New Rigol 16-bit function generators DG800/900 series

[Martian Tech]

Oscilloscope bandwidth is 100MHz

OK, that explains part of what you're seeing.  The bandwidth is the point at which the response drops to -3dB, so that is affecting your readings and giving more apparent falloff than is actually there.

[TK]

Hello everyone!
My DG811 version is 00.02.04.00.00, and I upgraded to 992 according to the method provided by Vtech.
But the output voltage is very different. What is the reason?

What is the bandwidth of your oscilloscope?

Oscilloscope bandwidth is 100MHz，DS1074Z ↑ DS1104Z

I tested on my setup (DG811 -> DG992), GW Instek GDS1054B scope (50MHz -> 100MHz) and I get 1.2Vpp with HighZ, direct BNC to BNC connection

[bd139]

Also ignoring the high Z input, if that scope input is 18pf at 100Mhz that’s a reactance of 88 ohms approx so you’ve got a voltage divider against the 50 ohms source there as well as the 3dB bandwidth fall off to contend with.

[jscm2000]

Please advise, after upgrading to 992, will the sampling rate be 250MSa/s? Is the waveform length 16Mpts?

[TurboTom]

Yes and yes...  Read here and the few following contributions. Btw, 250MSa/s it always was, on all instruments throughout the range. There's been some inconsistency regarding this issue in Rigol's documentation/advertising.

[Martian Tech]

A bit off the main topic of discussion, but just wondering if anyone else has tried operating one of these with an external timebase?  With mine, it runs OK for a while, then switches back to the internal timebase.  My source is a buffered OCXO, and the output voltage is within spec.  BUT I'm running 1.08 firmware - wondering if maybe upgrading to new firmware will fix it?

OK, I finally got around to acquiring a USB thumb drive that I could use to upgrade, so I can answer my own question.  Upgraded from 1.08 to 2.04 firmware, and the external reference works reliably now.

[bd139]

Is the DG811 hackable on all firmware revisions at the moment?

[TK]

Is the DG811 hackable on all firmware revisions at the moment?

you need to downgrade from 2.04

[bd139]

Thanks. That's good enough for me. 

[jscm2000]

Latest firmware, not tested

[PushUp]

You probably need a Chinese account - at least I could not login with my EU registration  to get the download file... I always get a sad smilie! 

...nearly at the end of this site...

https://www.rigol.com/supports/software-firmware-download_2.html

[bulba99]

I always get a sad smilie! 

Only a Chinese mobile number is accepted during registration.
An SMS with a verification code is sent to this number.
A colleague from China would have to help.

[Vtech]

I always get a sad smilie! 

Only a Chinese mobile number is accepted during registration.
An SMS with a verification code is sent to this number.
A colleague from China would have to help.

Here you go: https://rigol.com/Public/Uploads/uploadfile/files/ftp/EMD/DG/SOFTWARE/firmware/SardineII(ARM)Update_00.02.05.00.00.rar

No need to register - download link is present in javascript source code of the web page

EDIT: Release Notes: v00.02.05.00.00   2020-05-30
     - Solve the problem that the machine model changes to DG811 when upgrading to 00.02.04.00.00

I think there is no point of installing this.

[bulba99]

No need to register - download link is present in javascript source code of the web page

 

[tv84]

Release Notes: v00.02.05.00.00   2020-05-30
     - Solve the problem that the machine model changes to DG811 when upgrading to 00.02.04.00.00

 

[bulba99]

Release Notes: v00.02.05.00.00   2020-05-30
     - Solve the problem that the machine model changes to DG811 when upgrading to 00.02.04.00.00

 

This behavior probably applies to the DG2000 family and therefore there is only firmware 02.02 for this series on most websites.   

[TK]

Does anyone know the difference between DG992 and DG2102?  Can the DG811 be hacked to DG2102?

[tv84]

DG2000 has LAN interface built-in.

Nobody has tried it. Disregarding the LAN difference it could be possible or...  Nonetheless, don't see any value in that.

[jscm2000]

As far as I know, there are obvious individual differences in the DG800 series. Some 1Vpp can only reach 0.3 or 0.8. When you buy, it is best to filter if you have the conditions. I use a special method to make my DG811 reach the real DG992 standard. When 1Vpp, it shows 0.97Vpp. I will publish my test next time.

[jscm2000]

Using special methods and calibration, the output amplitude of DG811 in the high frequency range reaches the standard. DG811 truly becomes DG992!

[tv84]

Using special methods and calibration, the output amplitude of DG811 in the high frequency range reaches the standard. DG811 truly becomes DG992!

  Now, it would be cool if you share your calib method.

[Gandalf_Sr]

Using special methods and calibration, the output amplitude of DG811 in the high frequency range reaches the standard. DG811 truly becomes DG992!

  Now, it would be cool if you share your calib method.

What TV84 is asking is...

Please tell us how you did the calibration. What is your "special method"?

[mnementh]

Use a SDG6032X offscreen as "reference"...? 

mnem
 

[tv84]

DG800/900/2000 Performance Verification Guides.

[SMB784]

DG800/900/2000 Performance Verification Guides.

Is the performance verification guide for the various generators helpful in producing a correct calibration for a DG811 "upgraded" to a DG992?