Rigol's New DHO800 Oscilloscope unbox & teardown

[ebastler]

How did just swapping out the USB-C PSU mitigate the ripple/noise that was leaking into front end? I mean, my 804 came with the newer Liteon and I still see about the same noise pattern on the DC that was posted with the old PSU.

You measured some noise directly on the PSU's output voltage. The only measurements with the old PSU which I am aware of are showing noise patterns picked up by the scope, with nothing (or even a termination) connected to the inputs.

The fact that the patterns look qualitatively the same is not surprising, since both are noise patterns from switching power supplies. The fact that there was significant crosstalk into the scope front end with the old PSU, and no noticeable crosstalk with the new PSU, suggests that the noise from the new PSU is simply at a much lower level.

[AndyBig]

By the way, the screenshots above were taken while the oscilloscope was powered by a battery. This is noise generated by the oscilloscope itself, not by something external.

[ebastler]

By the way, the screenshots above were taken while the oscilloscope was powered by a battery. This is noise generated by the oscilloscope itself, not by something external.

Since you mentioned that the noise only occurs when you connect a probe, it must indeed come from an external source, right? If you clip a probe's ground lead to its tip, you make a nice little loop antenna which picks up signals from the environment.

If this noise bothers you, you can try switching all other nearby devices off. LED lights and switching power supplies are likely offenders. You can also try moving the probe end around and rotating it to see if things change. Or move the scope to another room (or a friend's place) to confirm whether the environment has an impact.

[AndyBig]

Since you mentioned that the noise only occurs when you connect a probe, it must indeed come from an external source, right? If you clip a probe's ground lead to its tip, you make a nice little loop antenna which picks up signals from the environment.

If this noise bothers you, you can try switching all other nearby devices off. LED lights and switching power supplies are likely offenders. You can also try moving the probe end around and rotating it to see if things change. Or move the scope to another room (or a friend's place) to confirm whether the environment has an impact.

This is the first thing I checked, because I understood that since these interferences are not there without the probe, it means they are induced by something external to the probe. These screenshots were taken when the oscilloscope was standing in another corner of the room, where there are no EMI sources within a radius of 5 meters. But the noise did not change or decrease at all. The amplitude of the noise increases significantly when I bring the tip of the probe with the loop of the ground wire closer to the oscilloscope, especially to the lower part.

[S2084]

I measured the noise of the "LITEON" power supply.  An external resistive load was connected and a voltage of 15 volts was triggered.  RIGOL itself was powered autonomously, from a power bank. Please note that this is the most extreme operating mode for this power supply, the oscilloscope will never consume that much... Typical power consumption is about 37 watts(15V 2.3A)

[Randy222]

I measured the noise of the "LITEON" power supply.  An external resistive load was connected and a voltage of 15 volts was triggered.  RIGOL itself was powered autonomously, from a power bank. Please note that this is the most extreme operating mode for this power supply, the oscilloscope will never consume that much... Typical power consumption is about 37 watts(15V 2.3A)

Can you zoom in on horizontal to the areas in this pic, set cursors to find frequencies of the ripples.
Do they show about 65kHz, 1.5MHz, and 33MHz ?

I do not recall seeing the noise after removing CH1 probe from the DC of PSU, so now I need to go check if such noise is still there just when connecting probe.

[Randy222]

Perhaps this ~280kHz "50% PWM" is emi coming from the LCD screen of the unit ! I not sure how the screen is actually painting the picture. It perhaps does look like the flat noise being offset on the screen, which then looks like PWM ?

I had probe set to AC 10x with the ground clip on ground lug at the 1kHz terminal.

Move probe closer to screen, amplitude (peak of "PWM") goes up, move away from screen and amplitude drops off fast.

I wonder how much noise these Rigol "packages" make?

But duly noted, I could not reproduce the noise I saw on the PSU DC when just having a floating probe attached. I was able to see something small at around 1.5MHz, but I might suspect that's just the noise from PSU coupling over to the floating probe ("antenna").

[S2084]

I can say that this power supply is not bad... but the noise from it is 200 millivolts from peak to peak, which is still a lot.  My power bank is half as noisy!  If anything, I use a Ugreen 145W power bank.  I don’t use this included power supply. All my sources with PD are much less noisy...

[Randy222]

Touchscreen EMI leakage? I wonder how much leaks into the probe wires?
Seems to be on-par with what I was seeing two posts back?

Edit - went sleuthing for that 1.5MHz I was seeing in PSU DC. Started up my SA4, found a -68dBm in a noise floor around -115dBm, turns out it's a local high-watt 1550 AM station. I also dug up some MuRata filter units I had from a project long ago, gonna try that on the PSU DC.

[S2084]

I made a short review of Android capabilities on Rigol
https://youtu.be/m4C0zKq4ay4

[beatman]

Crap capacitors on output of psu.I do a lot experiments just to see the behaviour with load on oscilloscope change the output capacitors from various cheap psus laptop adapters or phone chargers and solder same mf capacity panasonic fr series in most of cases the riple goes down from 20% to 70% tested on electronic load before and after.Sometimes make big difference  to change and the 400-450v cap on ac input with good quality but not always.Most important is the ESR of output caps.

[Randy222]

Nice video, note display here.

https://youtu.be/3OJnjXrAf5k?t=270

It's something that goes with "touchscreen" territory. Micsigs are similar out of the box but Micsig includes a matte screen protector with every 'scope. It really helps.

I'm waiting on a couple of screen protectors to try with my Rigol.

Glass or vinyl protector?

[AndyBig]

Glass or vinyl protector?

I pasted on a matte protective film for phones/tablets (hydrogel according to the seller). I got a lot of advantages: glare disappeared completely, fingers glide easier, no fingerprints remain. But it seemed to me that there is a minus - the small text is slightly blurred. But maybe it was just my imagination; I didn’t try to peel the film back and compare it carefully. So if the size of the film allows, then I would recommend first sticking a small piece on the part of the screen where there is small text (for example, on top, where the trigger parameters are displayed) and check whether the film will blur the text.
By the way, in the Android settings you can slightly increase the font size, then small inscriptions and numbers are better readable from a certain distance. But the markup is slightly slipping The screenshots show the standard text size and an enlarged one.

[S2084]

 \$\Omega\$I also applied a matte film, and yes, the text is a little blurry, but it doesn’t bother me at all since I used a custom and slightly larger font. The font was changed using this application
https://4pda.to/forum/index.php?showtopic=598323&view=findpost&p=33790100

[AndyBig]

\$\Omega\$I also applied a matte film, and yes, the text is a little blurry, but it doesn’t bother me at all since I used a custom and slightly larger font. The font was changed using this application
https://4pda.to/forum/index.php?showtopic=598323&view=findpost&p=33790100

Well, native fonts don’t really bother me, but thanks for the program, I’ll keep it in mind

[Randy222]

I will go with glass, just not 100% sure if glossy or matte.
https://www.amazon.com/dp/B0C6LJQJKX

[Fungus]

New trick:

When you have measurements on the side bar you can swipe them to the right to remove them.

[bulba99]

New firmware.

Code: [Select]

v00.01.02.00.02  2023/12/28

1. Self calibration optimization update
2. Solve the problem that window transparency cannot load the last value
3. Solve the problem that the LA function cannot display the label after setting it


v00.01.02.00.01  2023/12/5

1. Self calibration optimization update
2. Solve edge jitter below 31kHz

v00.01.02.00.00  2023/11/2

1. Self calibration optimization update
2. Solve the problem of UltraLab startup connection failure
3. Solve the problem of failure to save waveform in wfm format
4. Solve the problem of unresponsive touch on startup screen

https://download.rigol.com/cn/Firmware/Digital%20Oscilloscope/DHO800%26DHO900/DHO800_DHO900(Software)Updatev00.01.02.00.02.zip

[AndyBig]

New firmware.

Code: [Select]

v00.01.02.00.02  2023/12/28

1. Self calibration optimization update
2. Solve the problem that window transparency cannot load the last value
3. Solve the problem that the LA function cannot display the label after setting it


v00.01.02.00.01  2023/12/5

1. Self calibration optimization update
2. Solve edge jitter below 31kHz

v00.01.02.00.00  2023/11/2

1. Self calibration optimization update
2. Solve the problem of UltraLab startup connection failure
3. Solve the problem of failure to save waveform in wfm format
4. Solve the problem of unresponsive touch on startup screen

https://download.rigol.com/cn/Firmware/Digital%20Oscilloscope/DHO800%26DHO900/DHO800_DHO900(Software)Updatev00.01.02.00.02.zip

Something is wrong with self-calibration, they optimize it with every update...

[Fungus]

New firmware.
* Solve the problem that window transparency cannot load the last value
* Solve edge jitter below 31kHz

Some actual bug fixes!

I wonder if the window transparency fix also solves the other "didn't save state properly" bugs... like zoom setting.

Let's see...

[Fungus]

I wonder if the window transparency fix also solves the other "didn't save state properly" bugs... like zoom setting.

Let's see...

Nope. Window transparency is fixed but it still doesn't remember zoom setting.

[AndyBig]

Nope. Window transparency is fixed but it still doesn't remember zoom setting.

What zoom do you mean? When I turn it on, the scales of all channels are restored, and if the horizontal zoom was turned on, then it remains on after turning on the oscilloscope.

[Randy222]

Something is wrong with self-calibration, they optimize it with every update...

I was thinking the same thing.
Also, anything newer than 00.01.01.xx.xx is not available from the Rigol main sites? But available from a .cn download URL?
There's now three (3) newer FW's past 00.01.01.xx.xx

[AndyBig]

Also, anything newer than 00.01.01.xx.xx is not available from the Rigol main sites? But available from a .cn download URL?

Yes, this new firmware is available on the Chinese website. Both on the oscilloscope description page and in the support/download section.

There's now three (3) newer FW's past 00.01.01.xx.xx

Why not two? 00.01.02.00.00 and 00.01.02.00.02

[Randy222]

Also, anything newer than 00.01.01.xx.xx is not available from the Rigol main sites? But available from a .cn download URL?

Yes, this new firmware is available on the Chinese website. Both on the oscilloscope description page and in the support/download section.

There's now three (3) newer FW's past 00.01.01.xx.xx

Why not two? 00.01.02.00.00 and 00.01.02.00.02

I see three (3) versions of 00.01.02.00.xx FW's

Code: [Select]

[Model Supported] All the DHO800/900 series oscilloscopes
[Latest Revision Date] 2023/12/28

[Updated Contents]

v00.01.02.00.02  2023/12/28

1. Self calibration optimization update
2. Solve the problem that window transparency cannot load the last value
3. Solve the problem that the LA function cannot display the label after setting it


v00.01.02.00.01  2023/12/5

1. Self calibration optimization update
2. Solve edge jitter below 31kHz

v00.01.02.00.00  2023/11/2

1. Self calibration optimization update
2. Solve the problem of UltraLab startup connection failure
3. Solve the problem of failure to save waveform in wfm format
4. Solve the problem of unresponsive touch on startup screen

v00.01.01.00.02 2023/09/12

1. Self calibration optimization update
2. Update Help Documents

v00.01.01.00.01  2023/08/10

1. Remove all time-related displays on the instrument
2. To modify the vertical interface, click the wiring diagram to modify the AC coupling function
3. Modify the delayed scan Chinese display as Zoom
4. Modify the order of the menu in the upper right corner, put the measurement in the front and Default in the back
5. The probe ratio interface is removed, and the probe ratio option is added to the vertical first-level menu


v00.01.00.00.19  2023/07/24

1. The first version is released


-Released the production version.