Hacking the Rigol DHO800/900 Scope

[Randy222]

That was my first try at File.io, let me try dropbox...
https://www.dropbox.com/scl/fi/qdo6kfje8coxgxbgp9012/DHO800_DHO900-Software-Updatev00.01.02.00.00.zip?rlkey=35rzumxdyw7g6qfsv8j9flztr&dl=0

I went for the 914 to gain the CAN decoders since I frequently work with CAN bus stuff. Otherwise the BW upgrade would have been fine. I'm hesitant to buy a probe and cut a hole in my case since my cutting skills aren't pretty and I have a Saelea pro 16 on hand.

Just some observations.
All of the 01.01 downloads use a CAP V in their name (UpdateV), the 01.02 zip used a lower case v.
Also, the 800 series is missing digi header, so not only would you need to cut a hole in case, would also need to solder header to board, and there was chatter about some mem chips missing in 800's.

[Randy222]

Where I can download DHO914 vendor.bin? Can't find in this topic (

I found this tool https://github.com/zelea2/rigol_vendor_bin and successfully changed model to DHO914 in my own vendor.bin

Do you still have your original vendor.bin file?
If so, can you get a diff?
eg;
name each with "oem" and "edit"

vendor.oem.bin and vendor.edit.bin
xxd vendor.oem.bin vendor.oem.hex
xxd vendor.edit.bin vendor.edit.hex

then diff them
vimdiff vendor.oem.hex vendor.edit.hex

post pic of the diff

[t_i_t_o]

I can confirm - 1.02 along with 924 vendor.bin does not show the offset issue.

[Randy222]

I can confirm - 1.02 along with 924 vendor.bin does not show the offset issue.

Please add clarity.
You used the bin tool to mod model number in your 800 vendor.bin file. You did not adb push (copy in) a vendor.bin from a 900, correct?

[t_i_t_o]

Yes, I simply modded my 804 vendor.bin to a 924 one and pushed it to the scope.

[Randy222]

Yes, I simply modded my 804 vendor.bin to a 924 one and pushed it to the scope.

See my reply #682, can you do that for the forum folks?

[Demon Xanth]

I can also confirm that my "Baseus Power Bank, 65W 20000mAh". will power the scope just fine. Though plugging it into my Pine power 120W desktop PSU killed the 10 pin power delivery controller IC. I have yet to identify it and there are no markings.

[4agr]

I have 1.02, just adb push 924 vendor.bin downloaded from here, no offset after selfcal.
but I found WIN+N to andorid, it warns SDcard broken. The scope works well now.

[enson72]

It has been determined for a long time. The noise is caused by the design of the execution. Air raid sirens are designed according to this principle.

Some fans whine at certain pwm frequencies.  Are you saying that you know for a fact that this is not a contributing factor in DHO800 oscilloscopes?

This is a well known problem in the diy 3d printer community.  A quick search shows this has been discussed here too.  At least one thread here has a better test suggestion.  Instead of using pwm, use a variable power supply to see if it reduces the fan noise.
Eg. https://www.eevblog.com/forum/beginners/filtering-pwm-to-smooth-dc/

Why complicate it? It's much simpler. You take the fan out of its socket and realize that it is not making noise)) You can easily find information on how an air alert is set up on Google. I screwed an external cooler to Rigol, and no PWM prevents it from working quietly. Take a look and everything will become clear. In the photo there is an air raid siren

I never suggested removing the fan, just connecting it to a different power source.  Taking the fan out of the case may change how it resonates. 

Anyhow as the sound doesn't bother me at all, I won't be opening mine.  I was trying to offer something to try which may offer a less physical hacking way to reduce the sound for those who it does annoy.  For all I know the fan runs on DC rather than PWM.

On the second day after the purchase, I was looking for an interference in the amplifier. The growl of the DHO cooler drowned out the sound of the speaker for me. And it was very annoying. Without hesitation, he opened, removed this ratchet and put on an external cooler. And if you listen to this nightmare all day, your head will be square by evening. 7 coolers in my computer are almost inaudible, and one DHO roars like a bike. ))

[Randy222]

On the second day after the purchase, I was looking for an interference in the amplifier. The growl of the DHO cooler drowned out the sound of the speaker for me. And it was very annoying. Without hesitation, he opened, removed this ratchet and put on an external cooler. And if you listen to this nightmare all day, your head will be square by evening. 7 coolers in my computer are almost inaudible, and one DHO roars like a bike. ))

"coolers"? Is each "cooler" a fan? If you can't hear 7 fans running then I suspect they are all running at like 200rpm.

Noise comes from mostly airflow. To get some flow from a tiny fan it needs to run fast rpm's. More flow + smaller fan, is a catch-22 design in terms of noise. Bigger fan blades can 1) run slower, and 2) have better designed blades to help mitigate wind noise. But sometimes physical size and costs become more of a factor when the noise is still in that "acceptable" range.

Pop open case, inline a resistor with the tiny fan, install a 90x15mm on ext side. That's what I will do, but I have more to do along the way, gonna be testing the noise on the provided usb-c psu, then I will add some filtering. I will skip doing any PWM control on the ext fan side to avoid any harmonics stuff since I will split the usb-c to power both DHO and ext fan, so just gonna use a generic pot to slow the ext fan into the right flow.

[Demon Xanth]

It might just be the amount of other fans that are running in our shop, but I can hear my fan and don't find it annoying at all. I have to actively listen for it to notice it. Other power supplies and test fixtures easily drown it out.

[enson72]

On the second day after the purchase, I was looking for an interference in the amplifier. The growl of the DHO cooler drowned out the sound of the speaker for me. And it was very annoying. Without hesitation, he opened, removed this ratchet and put on an external cooler. And if you listen to this nightmare all day, your head will be square by evening. 7 coolers in my computer are almost inaudible, and one DHO roars like a bike. ))

"coolers"? Is each "cooler" a fan? If you can't hear 7 fans running then I suspect they are all running at like 200rpm.

Noise comes from mostly airflow. To get some flow from a tiny fan it needs to run fast rpm's. More flow + smaller fan, is a catch-22 design in terms of noise. Bigger fan blades can 1) run slower, and 2) have better designed blades to help mitigate wind noise. But sometimes physical size and costs become more of a factor when the noise is still in that "acceptable" range.

Pop open case, inline a resistor with the tiny fan, install a 90x15mm on ext side. That's what I will do, but I have more to do along the way, gonna be testing the noise on the provided usb-c psu, then I will add some filtering. I will skip doing any PWM control on the ext fan side to avoid any harmonics stuff since I will split the usb-c to power both DHO and ext fan, so just gonna use a generic pot to slow the ext fan into the right flow.

No, they work at a normal speed. Usually about 60%. When rendering, the coolers are at 100%. The loudest ones are on the video card. And it's quieter than DHO. It's just that when the cooler started making sounds on the Zalman power supply after a year of operation, I replaced it with Be Quiet. Noctua was installed on the processor after a year of operation. The cabinet ones also Be Quiet. It's just about the quality of the coolers. Only the air flow is audible. In DHO, with this design, the quality of the cooler does not matter. Do you want to slow it down? There is already 8V, usually the coolers start rotating starting from 5V. In addition, even at 8V in the DHO settings, you can see a temperature of about 60C. It's not critical, but it's not 40 anymore. Now I have a maximum temperature with an external cooler that I have seen- 55C. And silence. I bought DHO for comfortable work, and if the warranty prevents it, then I don't need it.

[Houseman]

I'm not sure what went wrong with my previous upgrade attempts, because I sent the identical string, but I tried it again after power cycling the DHO914S and it worked!

Unlike the other Rigol scopes I have, the BW upgrade doesn't show up as an option in the options list, but does show "Max BW:250M" in the "About" section.

Thanks to all who had the patience to help me with this!

Hi, I order a 914s from China and it is on the way. Can you post steps to upgrade to 924s in detail?

Hi. Any news regarding upgrade from 914S to 924S with vendor.bin file?
I was also interested into that topic.
Best regards

[Randy222]

On the second day after the purchase, I was looking for an interference in the amplifier. The growl of the DHO cooler drowned out the sound of the speaker for me. And it was very annoying. Without hesitation, he opened, removed this ratchet and put on an external cooler. And if you listen to this nightmare all day, your head will be square by evening. 7 coolers in my computer are almost inaudible, and one DHO roars like a bike. ))

"coolers"? Is each "cooler" a fan? If you can't hear 7 fans running then I suspect they are all running at like 200rpm.

Noise comes from mostly airflow. To get some flow from a tiny fan it needs to run fast rpm's. More flow + smaller fan, is a catch-22 design in terms of noise. Bigger fan blades can 1) run slower, and 2) have better designed blades to help mitigate wind noise. But sometimes physical size and costs become more of a factor when the noise is still in that "acceptable" range.

Pop open case, inline a resistor with the tiny fan, install a 90x15mm on ext side. That's what I will do, but I have more to do along the way, gonna be testing the noise on the provided usb-c psu, then I will add some filtering. I will skip doing any PWM control on the ext fan side to avoid any harmonics stuff since I will split the usb-c to power both DHO and ext fan, so just gonna use a generic pot to slow the ext fan into the right flow.

No, they work at a normal speed. Usually about 60%. When rendering, the coolers are at 100%. The loudest ones are on the video card. And it's quieter than DHO. It's just that when the cooler started making sounds on the Zalman power supply after a year of operation, I replaced it with Be Quiet. Noctua was installed on the processor after a year of operation. The cabinet ones also Be Quiet. It's just about the quality of the coolers. Only the air flow is audible. In DHO, with this design, the quality of the cooler does not matter. Do you want to slow it down? There is already 8V, usually the coolers start rotating starting from 5V. In addition, even at 8V in the DHO settings, you can see a temperature of about 60C. It's not critical, but it's not 40 anymore. Now I have a maximum temperature with an external cooler that I have seen- 55C. And silence. I bought DHO for comfortable work, and if the warranty prevents it, then I don't need it.

Fan blade speed will be proportional to flow rate for any given fan. Fan blade speed must increase as fan gets smaller for any constant flow rate. Little fans make more noise.
Swap out your fans for little ones, adjust to get require flow, noise will go way up.
The DHO800/900 is a tiny box, so not easy to put a large low rpm fan inside. And perhaps the tiny fan is just a low quality sleeve bearing item?

But duly noted, that warranty foil sticker, you can buy them from many china sources. 

However, I do believe there is a way to control that tiny fan speed from within a file somewhere.

[enson72]

You can adjust the speed, make it smaller. And get 75C at 24C in the room and more than 80C in the summer. I don't like this idea. Rigol has done everything to reduce the body. But let me have it a little more, but without noise. There are experiments in this video. But I advise you to look at the temperature not only on the radiator surface, but also in the Rigol menu. In any case, he did not achieve a quiet job.

[Randy222]

Yes, I simply modded my 804 vendor.bin to a 924 one and pushed it to the scope.

I was playing around with that rigol_vendor.bin tool. It does not modify any bin file, it just creates them. If you supply
So when you say "modded", was that a manual hex edit, or you just created new bin and pushed that in?

If you pass in only a filename "rigol_vendor_bin myBinFile.bin", it decodes the file.

For readers, if you do a manual set of serial using the tool, only the last 7 digits in your UTIL ABOUT serial is the serial number.
The 1st six chars are series chars, eg 800 series will all be "DHO8A25", 900 "DHO9A25", etc.

[Randy222]

Here are few other things that might be of use:
1) Setting HDMI resolution - on DHO800 line there is no direct menu item to set the resolution - for some reason my monitor got 1920x1200 and the output did not look right - here is a quick fix: 

Much easier: Tap the "about" button three times and you get settings for the HDMI resolution.

I have the 01.02 firmware, when I tap "about" in UTILITY --> ABOUT 3x it toggles a "TestModel" option ON or OFF.
What is "TestModel" ?

When set to TestModel:ON I can then click OTHER to get to HDMI settings, which also contains the open source acknowledgement option to read it.
When set to TestModel:OFF the OTHER menu item only shows the open source agreement item, but if I tap OTHER it flashes the HDMI settings page for a 1/4sec and returns back to the open source display.

[t_i_t_o]

rigol_vendor_bin shows info about the provided vendor bin, if no other arguments are provided. If you provide -m and a model name, it will create new vendor.enc file with new model based on the provided vendor.bin. Now you need to rename vendor.enc to vendor.bin and push to your scope. Have you RTFM? That is how I modded my vendor file.

[Randy222]

rigol_vendor_bin shows info about the provided vendor bin, if no other arguments are provided. If you provide -m and a model name, it will create new vendor.enc file with new model based on the provided vendor.bin. Now you need to rename vendor.enc to vendor.bin and push to your scope. Have you RTFM? That is how I modded my vendor file.

-M

not -m

 

[Silver_Is_Money]

Do the same hacks as for the DHO804 also work for the 2 channel DH802 version?

[t_i_t_o]

Try them and let us know : )

[Randy222]

Question about that rigol bin tool.

When using the -o option to gen all the scpi options, is it specific to hardware version (dho800 vs dho900), or specific to the vendor.bin version?

Eample, my 804 is now a 914 via just the vendor bin mod using the tool. But do I gen options for DHO800 or DHO900 ? The hardware is still "12" for DH800, not an "8" for DHO900, as seen in UTIL --> ABOUT.

The tool generated a ton of scpi option strings, but obviously not all of them will apply to the 800 hardware, so which ones are the useful ones?

[vanyas]

Question about that rigol bin tool.

When using the -o option to gen all the scpi options, is it specific to hardware version (dho800 vs dho900), or specific to the vendor.bin version?

Eample, my 804 is now a 914 via just the vendor bin mod using the tool. But do I gen options for DHO800 or DHO900 ? The hardware is still "12" for DH800, not an "8" for DHO900, as seen in UTIL --> ABOUT.

The tool generated a ton of scpi option strings, but obviously not all of them will apply to the 800 hardware, so which ones are the useful ones?

You have to gen options for dho900 by specifying modified vendor.bin

[JDW]

Unlike most people, I found no offensive odor at all when powering on my DHO804. 

And unlike most people, I've not found the fan offensive.  Would love it silent (no fan) but it's not as bad as I thought based on what other people said.

I also completed the hack, largely using this video...



But I did it using an Apple Silicon M1 MacBook Pro.

Sadly, batch files don't work on the vastly superior computing platform we know as the Mac.  You therefore must install Parallels Desktop Trial (Windows on Arm), but there are yet more hoops to jump through. 

You can't download the Hack ZIP archive and leave it in the normal location or Windows (in Parallels) will complain that UNC paths are not supported.  Blasted all!  The workaround is to move the decompressed ZIP folder into your /Program Files (within Parallels Desktop).  But then it still won't work because you must edit Properties and change permissions so contents of that folder can be edited/added!!  Then you need to run the *.bat file as Administrator via right-click on the *.bat. 

Of course, your scope must be connected to your local network (I used an Ethernet cable), and you need to edit the *.bat file as explained in the video, which I did, of course, prior to what I just told you.  In the end it worked, but there needs to be a Mac version that is not a *.bat file but rather an *.sh file which will run in the MacOS Terminal.  That would eliminate the use of Parallels Desktop entirely, which is a huge headache.

Anyway, my DHO804 is not 100MHz with 50M memory, and no silly DHO900-series non-functional menus to mess with my mind.  It's the ideal setup.

[Proxy64]

In this youtube video, it use a shargeek stormpower bank, on this display we can see the DHO use 15V between 2.150 - 2.650 A, I think it is an interesting information for those who want to power the fan through the usb+c (there is not so much power available and it’s not 12V!).


https://youtu.be/TXL916et9_Y?si=ufldtgFa_a2auhS4