Author Topic: EEVBlog 121GW Discussion thread  (Read 108327 times)

0 Members and 2 Guests are viewing this topic.

Offline EEVblog

  • Administrator
  • *****
  • Posts: 26641
  • Country: au
    • EEVblog
Re: EEVBlog 121GW Discussion thread
« Reply #425 on: March 08, 2018, 12:09:56 am »
The 24 hour video was no longer listed when I checked, so yes I was referring to your how-to video.   

Youtube is rooted, it's there.



It's still processing

 

Offline idpromnut

  • Supporter
  • ****
  • Posts: 613
  • Country: ca
Re: EEVBlog 121GW Discussion thread
« Reply #426 on: March 08, 2018, 12:49:39 am »
@Dave: at the risk of sounding like an ungrateful asshole, while the beeper on/off option is fantastic (nice and quite now!  :-+ ), it renders the continuity beeper also silent, which I would argue either should have it's own configuration option, or at least be on all the time, even if the beeper for functions/buttons is turned off.

That being said, I don't know that I would classify this as an "issue".  A big thanks to UEi for getting issues in the FW addressed quickly!
 
The following users thanked this post: Average Meatsack

Offline Candid

  • Regular Contributor
  • *
  • Posts: 128
  • Country: de
Re: EEVBlog 121GW Discussion thread
« Reply #427 on: March 08, 2018, 01:26:10 am »
Maybe someone can explain to me what the problem is:
2 different function generators tested, JDS6600 and FeelTech FY6600. Identical settings, identical results.

For example: 4kHz square wave with 2.0Vpp. Measured Vac with the 121GW and as comparison a Fluke 28II (highres mode).

Range AUTO: 121GW selects 5V range, Fluke selects 6V range
121GW reads 1.37xxVac, Fluke reads 0.99xxVac

Manual range 5V 121GW, 6V Fluke 28II:
121GW reads 1.37xxVac, Fluke reads 0.99xxVac

Manual range 50V 121GW, 60V Fluke 28II:
121GW reads 0.95xVac, Fluke reads 0.94xxVac

Similar behavior for the 121GW with sine wave. It reads 1,117xV in auto range and manual 5V range and 0,664V in manual 50V range. I checked with 200Hz sine and same behavior for the 121GW, Fluke and Brymen 235 work fine.

What is the 121GW doing in auto range / 5V range?


And Bluetooth:
Still the same for me. It's more or less luck if I get a connection to the meter. Tried both apps. When I get a connection with Dave2-App I only get something displayed in the lower half of the display, the upper half stays completely blank for me on my Samsung Galaxy S8.
« Last Edit: March 09, 2018, 10:51:04 pm by Candid »
 
The following users thanked this post: Iagash

Offline Iagash

  • Regular Contributor
  • *
  • Posts: 69
  • Country: de
Re: EEVBlog 121GW Discussion thread
« Reply #428 on: March 08, 2018, 01:27:48 am »
@Dave: at the risk of sounding like an ungrateful asshole, while the beeper on/off option is fantastic (nice and quite now!  :-+ ), it renders the continuity beeper also silent, which I would argue either should have it's own configuration option, or at least be on all the time, even if the beeper for functions/buttons is turned off.

That being said, I don't know that I would classify this as an "issue".  A big thanks to UEi for getting issues in the FW addressed quickly!

On first thought I'd also say that the continuity beep should be always on. But on second thought it's maybe a matter of taste.

A bonus would be a blinking backlight if the continuity beep is off.

Anyways thanks for the beeper option.
 

Offline Hydron

  • Frequent Contributor
  • **
  • Posts: 280
  • Country: gb
Re: EEVBlog 121GW Discussion thread
« Reply #429 on: March 08, 2018, 02:29:44 am »
 I personally think the beeper is necessary in the following circumstances:
- Continuity (which even uses the sound symbol!)
- Diode test
- When you've been an idiot and left a probe in the A jack when the meter is in voltage mode (assuming it's using sensing jacks - can't remember if this is the case)
- Over-load warning on ranges where an overload could cause damage

Other than those, I'd normally want the beeper off, so I'd agree with everyone asking for a middle option (preferably as a third setting in addition to the current two)
 

Online joeqsmith

  • Super Contributor
  • ***
  • Posts: 4719
  • Country: us
Re: EEVBlog 121GW Discussion thread
« Reply #430 on: March 08, 2018, 05:47:35 am »
Maybe someone can explain to me what the problem is:
2 different function generators tested, JDS6600 and FeelTech FY6600. Identical settings, identical results.

I do not have a released version of the meter.  Plus I damaged this one a few times, modified it and its running the original firmware.  Yet for some strange reason, it does not behave the same as yours.     :-DD   It sounds like they actually addressed a problem with the prototype so thanks for running this test!
How electrically robust is your meter?? http://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 
The following users thanked this post: jancumps

Offline EEVblog

  • Administrator
  • *****
  • Posts: 26641
  • Country: au
    • EEVblog
Re: EEVBlog 121GW Discussion thread
« Reply #431 on: March 08, 2018, 11:24:22 am »
Bluetooth and VA mode is still completely broken, even if you filter the invalid records.
It's also broken in the android app. It displays the same wrong readings.

The 391.2 mVA reading is the correct one.

I can confirm this, I see infrequent large scale data value excursion in VA mode. Reported.
 

Online mtdoc

  • Super Contributor
  • ***
  • Posts: 3439
  • Country: us
Re: EEVBlog 121GW Discussion thread
« Reply #432 on: March 08, 2018, 12:13:06 pm »
I personally think the beeper is necessary in the following circumstances:
- Continuity (which even uses the sound symbol!)
- Diode test
- When you've been an idiot and left a probe in the A jack when the meter is in voltage mode (assuming it's using sensing jacks - can't remember if this is the case)
- Over-load warning on ranges where an overload could cause damage

Other than those, I'd normally want the beeper off, so I'd agree with everyone asking for a middle option (preferably as a third setting in addition to the current two)

I agree. That seems like a no brainer.
 

Offline Seppy

  • Administrator
  • *****
  • Posts: 157
  • Country: au
  • Curious
Re: EEVBlog 121GW Discussion thread
« Reply #433 on: March 09, 2018, 02:27:22 pm »
a) Nothing was "removed in editing". The entire original 23 hour video is still being processed by youtube and will eventually be available online. It seems that only the final 2 hours is currently available.

b) By the "edited video" I presume you mean the one "How to do Lifecycle Testing". I simply extracted some content from the stream to create a new video were I talked about general range switch testing as I thought it might be interesting to people as separate video.

c) There is a uCurrent x100 amplifier used in the jig across the switch contacts, that is not shown in the equations.

The 24 hour video was no longer listed when I checked, so yes I was referring to your how-to video.   

Quote
.. r=v/2300 and R=2740/((1/r)-1) . The second note stated the first column was V.    So for v=128,  R=2740/((2300/128)-1) = 152.5. 

I assume it's not as simple as it being off by 100X or 0.152 ohms,  seems way too low but maybe.     Looking at V=1272, R = 1.516 in this case and I think it was much higher.  Strange that the basics are not clear or just coded.



There is a 100x amplifier, that formula didn't show the uCurrent gain.
 

Offline Seppy

  • Administrator
  • *****
  • Posts: 157
  • Country: au
  • Curious
Re: EEVBlog 121GW Discussion thread
« Reply #434 on: March 09, 2018, 02:43:12 pm »
Maybe someone can explain to me what the problem is:
2 different function generators tested, JDS6600 and FeelTech FY6600. Identical settings, identical results.

For example: 4kHz SQRT with 2Vpp. Measured ACV with the 121GW and as comparison a Fluke 28II (highres mode).

Range AUTO: 121GW selects 5V range, Fluke selects 6V range
121GW reads 1,37xxVac, Fluke reads 0,99xxVac

Manual range 5V 121GW, 6V Fluke 28II:
121GW reads 1,37xxVac, Fluke reads 0,99xxVac

Manual range 50V 121GW, 60V Fluke 28II:
121GW reads 0,95xVac, Fluke reads 0,94xxVac

Did you mean 2V peak to peak square wave, what did you mean by square root (SQRT)?
I reproduced the test and do not get your results. I get 1.0022 Vrms on a production meter for the above setup.

Did you signal generator have a DC offset, if so make sure that the 121GW isn't in DC + AC mode.
DC + AC mode for a 0 - 2V square wave results in approximately 1.4V, which is close to what you measured.

« Last Edit: March 09, 2018, 02:50:23 pm by Seppy »
 

Offline Candid

  • Regular Contributor
  • *
  • Posts: 128
  • Country: de
Re: EEVBlog 121GW Discussion thread
« Reply #435 on: March 09, 2018, 11:24:58 pm »
Sorry, my mistake. square wave for sure.

Can you reproduce the following measurements?
2.0V peak to peak sine wave 4kHz, No DC offset, duty cycle 50%. Both meters in AC mode. Firmware 1.07 on my 121GW with serial number EEVblog 000084

Auto mode on both meters, Fluke in highres mode:
121GW selects 5V range, reads 1.1133Vac
Fluke 28II selects 6V range, reads 0.7031Vac

manual mode on both meters:
121GW 5V range, reads 1.1133Vac
Fluke 28II 6V range, 0.7032Vac

121GW 50V range, reads 0.659Vac (and it looses the frequency measurement and displays 0.00kHz)
Fluke 28II 60V range, reads 0.663Vac

See the attached pictures.
« Last Edit: March 09, 2018, 11:27:19 pm by Candid »
 

Offline fanOfeeDIY

  • Supporter
  • ****
  • Posts: 297
  • Country: jp
    • YouTube Channel
Re: EEVBlog 121GW Discussion thread
« Reply #436 on: March 12, 2018, 08:52:36 am »
I uploaded video regarding roughly comparing Burden Voltage.

 

Online joeqsmith

  • Super Contributor
  • ***
  • Posts: 4719
  • Country: us
Re: EEVBlog 121GW Discussion thread
« Reply #437 on: March 12, 2018, 10:01:21 am »
I uploaded video regarding roughly comparing Burden Voltage.

Quote
On your 121GW, you do have a fairly high resolution. In the Amps low range, I think its 10uA resolution which is what you have with the other meters. However, your burden voltage is to be VERY low. Maybe 200ish uv!! Try that and see what you think.? 

I posted the above comment on YT.   Looking in the manual, maybe it no longer works this but I'm pretty sure that the prototype did.   
How electrically robust is your meter?? http://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline EEVblog

  • Administrator
  • *****
  • Posts: 26641
  • Country: au
    • EEVblog
Re: EEVBlog 121GW Discussion thread
« Reply #438 on: March 12, 2018, 10:26:42 am »
I uploaded video regarding roughly comparing Burden Voltage.

Quote
On your 121GW, you do have a fairly high resolution. In the Amps low range, I think its 10uA resolution which is what you have with the other meters. However, your burden voltage is to be VERY low. Maybe 200ish uv!! Try that and see what you think.? 

I posted the above comment on YT.   Looking in the manual, maybe it no longer works this but I'm pretty sure that the prototype did.

The 500mA range uses the Amps jack (and a x10 amplifier) unlike most meters. This gives a very low maximum burden voltage of 30mV/A, or 15mV for 500mA full scale.
Very few meters will be this low on the 500mA range.
With 50,000 count the resolution is 10uA.
 

Online joeqsmith

  • Super Contributor
  • ***
  • Posts: 4719
  • Country: us
Re: EEVBlog 121GW Discussion thread
« Reply #439 on: March 12, 2018, 10:57:44 am »
I uploaded video regarding roughly comparing Burden Voltage.

Quote
On your 121GW, you do have a fairly high resolution. In the Amps low range, I think its 10uA resolution which is what you have with the other meters. However, your burden voltage is to be VERY low. Maybe 200ish uv!! Try that and see what you think.? 

I posted the above comment on YT.   Looking in the manual, maybe it no longer works this but I'm pretty sure that the prototype did.

The 500mA range uses the Amps jack (and a x10 amplifier) unlike most meters. This gives a very low maximum burden voltage of 30mV/A, or 15mV for 500mA full scale.
Very few meters will be this low on the 500mA range.
With 50,000 count the resolution is 10uA.
Thanks.   

I had DL'ed the manual when you made it available.  The one I have is 25th Nov. 17.   I see a mention of the 500mA mode on page 11. 

Quote
A and 500mA    11A/1000V DC/AC, IR 20kA HRC FAST + DIODE
and again on page 55
Quote
A/500mA current input fuse: 11A/1000V DC/AC, IR 20kA HRC FAST

The table on page 14 does not mention it.   
Quote
The following modes will use the x10 amplifier and may have additional off-set error that can be nulled out before measurement.

Maybe add something to page 32 where the current measurement is shown.   When I looked at the burden on the pre-production, is was pretty impressive.  From fanOfeeDIY's video, the manual may need a few small additions. 

Maybe you (Dave) would consider making a short video showing the meter's burden compared to a few others and how to use it properly.     
How electrically robust is your meter?? http://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline fanOfeeDIY

  • Supporter
  • ****
  • Posts: 297
  • Country: jp
    • YouTube Channel
Re: EEVBlog 121GW Discussion thread
« Reply #440 on: March 12, 2018, 11:15:47 am »
I uploaded video regarding roughly comparing Burden Voltage.

Quote
On your 121GW, you do have a fairly high resolution. In the Amps low range, I think its 10uA resolution which is what you have with the other meters. However, your burden voltage is to be VERY low. Maybe 200ish uv!! Try that and see what you think.? 

I posted the above comment on YT.   Looking in the manual, maybe it no longer works this but I'm pretty sure that the prototype did.

The 500mA range uses the Amps jack (and a x10 amplifier) unlike most meters. This gives a very low maximum burden voltage of 30mV/A, or 15mV for 500mA full scale.
Very few meters will be this low on the 500mA range.
With 50,000 count the resolution is 10uA.
Thanks.   

I had DL'ed the manual when you made it available.  The one I have is 25th Nov. 17.   I see a mention of the 500mA mode on page 11. 

Quote
A and 500mA    11A/1000V DC/AC, IR 20kA HRC FAST + DIODE
and again on page 55
Quote
A/500mA current input fuse: 11A/1000V DC/AC, IR 20kA HRC FAST

The table on page 14 does not mention it.   
Quote
The following modes will use the x10 amplifier and may have additional off-set error that can be nulled out before measurement.

Maybe add something to page 32 where the current measurement is shown.   When I looked at the burden on the pre-production, is was pretty impressive.  From fanOfeeDIY's video, the manual may need a few small additions. 

Maybe you (Dave) would consider making a short video showing the meter's burden compared to a few others and how to use it properly.   

I am not quite following the discussion.  :'(
Especially "200ish uv!!" part.
Should I have used different range in my video?

 

Online joeqsmith

  • Super Contributor
  • ***
  • Posts: 4719
  • Country: us
Re: EEVBlog 121GW Discussion thread
« Reply #441 on: March 12, 2018, 11:34:26 am »
I am not quite following the discussion.  :'(
Especially "200ish uv!!" part.
Should I have used different range in my video?

Do the same test with your 121GW except attach the leads from the A 500mA connector and the COM.   The 121GW will display the current with a resolution of 10uA just like the others you show.  However, now if you look at the burden voltage for the meter, I suspect you will see something around 200uV  rather then several mV as your video shows.   I use "ish" as close enough.   

I had modified a UNI-T UT61E which has a very high burden voltage, in an attempt to improve it.   There was only so much I could do in the area available and the way the board was laid out.  I think are real low current, the burden on this meter was lower than the 121GW but once I changed ranged, it was very clear just how good the 121GW was.   It's impressive.   Give it a try and see what happens.  Post your updates, text is good enough. 
How electrically robust is your meter?? http://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline fanOfeeDIY

  • Supporter
  • ****
  • Posts: 297
  • Country: jp
    • YouTube Channel
EEVBlog 121GW Discussion thread
« Reply #442 on: March 12, 2018, 11:44:13 am »
I am not quite following the discussion. 
Especially "200ish uv!!" part.
Should I have used different range in my video?

Do the same test with your 121GW except attach the leads from the A 500mA connector and the COM.   The 121GW will display the current with a resolution of 10uA just like the others you show.  However, now if you look at the burden voltage for the meter, I suspect you will see something around 200uV  rather then several mV as your video shows.   I use "ish" as close enough.   

I had modified a UNI-T UT61E which has a very high burden voltage, in an attempt to improve it.   There was only so much I could do in the area available and the way the board was laid out.  I think are real low current, the burden on this meter was lower than the 121GW but once I changed ranged, it was very clear just how good the 121GW was.   It's impressive.   Give it a try and see what happens.  Post your updates, text is good enough.

Ah, I completely understood now.

Let me take and upload a short video tonight as your advice with A/500mA connector.
I still have the setup on my desk.
« Last Edit: March 12, 2018, 11:57:57 am by fanOfeeDIY »
 

Offline fanOfeeDIY

  • Supporter
  • ****
  • Posts: 297
  • Country: jp
    • YouTube Channel
Re: EEVBlog 121GW Discussion thread
« Reply #443 on: March 12, 2018, 09:31:45 pm »
I am not quite following the discussion.  :'(
Especially "200ish uv!!" part.
Should I have used different range in my video?

Do the same test with your 121GW except attach the leads from the A 500mA connector and the COM.   The 121GW will display the current with a resolution of 10uA just like the others you show.  However, now if you look at the burden voltage for the meter, I suspect you will see something around 200uV  rather then several mV as your video shows.   I use "ish" as close enough.   

I had modified a UNI-T UT61E which has a very high burden voltage, in an attempt to improve it.   There was only so much I could do in the area available and the way the board was laid out.  I think are real low current, the burden on this meter was lower than the 121GW but once I changed ranged, it was very clear just how good the 121GW was.   It's impressive.   Give it a try and see what happens.  Post your updates, text is good enough.

Thank you for your valuable comment on both YouTube and here.
I uploaded another video.
 
The following users thanked this post: rodcastler, Cliff Matthews, 1anX, genghisnico13

Offline EEVblog

  • Administrator
  • *****
  • Posts: 26641
  • Country: au
    • EEVblog
Re: EEVBlog 121GW Discussion thread
« Reply #444 on: March 12, 2018, 09:50:59 pm »
Maybe add something to page 32 where the current measurement is shown.   When I looked at the burden on the pre-production, is was pretty impressive.  From fanOfeeDIY's video, the manual may need a few small additions. 

Yep, the manual needs some updating.
The burden voltage may not be much better than, or on par with some other meters depending upon the range selected. It's a combination of what range uses the x10 amplifier and what shunt is used.
You could get the same excellent burden voltage on every range, but you'd need a effectively manual range switch positions with an optimised shunt for every range.
Very few meters will use the A jack for the 500mA range, so if your needs are on that range, it's going to be hard to beat.
 

Online joeqsmith

  • Super Contributor
  • ***
  • Posts: 4719
  • Country: us
Re: EEVBlog 121GW Discussion thread
« Reply #445 on: March 12, 2018, 10:07:20 pm »
Thank you for your valuable comment on both YouTube and here.
I uploaded another video.
Thank you for taking the time to run the test a second time. 
How electrically robust is your meter?? http://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline EEVblog

  • Administrator
  • *****
  • Posts: 26641
  • Country: au
    • EEVblog
Re: EEVBlog 121GW Discussion thread
« Reply #446 on: March 14, 2018, 09:50:39 am »
V1.09 firmware https://www.eevblog.com/wp-content/uploads/2017/11/EEVBlog1_09.zip
It fixes the issue with the VA mode Bluetooth connection sending garbage data.

 
The following users thanked this post: VK5RC, haoleboy, Candid, ChrisG, 1anX

Offline dcac

  • Regular Contributor
  • *
  • Posts: 117
Re: EEVBlog 121GW Discussion thread
« Reply #447 on: March 14, 2018, 11:31:06 pm »
I am not quite following the discussion.  :'(
Especially "200ish uv!!" part.
Should I have used different range in my video?

Do the same test with your 121GW except attach the leads from the A 500mA connector and the COM.   The 121GW will display the current with a resolution of 10uA just like the others you show.  However, now if you look at the burden voltage for the meter, I suspect you will see something around 200uV  rather then several mV as your video shows.   I use "ish" as close enough.   

I had modified a UNI-T UT61E which has a very high burden voltage, in an attempt to improve it.   There was only so much I could do in the area available and the way the board was laid out.  I think are real low current, the burden on this meter was lower than the 121GW but once I changed ranged, it was very clear just how good the 121GW was.   It's impressive.   Give it a try and see what happens.  Post your updates, text is good enough.

Thank you for your valuable comment on both YouTube and here.
I uploaded another video.


Is the 121GW current measurement really within spec. here, it seems to show something like 4.6000mA when using the mA/uA jack but using the 10A jack it shows about 4.23mA - seems quite a bit of to me.

 

Offline ChrisG

  • Supporter
  • ****
  • Posts: 106
  • Country: nl
Re: EEVBlog 121GW Discussion thread
« Reply #448 on: March 15, 2018, 07:04:03 am »
The beeping beeper is a bit funny indeed now. When switched off it does not beep at all, whilst the beeper icon is showing still. So agree and concur with the others. Suggestion for the Manual: make clear that the bin file needs to be named EEVblog.bin exactly. When I used the EEVblog1.09.bin file name it did not work, waited for 5 minutes and then decided to abort.
 

Offline Iagash

  • Regular Contributor
  • *
  • Posts: 69
  • Country: de
Re: EEVBlog 121GW Discussion thread
« Reply #449 on: March 16, 2018, 03:54:40 am »
V1.09 firmware https://www.eevblog.com/wp-content/uploads/2017/11/EEVBlog1_09.zip
It fixes the issue with the VA mode Bluetooth connection sending garbage data.

Not really, the main display is correct now, but the upper display lost any connection to reality.

The corrupted data records are still there but less frequent.

 :palm:
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf