Author Topic: Hantek 6022BE 20MHz USB DSO  (Read 636973 times)

0 Members and 5 Guests are viewing this topic.

Offline PedroDaGr8

  • Super Contributor
  • ***
  • Posts: 1283
  • Country: us
  • A sociable geek chemist
Re: Hantek 6022BE 20MHz USB DSO
« Reply #525 on: March 30, 2014, 03:18:59 am »
This is what I was saying earlier. Speakers are inherently non-linear devices. A speaker rated at 2ohms can go as high as 20 ohms depending on the frequency. Plus stability at one frequency does not inherently guarantee stability at all. To ensure that you need to do a sweep and look for clipping at all relevant frequencies.
The very existence of flamethrowers proves that some time, somewhere, someone said to themselves, "You know, I want to set those people over there on fire, but I'm just not close enough to get the job done." -George Carlin
 

Offline Mark_O

  • Frequent Contributor
  • **
  • Posts: 937
  • Country: us
Re: Hantek 6022BE 20MHz USB DSO
« Reply #526 on: March 30, 2014, 04:11:27 am »
This is what I was saying earlier. Speakers are inherently non-linear devices. A speaker rated at 2ohms can go as high as 20 ohms depending on the frequency. Plus stability at one frequency does not inherently guarantee stability at all. To ensure that you need to do a sweep and look for clipping at all relevant frequencies.

Completely correct!  However, if the OP (and those in the videos linked to) cared about when clipping really started, they would be looking for distortion products (spurious harmonic components) in the frequency domain, and not for visible deformation of the sinusoidal waveshape. 

At one point in the Velleman video, the author said something like, "There, that looks clean... so XX watts".  When in fact, there must have been at least 5% distortion in the waveshape at that point.  And in the first video, the demonstrator cranked the amplitude up so it was clipping so hard it looked like a square wave (at 400W!).  I was cringing, thinking how if an actual speaker had been hooked up, he would have blown the cone right off it.   :scared:

This is just a rough metric, but it apparently has some value in certain contexts, since the claimed ratings are apparently bogus in many situations.  I.e., advertising hyperbole.
 

Offline pickle9000

  • Super Contributor
  • ***
  • Posts: 2152
  • Country: ca
Re: Hantek 6022BE 20MHz USB DSO
« Reply #527 on: March 30, 2014, 05:08:41 am »
To be honest I was only interested in the math being performed in the scope.

As for audio related discussions online... no comment.
 

Offline marpolsdofer

  • Contributor
  • Posts: 7
Re: Hantek 6022BE 20MHz USB DSO
« Reply #528 on: March 30, 2014, 08:19:31 am »
I do have a CD to preform all needed frequency and test them each, at least what everyone seems to use.

As for distortion detectors like the SMD DD-1 I did not discover it until the day I got the scope.

I don't plan on being at more then half level much if at all so I think this will do, besides it does have other uses. I could have used this a few other times.

Thanks for you help guys.

I don't run across many people talking bout dummy load when seating up the amp. This video as hiding on youtube but this actually stuff better then most people. 
« Last Edit: March 30, 2014, 08:33:01 am by marpolsdofer »
 

Offline Matchless

  • Regular Contributor
  • *
  • Posts: 119
  • Country: za
Re: Hantek 6022BE 20MHz USB DSO
« Reply #529 on: March 30, 2014, 09:05:20 am »
 Eric,
       I have redrawn your schematic to make it easier to fit a page in the manual. I also made some small changes. Would you be so kind as to check it over. I usually make mistakes!
Thanks.

Here it is: http://jmp.sh/bEsySoI

Thanks

Edit updated picture
« Last Edit: March 30, 2014, 11:02:50 am by Matchless »
Regards
Matchless
 

Offline Fraser

  • Super Contributor
  • ***
  • Posts: 9441
  • Country: gb
Re: Hantek 6022BE 20MHz USB DSO
« Reply #530 on: March 30, 2014, 03:57:58 pm »
Your probe schematic looks a bit odd with X1/X10 and X100 next to it. I only see a X1/X10 probe.
 

Offline Matchless

  • Regular Contributor
  • *
  • Posts: 119
  • Country: za
Re: Hantek 6022BE 20MHz USB DSO
« Reply #531 on: March 30, 2014, 04:21:12 pm »
You are right, I meant to add x100 as well, changed my mind and did not remove that.
Regards
Matchless
 

Offline lapeyroua

  • Contributor
  • Posts: 8
Re: Hantek 6022BE 20MHz USB DSO
« Reply #532 on: March 30, 2014, 06:00:46 pm »
Matchless :
at Mux output, R5 is 1k Ohm (R5, R6 R7 refer to R18 R19 R22 on the PCB)
Please suppress the diodes reference (2N000) in the AD9288, it's a dummy reference inserted by my software.

About 6022's design
The diagram is not complete. The ADC measures the signal between pin 2 and pin 3 (respectively 11 and 10 for channel B)
I don't see where pin 10 or 3 are connected on the PCB. What sounds strange for me is that there is no offset at ADC input.

So I suppose the complementary input to be grounded

AD9288 data sheet : The nominal input range is 1.024 V p-p centered at VD × 0.3
Hantek's design seems to be centered at 0V

applying -5V referred to ground  at the box input (Vin) roughly means -0,5V at ADC input. The ADC data sheet lists -0,5V as max rating for the Analog inputs.
Big stress if you exceed the -5V..
I hope something is wrong in the diagram. The only ADC protection are the diodes shown in the Equivalent Analog Circuit of AD9288.
The A7 diodes protect the input of HRA but with this protection, -5V could be applied to the AD9288 input (100mA in the diode, reduced to 90 thanks to the HRA short-circuit output limitation).

The answer may be in the AD9288 data sheet : Special care was taken in the design of the analog input stage of the AD9288 to prevent damage and corruption of data when the input is overdriven.

 

Offline lapeyroua

  • Contributor
  • Posts: 8
Re: Hantek 6022BE 20MHz USB DSO
« Reply #533 on: March 30, 2014, 06:17:24 pm »
If the members agree with the fact that the complementary input is grounded, the diagram would be modified as attached
http://jmp.sh/PSIBOEv
 

Offline Matchless

  • Regular Contributor
  • *
  • Posts: 119
  • Country: za
Re: Hantek 6022BE 20MHz USB DSO
« Reply #534 on: March 30, 2014, 06:38:12 pm »
Eric, thanks I have updated the schematic.
I will add the ADC change also after hearing what the others have to say about it.
Did you see the 6022be manual states that the input protection is 35V p-p?
Regards
Matchless
 

Offline lapeyroua

  • Contributor
  • Posts: 8
Re: Hantek 6022BE 20MHz USB DSO
« Reply #535 on: March 30, 2014, 08:19:37 pm »
OK, page 58, 35V pp -> ADC input=  -1.75V -> I diode = 25mA, that's better. Still above Absolute Maximum Ratings
Rather than Input Protection, I would say "max input without damage"
 

Offline Mark_O

  • Frequent Contributor
  • **
  • Posts: 937
  • Country: us
Re: Hantek 6022BE 20MHz USB DSO
« Reply #536 on: March 31, 2014, 05:29:36 am »
Here are three versions of the schematic
pdf : http://jmp.sh/KDVL21k
bmp zipped : http://jmp.sh/gQ9MADv

No problem for me if you  use and modify this files. This is an Hantek's design.
Once nice thing about a schematic like this is it makes plain the fact that the 6022BE, unlike most scopes that have 3 or 4 decades of Sensitivity settings, has only one decade.  I.e., 100mV/div to 1V/div.  That's one area they saved money by compromising on (along with the limited sample rates, and no real triggering). [Normally, you see anywhere from 10 mV-5V/div, to 1 mV-10V/div.]

The settings below 100mV/div are just zoomed (e.g., like an Agilent with 4 mV/div claims 1 mV/div, by zooming).  Since at that level, the FS range of the ADC is 1,024 mV, and it's 8-bits (256 levels), that means the LSB is 4 mV.  So it's not surprising to see "noise" on the 20 mV/div setting, since in addition to real noise (that shielding and proper grounding can help minimize), the uncertainty present in the LSB will result in jitter of +/-4 mV, all by itself.  Which becomes more visible the farther in you zoom.

Not knocking it... just thinking out loud.
 

Offline Matchless

  • Regular Contributor
  • *
  • Posts: 119
  • Country: za
Re: Hantek 6022BE 20MHz USB DSO
« Reply #537 on: March 31, 2014, 03:22:28 pm »
Mark_O,
             I hope you don't mind if I add your last observations to the User Manual.

Thanks!
Regards
Matchless
 

Offline Mark_O

  • Frequent Contributor
  • **
  • Posts: 937
  • Country: us
Re: Hantek 6022BE 20MHz USB DSO
« Reply #538 on: March 31, 2014, 03:50:42 pm »
Mark_O,
             I hope you don't mind if I add your last observations to the User Manual.
Thanks!

Not at all.  Every instrument has some limitations.  The key is being aware of them, and understanding how they're still useful, and can provide valuable results. 

Hantek makes all this really opaque, which doesn't help (us) at all.  Ranging from claiming the device has 1M/channel, when it doesn't (the 1M is in your PC, and the device has only 1K/channel), to selectable sensitivity ranges that truncate well below a full-screen level, to pre/post-trigger point selection (in the specs) that flat-out don't exist.  Etc.  For someone to use the 6022BE effectively, they need not only quality software (which RichardK is providing), but also an understanding of the scope's true capabilities.  Many people here have helped contribute to that understanding.
 

Offline Matchless

  • Regular Contributor
  • *
  • Posts: 119
  • Country: za
Re: Hantek 6022BE 20MHz USB DSO
« Reply #539 on: April 01, 2014, 05:58:55 am »
Mark_O, thanks I have done so. I will post the latest copy of the user manual soon and if you do not mind please see if it looks correct, as I am sort of out of my comfort zone already!
I am waiting for RichardK's next update which should help me clear some of the parts in the manual in red at the moment.

Thanks again!
Regards
Matchless
 

Offline RichardK

  • Regular Contributor
  • *
  • Posts: 157
Re: Hantek 6022BE 20MHz USB DSO
« Reply #540 on: April 02, 2014, 06:31:24 pm »
Sorry about the delay between releases, been super busy of late.... Here is the latest binary... Not too many ground breaking changes, mostly just tying up loose ends and other bug fixes.

PR18 Download: http://jmp.sh/k0tTgXg

What's New:
-----------------------------------------------------------
1. Fixed a bug where not able to turn grid off in Phosphor mode.
2. Implemented simple waveform brightness support for 64bit operating systems.
3. Increased Output Window height so first measurement item is visible.
4. Implemented the Probe main menu items for CH1, CH2 and Math Channel.
5. Fixed a bug where a channel might not fully clear when changing to None in
   Demo Mode.
6. Changed Phase Offset units from Radians to Degrees.
7. Fixed an inconsistency in cursor over levers and dragging levers witch might
   cause a situation where a lever won't move even when the cursor changes
   suggesting you can.
8. Added an alternative rendering option in case AlphaBlend() fails, some 32 bit
   systems don't work well with AlphaBlend() apparently, especially in systems
   with multiple display configurations.
9. Reordered some Time Division menu items.
10. Added Dynamic option to Reference Channel's Function Generator (works like Demo Mode).
11. Implemented initial support of saving/restoring GUI settings on close/restart.
12. Increased Trigger Information render width to prevent voltages from rendering off
   screen.
13. Implemented hiding of Bottom Pane voltage labels when respective channel is hidden.
 
The following users thanked this post: mixiom

Offline Fraser

  • Super Contributor
  • ***
  • Posts: 9441
  • Country: gb
Re: Hantek 6022BE 20MHz USB DSO
« Reply #541 on: April 02, 2014, 06:38:24 pm »
No need for "Sorry".

Personally I am grateful for updates as and when you find any spare time to release such. We all have lives outside this forum and I understand that this is JUST a hobby project.

You have alreday put Hantek's original coders and ongoing software support team to shame !

Fraser
 

Offline Mark_O

  • Frequent Contributor
  • **
  • Posts: 937
  • Country: us
Re: Hantek 6022BE 20MHz USB DSO
« Reply #542 on: April 03, 2014, 12:10:09 am »
No need for "Sorry".

Personally I am grateful for updates as and when you find any spare time to release such. We all have lives outside this forum and I understand that this is JUST a hobby project.

You have already put Hantek's original coders and ongoing software support team to shame !

No kidding!  I'd be surprised if, over the years this product has been available, there has been more than 1 or 2 updates a year.  And those coming with little or no clue as to what had changed.

This is a really nice set of improvements.  Thanks.

Off the subject a bit:  One thing I'm not clear on, since I've never had to deal with it as a programmer, is how the screen draws vary between OS's, and 32/64-bit systems.  You've commented several times about AlphaBlend variations, and I don't really have a good picture of what's going on there?  I wouldn't expect you to write a book on it (that's probably already been done!), but a few line summary/overview might be helpful.
 

Offline RichardK

  • Regular Contributor
  • *
  • Posts: 157
Re: Hantek 6022BE 20MHz USB DSO
« Reply #543 on: April 03, 2014, 12:31:32 am »
No need for "Sorry".

Personally I am grateful for updates as and when you find any spare time to release such. We all have lives outside this forum and I understand that this is JUST a hobby project.

You have already put Hantek's original coders and ongoing software support team to shame !

No kidding!  I'd be surprised if, over the years this product has been available, there has been more than 1 or 2 updates a year.  And those coming with little or no clue as to what had changed.

This is a really nice set of improvements.  Thanks.

Off the subject a bit:  One thing I'm not clear on, since I've never had to deal with it as a programmer, is how the screen draws vary between OS's, and 32/64-bit systems.  You've commented several times about AlphaBlend variations, and I don't really have a good picture of what's going on there?  I wouldn't expect you to write a book on it (that's probably already been done!), but a few line summary/overview might be helpful.

AlphaBlend() is a windows GDI function that uses graphics hardware to do alpha channel blending (Transparencies and such), and a while back when XP first came out (And GDI AlphaBlend also came out) it wasn't too uncommon to come across hardware that didn't support Hardware Alpha Blending, but pretty much every graphics processing unit made today supports it, so you might think it would be odd for modern day systems to have issues with it, but alas they do.

It's not the hardware, it's Microsoft's AlphaBlend GDI function and it has all sorts of issues with 64 bit versions of Windows and other systems (32 or 64bit) that have non standard display configurations (Like dual displays)... Apparently Microsoft has been aware of these issues since Windows 7, and has officially stated that there is a bug, but have not fixed the issue or even addressed when a possible fix may be issued.  |O

I wasn't aware of all the fiasco's involved when I started using it for brightness effects (and eventually Phosphor mode)... You learn something new everyday I guess...
 

Offline pickle9000

  • Super Contributor
  • ***
  • Posts: 2152
  • Country: ca
Re: Hantek 6022BE 20MHz USB DSO
« Reply #544 on: April 03, 2014, 12:51:30 am »
 

Offline RichardK

  • Regular Contributor
  • *
  • Posts: 157
Re: Hantek 6022BE 20MHz USB DSO
« Reply #545 on: April 03, 2014, 03:05:48 am »
Hey Richard, remember this?

http://www.hantek.org/asken/iaskdetail.aspx?id=2014022803412937

Yeah... what about it? ... I see no replies *shocker*
 

Offline pickle9000

  • Super Contributor
  • ***
  • Posts: 2152
  • Country: ca
Re: Hantek 6022BE 20MHz USB DSO
« Reply #546 on: April 03, 2014, 03:37:58 am »
Only,  25 days 16 hours 9 ministes 15 seconds to go!!

I love the spelling "ministes", it would be fantastic if they come up with an answer. Unfortunately the answer will probably be that the manual was incorrect and this feature does not exist. 
 

Offline Mark_O

  • Frequent Contributor
  • **
  • Posts: 937
  • Country: us
Re: Hantek 6022BE 20MHz USB DSO
« Reply #547 on: April 03, 2014, 03:49:42 am »
AlphaBlend() is a windows GDI function that uses graphics hardware to do alpha channel blending (Transparencies and such), and a while back when XP first came out (And GDI AlphaBlend also came out) it wasn't too uncommon to come across hardware that didn't support Hardware Alpha Blending, but pretty much every graphics processing unit made today supports it, so you might think it would be odd for modern day systems to have issues with it, but alas they do.

It's not the hardware, it's Microsoft's AlphaBlend GDI function and it has all sorts of issues with 64 bit versions of Windows and other systems (32 or 64bit) that have non standard display configurations (Like dual displays)... Apparently Microsoft has been aware of these issues since Windows 7, and has officially stated that there is a bug, but have not fixed the issue or even addressed when a possible fix may be issued.  |O

I wasn't aware of all the fiasco's involved when I started using it for brightness effects (and eventually Phosphor mode)... You learn something new everyday I guess...

Thanks for the education, Richard.  Yes, any of us who've had to deal with MS API's over the years can feel the pain.
 

Offline Mark_O

  • Frequent Contributor
  • **
  • Posts: 937
  • Country: us
Re: Hantek 6022BE 20MHz USB DSO
« Reply #548 on: April 03, 2014, 03:54:02 am »
Hey Richard, remember this?

http://www.hantek.org/asken/iaskdetail.aspx?id=2014022803412937

Yeah... what about it? ... I see no replies *shocker*

Well, in fairness to them, the title IS "Go Ask Hantek".  No claim is made that they will bother to answer.   :-[
 

Offline Bocks

  • Newbie
  • Posts: 4
Re: Hantek 6022BE 20MHz USB DSO
« Reply #549 on: April 03, 2014, 03:59:26 am »
8. Added an alternative rendering option in case AlphaBlend() fails, some 32 bit
   systems don't work well with AlphaBlend() apparently, especially in systems
   with multiple display configurations.

Works great on my dual monitor setup. Thanks!
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf