version 8.1". A quick search of my manual does not find a hit on "operating system".

Can anybody shed some light on this?
Thanks, Frank

[tautech]

I recently updated to V6.1.37R8 (Release Date 12.10.21 ). There seems to be a later release, but it seems to be for the "operating system" vs. the other updates described as "firmware".

Here's the description: "SDS1xx4X-E Operating System -V2 (Only For 4-Channel models) (Release Date 01.11.22 )"

Does this apply to my scope?  When I display my system status I don't see any "operating system" nomenclature. I do see a parameter called "Uboot-OS Version 8.1". A quick search of my manual does not find a hit on "operating system".

Can anybody shed some light on this?
Thanks, Frank

Yep, so to get all the features added in the last FW update, particularly the NTP clock feature that provides real  timestamps on saved files.
Easy to install as it runs at boot so the V2 update must be in the root of you USB stick for the scope to see it.
https://int.siglent.com/upload_file/zip/firmware/Oscilloscope/SDS1xx4X-E_OSV2_EN.zip

[frank2644]

100ms/div means 1.4 seconds per screen.  At 250kHz, that is 350,000 cycles per screen.  Obviously 140,000 samples won't capture that very well, but 1.4M or 14M will.  This is a fundamental characteristic of a DSO, I'm not sure it should be called a 'problem'.

 I troubleshot the wrong frequency, on and off, for two days before finally figuring it out. So indeed there is a "problem", but it's more likely me, not the scope.

Thanks,
Frank