Rigol's New Function Generator and DMM: DG800Pro / 900Pro / DM858

[csuhi17]

Naturally.
These three musketeers are just that kind.
I don't mind the 1-minute switch-on time, I let it warm up for a couple of 10 minutes. If I start doing something and use it several times, I don't turn it on and off...

This is also true for the DM858.
If I need to measure something quickly, my Owon HDS scope meter is there for that.
Or, according to my new habit, I use the Multimeter part of the Owon SPM, at my desk. 

I'm not going to throw away my Fy6800 either, it's more than adequate, if I need a more accurate and complex waveform, I'll turn on Rigol and while I wait, I'll occupy myself with something until then.

I can never understand why anyone would be bothered by the 1 minute power-on time with these devices. The minimum heating time is also written on more serious instruments.
Or does it have no practical use, and I just operated my devices unnecessarily?

[csuhi17]

I actually wonder what's below the metal shield. It seems small, Rigol doesn't do DMM chipsets so it will be someone else's chip there.

There you go.
At first I thought it was soldered on, but luckily it wasn't. 

[shapirus]

I wonder where the operating system is stored. What's under that secondary board that's installed in what looks similar to a laptop memory module slot?

[TurboTom]

Thanks for posting, now I'm seriously considering getting a DG821Pro instead of the SDG2042X (to be hacked into SDG2122X). But the boot time seems to be long enough to be annoying.

I'm pretty sure the user interface of the DG800/900 Pro is much more comfortable to use than the SDG2000X counterpart. The decent screen size with touch screen functionality ironed in right from the start is a big plus in contrary to the SDG2kX /6kX instruments that had their firmware origin in the SDG1k series w/o touch screen support...

But one thing that would really put me off getting Rigol's "Pro" series AWG is the use of a hybrid module as the channel output amps. They may be designed pretty well and beefy but there's always a hatch that "Murphy" slips through and the pamp may be damaged by mishaps... If the "standard" TI THS3091 / 3095 series current-feedback OPAMPs are used as drivers, there's at least a chance of a DIY hardware repair (calibation/adjustment to meet specs again may be a different story), but Rigol's output driver modules will probably be and stay pretty much unobtainium. It's even questionable if Rigol themselves will replace individual chips/hybrids instead of rather replacing the whole mainboard and swapping the SIMM style CPU module. If this would be substantially less expensive than the purchase of a new DG821Pro has yet to be found out.

One more thought on the DG800 -> DG900 series upgrade: With the "non-Pro-versions" the situation was pretty similar -- that is, the hardware is identical. Yet, we had to find out that the calibration isn't done to the full DG900 specs which results in an output level drop of ~2dB between 70 and 100MHz. Nevertheless, the liberated instrument is pretty well usable, but don't expect the situation to be much different with the "Pro" series. Rather keep your expectations low than getting disappointed afterwards...

Good luck! 

[zrq]

I would rather treat it as a consumer electronic product as it cost a fraction of an iPhone. If I blown up the front end by reverse power, then I buy a new one.
Also considering how fast the digital electronics are advancing today, hopefully by that time I can get one with even better specs. I was dreaming for but couldn't afford a second-hand Agilent 33250A when I was in high school, but today, meh...

Now the question is should I get a DG800Pro for hacking or a SDG2000X. I have the equipment to calibrate the frequency response if necessary. SDG2000X is a bit old now, I don't know if Siglent is going to release a newer model.

[thm_w]

I wonder where the operating system is stored. What's under that secondary board that's installed in what looks similar to a laptop memory module slot?

Everything is on that module, A40i-h SOM. RAM, CPU, flash. Similar to this sort of board: https://www.armdesigner.com/CM-A40i/
I don't know whats under though.

edit: DG821 pro is $333 - $40 coupon = $293 USD, https://www.aliexpress.com/item/1005006749594531.html
edit: It did show up via UPS.

[gbix]

i think DG800Pro as DG900Pro and calibrate it

[PELL]

Thanks @csuhi17 for teardown DM858

I am pretty sure the chip is HY3131 or HY3130, which is not good to see a handheld chip in a "Desktop Grade" product.

[PELL]

But one thing that would really put me off getting Rigol's "Pro" series AWG is the use of a hybrid module as the channel output amps. They may be designed pretty well and beefy but there's always a hatch that "Murphy" slips through and the pamp may be damaged by mishaps...

Yes, that is something definitely considerable when using it.

When you output at a very low amplitude, the wave comes directly from the DAC.

From what I can tell now, the "Custom ASIC" actually includes two dies, and you can see it in my teardown photo,  one is their own and the other one is some off-the-shell part.

[TurboTom]

The high-speed DACs used in these AWGs usually have differential current outputs, thus keeping voltage swing as small as possible. This signal is fed through the reconstruction filter and then to a trans-impedance amplifier to turn it into a single-ended voltage signal. This voltage signal is resistively added to an offset signal from an auxiliary DAC, amplified by a large output swing OPAMP. The individual resistors of this resistive adder are chosen to provide an impedance of 50 Ohms. As you mentioned, this signal is used directly or routed through a set of attenuators for low-level outputs. If a higher output level (or offset) is required, this whole signal is amplified typically by a THS3091 high-speed current feedback opamp. In most designs, there are three or four attenuator stages and the amplifier available to be routed via relays into the signal path.

Hence, a whole bunch of calibration constants, covering all amp/attenuator configuration combinations at several frequency points and offset conditions are required to fully tame such a complex contraption. Depending on the operational mode (i.e. amplitude or frequency sweeps, during which no attenuator switching is acceptable), even further calibraion points may be required. Fact is that on this forum, the calbration adjustment procedure for the legacy DG800/900 has not (yet) been figured out completely. Siglent's AWGs require some Python scripts to perform adjustments and I haven't seen any copies of those anywhere "in the wild". So a complete DIY adjustment looks pretty impossible, and I'ld assume it will be the same with the DG800/900 Pro AWGs.

It's well possible that, provided the right folks have a look into this problem, a solution can be found. But that will be a hell lot of work, and success cannot be taken for sure. Sorry for my doubtful attitude in this case, but as we've got a saying "A pessimist is an optimist with experience..." 

Cheers 

[gbix]

All DG800pro don't have calibration on high freq, but all DG900pro have full calibration
Commands for calibration I found and soon I documents it.
High freq table have 71 points to calibrate at double64 precision
Low freq is below 200khz and also have 78 points

[csuhi17]

I took out the DM858 card, you have to be careful, because there are small parts next to the catch plate, they are easy to break off.

[gbix]

I would rather treat it as a consumer electronic product as it cost a fraction of an iPhone. If I blown up the front end by reverse power, then I buy a new one.
Also considering how fast the digital electronics are advancing today, hopefully by that time I can get one with even better specs. I was dreaming for but couldn't afford a second-hand Agilent 33250A when I was in high school, but today, meh...

Now the question is should I get a DG800Pro for hacking or a SDG2000X. I have the equipment to calibrate the frequency response if necessary. SDG2000X is a bit old now, I don't know if Siglent is going to release a newer model.

What equipment do you have for calibration or what is enough to calibrate it?

[zrq]

I was thinking if what I need is amplitude calibration at higher frequencies, I have access to leveled spectrum analyzers and power meters.

[jackcheng]

last news for DG821pro
device can't produce frq above 200mhz ;(
but can do modulation (am and fm modulation) up to 200mhz

Hi qbix,

Would you willing to share how you do this? Or just some tips?

[gbix]

Would you willing to share how you do this? Or just some tips?

becouse activations not fully documented now/not tested, you can send me config files from /rigol/data folder to fix configuration

i soon will make new thread with info about activation and calibration dg800pro/900pro

[jackcheng]

Would you willing to share how you do this? Or just some tips?

becouse activations not fully documented now/not tested, you can send me config files from /rigol/data folder to fix configuration

i soon will make new thread with info about activation and calibration dg800pro/900pro

Can't wait for your instruction
By the way I found there is a `setup.stp` file under the /rigol/data/ folder. Is it the key file which need to modify for this magic?

[thm_w]

What is the SSH password? The usual root:Rigol001/Rigol201 etc doesn't work.

- The fan on this thing is horrific as mentioned, it starts off really slow for a few minutes (5V), then ramps way up (13V). 13V is even overdriving it as it is a 12V rated fan. Whoever designed that fan/heatsink should be slapped. Probably some intern. 70 or 80mm fan will have to go in.
- The font is not great, but nowhere near as bad as the DP900 font. Still regular font would be better, without the graininess.

edit: Code name is Dolphin Fish lol

                            Dolphinfish Business is Starting... \n",
         "/home/RIGOLTECH/sn03949/projects/dolphinfish_service/src/cpp/DolphinfishMain.cpp",

[shapirus]

- The fan on this thing is horrific as mentioned, it starts off really slow for a few minutes (5V), then ramps way up (13V). 13V is even overdriving it as it is a 12V rated fan. Whoever designed that fan/heatsink should be slapped. Probably some intern. 70 or 80mm fan will have to go in.

I thought it couldn't get worse that the DHO800/DHO900's fan. I was wrong, it can! It is already terrible at 8V, scary to imagine what it is like at 13V. And having variable speed on it doesn't make it any better.

I suggest checking the three DHO[8,9]00 threads (hacking, unboxing/teardown, and there was one more that I can't recall now): search by "fan" in them. There was a long discussion, and also a few solutions to the problem were described/demonstrated: from installing an external 120mm fan to lowering the speed of the stock fan to get an acceptable noise level while, as was claimed in that particular case, keeping the temperature at a reasonable level.

What is the power consumption level btw? I mean whole device, not just the fan -- I wonder if there's a real reason to run the fan at 13V. Does it draw more than the scope (35W IIRC)?

[csuhi17]

What is the power consumption level btw? I mean whole device, not just the fan -- I wonder if there's a real reason to run the fan at 13V. Does it draw more than the scope (35W IIRC)?

DG914ro
37W what i measured maximum.

When I switch between the counter and the second channel, the signal coming out of the first channel is interrupted during the switch.

[DaneLaw]

What is the SSH password? The usual root:Rigol001/Rigol201 etc doesn't work.

- The fan on this thing is horrific as mentioned, it starts off really slow for a few minutes (5V), then ramps way up (13V). 13V is even overdriving it as it is a 12V rated fan. Whoever designed that fan/heatsink should be slapped. Probably some intern. 70 or 80mm fan will have to go in.
- The font is not great, but nowhere near as bad as the DP900 font. Still regular font would be better, without the graininess.

edit: Code name is Dolphin Fish lol

                            Dolphinfish Business is Starting... \n",
         "/home/RIGOLTECH/sn03949/projects/dolphinfish_service/src/cpp/DolphinfishMain.cpp",

What model do you have?

[thm_w]

I thought it couldn't get worse that the DHO800/DHO900's fan. I was wrong, it can! It is already terrible at 8V, scary to imagine what it is like at 13V. And having variable speed on it doesn't make it any better.

Its worse with the variable speed if anything, startles you. Don't know if circuit is even working as intended, seems to hold the heatsink steady at ~38C.

I suggest checking the three DHO[8,9]00 threads (hacking, unboxing/teardown, and there was one more that I can't recall now): search by "fan" in them. There was a long discussion, and also a few solutions to the problem were described/demonstrated: from installing an external 120mm fan to lowering the speed of the stock fan to get an acceptable noise level while, as was claimed in that particular case, keeping the temperature at a reasonable level.

Thanks, I'll try a simple 80mm fan design to start off with. With a moderate 1.2W 80mm fan pointed toward the heatsink I get ~35C. I'll look around for a 24V 90mm fan and use that if I can.

What model do you have?

DG821 Pro from aliexpress link above.
- SN: DG8P255200045 (CAL says 2023-11-11 but software dates are 12-2023)
- Analog HW version 1
- Digital HW version 3

edit: added 80, 90, 92mm fan cover (see attached zip file)

[josfemova]

FYI, 800 Pro Series and 900 Pro series seem to have landed in tequipment.

https://www.tequipment.net/Rigol/DG821-Pro/Function-Generator/
https://www.tequipment.net/Rigol/DG902-Pro/Function-Generator/

[josfemova]

Now the question is should I get a DG800Pro for hacking or a SDG2000X. I have the equipment to calibrate the frequency response if necessary. SDG2000X is a bit old now, I don't know if Siglent is going to release a newer model.

I'm on the same boat but without calibration equipment. I would go for the Siglent one if it wasn't for the web control in the DG800/900 pro series which comes in handy for didactic purposes.

If recording the screen was not in consideration for me, I think I would be inclined to go with the Siglent

[tautech]

Now the question is should I get a DG800Pro for hacking or a SDG2000X. I have the equipment to calibrate the frequency response if necessary. SDG2000X is a bit old now, I don't know if Siglent is going to release a newer model.

I'm on the same boat but without calibration equipment. I would go for the Siglent one if it wasn't for the web control in the DG800/900 pro series which comes in handy for didactic purposes.

If recording the screen was not in consideration for me, I think I would be inclined to go with the Siglent

https://siglentna.com/operating-tip/sdg-remote-scpi-command-to-request-a-screen-image/