DG4000 - a firmware investigation

[ted572]

DG4000 Calibration Restoration:

I just finished calibrating my DG4000 for Channel 1 and 2, and the frequency response is flat up to 200 MHz and well within better than +/- 0.8 dB.

So what is calibration? I have concluded that it is removing the un-calibration that you end up with after you install the firmware patch to extend the frequency!

So to calibrate (or rather restore the previous calibration of) your DG4000:  Press - Utility, Test/Cal, Secure Code, (put in PW) 2010, Enter, Secure OFF, (the result should be) Secure ON, Access gained.
Then for Cal. select HFLAT, Call Point (start at HFLAT 1-1), Measure Value, Input Value, press Save and wait for it to complete (about 3 seconds), select Cal Point for the next step.  Repeat for all 60 steps.  Then your done and you didn't have to connect anything up to your DG4000, except for AC power. Hi

Repeat for the remaining channel (only if you find it necessary, but I don't think that it will be).
 
   Cheers, Ted

[Rufus]

Then for Cal. select HFLAT, Call Point (start at HFLAT 1-1), Measure Value, Input Value, press Save and wait for it to complete (about 3 seconds), select Cal Point for the next step.  Repeat for all 60 steps.  Then your done and you didn't have to connect anything up to your DG4000, except for AC power. Hi

That isn't making any sense to me. What does "Measure Value, Input Value" mean?

If you can calibrate without connecting anything but mains why can't the thing self calibrate with one button?

[ted572]

Then for Cal. select HFLAT, Call Point (start at HFLAT 1-1), Measure Value, Input Value, press Save and wait for it to complete (about 3 seconds), select Cal Point for the next step.  Repeat for all 60 steps.  Then your done and you didn't have to connect anything up to your DG4000, except for AC power. Hi

That isn't making any sense to me. What does "Measure Value, Input Value" mean?

If you can calibrate without connecting anything but mains why can't the thing self calibrate with one button?

Measure Value :  Shows the current value (although apparently it may not be fully active) and outputs its frequency and level for you to measure.
Input Value:     :  Allows you can enter your new measurement value (from the Measure Value step above).

I don't how this fixes the issue with frequency response, just that it brings it all back to life, by Restoring the Original Calibration.  Running the Factory Restore by itself won't do it.   

Don't bother to measure or change anything.  Its not required or necessary.
Just follow the steps I provided to activate the current values that were somehow unactivated from the GEL patch.
If you have already changed some values, then I would exit and restore the Factory Defaults and then repeat the procedure I provided.  But, of course that's your option.
I'm of course starting to wonder if perhaps the same thing should possibly be done for AV, LFLAT, but certainly nothing else. Although I'm not going to go there at this time unless we spot a potential issue.

And by the way my frequency response up to 200 MHz looks to be +/- 0.5 dB or better so far.

Note:  Do the guys here with DG4000 FW 00.01.07.00.03 and the 'ppulse and npulse' issues have this patch installed, if so, could they be getting another artifact that could be related?  I don't know, but they may want to consider the possibility.

     Ted 

[Rufus]

I don't know why this fixes the issue with frequency response, just that it brings it all back to life. The Factory Restore by itself won't do it either.

Calling it calibration is what made it confusing since you are not calibrating, just going through some motions which appears to re-instate an existing calibration.

[ted572]

I don't know why this fixes the issue with frequency response, just that it brings it all back to life. The Factory Restore by itself won't do it either.

Calling it calibration is what made it confusing since you are not calibrating, just going through some motions which appears to re-instate an existing calibration.

Yes,  we are Restoring the Original Calibration.  And you are correct, the description was incorrect, but then this is a new revelation of what is going on in the DG4000.

[KedasProbe]

Interesting, you have a DG4062 but the stored call settings (but not 'activated') gives you a flat responds even higher than 160MHz.

So it looks like reducing the unit to 60MHz is done after the full factory calibration of the PCB
or there is some nice self calibration feature build in that is used during this procedure.

[Teneyes]

DG4000 Calibration Restoration:
   So to calibrate (or rather restore the previous calibration of) your DG4000:

Press - Utility, Test/Cal, Secure Code, (put in PW) 2010, Enter, Secure OFF, (the result should be) Secure ON, Access gained.
Then for Cal. select HFLAT, Call Point (start at HFLAT 1-1), Measure Value, Input Value, press Save and wait for it to complete (about 3 seconds), select Cal Point for the next step.  Repeat for all 60 steps.  Then your done and you didn't have to make measurements or level changes.  You didn't even have to hook anything up to your DG4000 except for AC power. Hi

DG4000 Calibration Restoration:
I think the  steps:
   "Measure Value",
   "Input Value",
   "Rotate select next cal Point"
 can be stepped thru the 62 points and then save only once to save time.

[ted572]

Interesting, you have a DG4062 but the stored call settings (but not 'activated') gives you a flat responds even higher than 160MHz.

So it looks like reducing the unit to 60MHz is done after the full factory calibration of the PCB
or there is some nice self calibration feature build in that is used during this procedure.

No, I do Not think this is the case.

[ted572]

DG4000 Calibration Restoration:
Re. Sniffing the Rigol's internal I2C bus, Reply #1771

I now believe that the Restoration of the DG4000 calibration should be done for AC, LFLAT, and HFLAT to correct some other potential glitches.  Nothing is being changed, or has to be connected to the DG4000, so the process goes fast.  Just bring up and save all the default values for each step, starting with 1, or 1-1 (A/R).
You can also do this for 'Inner Imped' and 'Offset', although I haven't seen a case or benefit for it yet.

I just wouldn't do this for Freq Accuracy, or Counter, unless you see a need for it, and then you should complete this cal. process as prompted.

The calibration restoration is effective for both channels, it isn't necessary to repeat each cal. routine for the other channel.

[cybernet]

if somebody wants to fiddle with it - DG4000 supports 2 file types.

.CDF  - "RIGOL:DG4:CALIBRATION DATA FLASH FILE"
.CDV - "RIGOL:DG4:CALIBRATION DATA VOLATILE FILE"

my, guess its that what they use at the factory. i dont see any flash routines called for the CDV files (the parser is the same)
here is what i know:

file content:

RIGOL:DG4:CALIBRATION DATA VOLATILE FILE<X*0xb14><X*0x654><0x4230>[ <X*0xb14><X*0x654> ]
if X = 1 then the bytes in [ ] are expected too.

cant see where X is coming from atm - but maybe somebody figures out a relation of the sizes to the cal items. i wasnt successfull in that.

[Rigol-Friend]

Hello to all,

I got arround the same plot on DSA815 like PeDre (before calibrating) as I sweeped up to 200 Mhz.

Sorry, but I don't understand the calibration procedure. I'm not an expert    and my english is poor also.

For example: I find ID1  HFLAT-1-1 (Meas Val) 11.8650 dBm. Ok, I can enter a new value now, but which value?
And what meens HFLAT-x-x ? Is it corresponding with a frequency or frequency-range?

Thank you for help
Rigol-Friend

[Rigol-Friend]

@Pedre

Thank you for your fast answer, I will try it after dinner.   

[Rigol-Friend]

Very good, PeDre, it works fine, thank you.

I have an output difference between 10 Khz and 200 Mhz of maximum arround 0.5dB. I measured this with DSA815 and Rohde&Schwarz URV35 with URY Z2 Detector. I adjusted the frequencies by hand.

But not so in sweep-function. Adjusted 0dBm of DG4202 produces arround 5dBm until 100Mhz and higher the output falls down till 0dBm at 200Mhz.

Rigol-Friend

[ted572]

DG4062 to DG4202 Internal Calibration Info provided at the following:
Sniffing the Rigol's internal I2C bus,  Post #1785,  https://www.eevblog.com/forum/testgear/sniffing-the-rigol%27s-internal-i2c-bus/msg344008/#msg344008

[ted572]

Does anyone else observe this? (FW=1.04)
When doing a sweep (6 sec ) from 100 ->160 MHz that the output is mostly Flat
about 1 Vpp  , see Pix 1

But when the sweep is set to  100 ->161 MHz
the out jumps to 1.42 Vpp (@100MHz) and the sweep looks like Pix 2

Note At the end of the sweep the output is at 1 Vpp (60sec end Hold)
        see Pix 3

Is this a FW issue, a limit, a bug, or a Calibration error  ?

Can you try to do the Calibration Restoration for everything else except for 'Freq. Accuracy' and 'Counter'  to see if that fixes the Sweep Freq Response?

It would also be nice to know what this looks like on an original (as received) DS4162.  Maybe someone can comment that has one of them.

Thanks, Ted

[ted572]

DG4000 Calibration Restoration:
The calibration restoration is effective for both channels, it isn't necessary to repeat each cal. routine for the other channel.

I am not sure of "effective for both channels" is true ??
In pics I show a glitch on chan 2 out (6sec sweep 1->160MHz) at about 24 MHz
there was no clitch on Chan 1
I restored ALL of Chan 2 HFLAT and the glitch was corrected

I have had others tell me that sometimes they have a glitch, fault, or otherwise strange behavior with the DG4000,  and they reset or Power OFF/ON and the issue goes away.  Have you observed anything like this?  Anyway what you reported above could possibly this kind of thing. No one else has said anything about having do do a Cal. for both channels. Although of course it is possible, I think somewhat unlikely.

[Teneyes]

Here are 2 Animated displays  of an auto freq. sweep of a sine wave on DG4000
  1) from 10-160MHz
  2) from 10-161MHz

DSO recording was used to capture 160 frames at 75msec during the sweep
every 10th frame is shown:
       on 1) very little variation of Vp-p
       on 2) Vp-p  starts high and ends at correct value

Again does anyone see this variation on their Rigol  DG4000??
Cannot say this is a Bug

[KedasProbe]

Is 10-159MHz also OK?
(in theory you can't enter >160Mhz so...)

[Rigol-Friend]

Yes this "bug" is known. See https://www.eevblog.com/forum/testgear/dg4000-a-firmware-investigation/msg343895/#msg343895

I think, it's maybe a problem with the hardware. Rigol offers the "right" 4162 with maximum frequency limited of 160 Mhz.
I think that has a reason.

[whotopia]

Hi all,

Silly question, but could someone please post instructions on how to upgrade firmware on DG4000?  I got a DG4062 for Xmas, ran the cengen output and would now like to upgrade to latest firmware. Unfortunately the Rigol site's beyondmeasure.rigoltech site seem to not be working for the past few days, and thus I can'd download http://beyondmeasure.rigoltech.com/acton/attachment/1579/f-0115/0/-/-/-/-/file.pdf  (the upgrade instructions).  (yes I've search around this forum and others)   

Thanks!
Steven

[Rigol-Friend]

Hi whotopia,

I tried it some minutes ago and got this PDF without any problem. For you I attached here.

[AndersAnd]

Hi whotopia,

I tried it some minutes ago and got this PDF without any problem. For you I attached here.

The website seems to b up an running again. I tried without luck to download it after whotopia's post.
But now I have just tried again and now it works.

[whotopia]

Thanks everyone for the instructions and help.  Upgrade worked fine, but I did need to go through 4-5 memory sticks before I found one that the Rigol would accept.  Seem like I'm not the 1st person with that problem.

[snipor]

@Rigol-Friend
Would it be possible that you take a quick look in your Message Box?
Thanks

[roket]

hi, everybody! there is at somebody file CyberNet  http://pastebin.com/ipkJCxPM   ?