EEVblog #1038 - Uni T UPO2104CS Oscilloscope Teardown

[EEVblog]

What's inside the 4CH 100200MHz entry level Uni-T UPO2104CS oscilloscope?

[ataradov]

Video went down?

[technix]

Why is there 20 seconds of dead air between 2:35 and 2:55?

[chriswebb]

The display artifacts were because the gradient was using black on the low range. When you made it one color, you saw that it was the signal and not a bug in the display.

[OzOnE]

@technix

Haha - I KNEW Dave couldn't let that go.

(may have been some other missing sections maybe?)

Looks like he's re-uploading the vid, and just when I was about to post an "amusing" comment. lol

Interestingly, I could still watch a fair bit of the vid as it was cached, but I made the mistake of refreshing, thinking that the error while posting the comment was a networking issue.

Oh well. I'll await the re-upload.

OzOnE

[ataradov]

It was not a mistake, I was just watching the video and it just abruptly stopped anyway.

[OzOnE]

Do you mean it stopped before the end anyway?

Ahh, OK. Just a rendering glitch then. No biggie.

OzOnE.

[ataradov]

Do you mean it stopped before the end anyway?

Yep, stopped mid sentence, and static, and "Video is no longer available" or something like that.

[OzOnE]

Yep, that's where Mr Dave is likely re-uploading.

OzOnE.

[nidlaX]

Good to finally see a teardown of this scope, I recall there was a lot of speculation over its capabilities and OEM when it was released.

[iceisfun]

Are the function lockout messages at the end because independent time bases are enabled?

[EEVblog]

Are the function lockout messages at the end because independent time bases are enabled?

Yes, you can't turn off any of the channels with the ind timebase enabled.

[snoopy]

You can see it here

https://www.bitchute.com/video/GIKrPcdRxYM/

[EEVblog]

Fixed video is now back up.
Took a while, had to come back into the office after dinner and re-render.

[ChrisLX200]

Thanks for the great review! I think at that price point I would wait to see the Siglent offering though. Did I see a date of April 2017 on your example? Maybe Uni-T already fixed some of the display issues you noted, but even so, too expensive to compete I think.

[tzok]

Are the function lockout messages at the end because independent time bases are enabled?

Yes, you can't turn off any of the channels with the ind timebase enabled.

I think he meant the Function Disabled for Decode due to Independent Mode enabled.

[tszaboo]

Dave, you call a bunch of resitors around 10:50 termination resistors.  I would've guessed they are for configuration. First, only 1 of each pair is on the board. Also, all of them are 01C = 10KOhm. Maybe this scope can be hacked for higher speed/more memory very easily??

[Ondre]

I saw that UNI-T is using thermal reliefs on the vias. Is there a good reason to do so? I usually connect them directly to the plane, unless I plan to solder bodge wires to them :-)

[don.r]

If you do a shootout, please include the Micsig in there.

[NivagSwerdna]

Too many bodges for me.  UniT won't be on my Christmas list.  (Nice sqiggles though)

[Hydron]

Hi Dave,

The Analog Devices "DAC" part you found is actually an ADCMP562B (i.e. the bit after ADCMP looks similar to 5628). This is a "Dual High Speed PECL Comparator", which makes sense for a trigger section.

Thanks for the teardown, always interesting to see how they've spent their money in low cost stuff like this.

Edit: regarding the channel bias, my RTB2004 has a "Zero Offset" control in the vertical menu, which seems to do the same thing. I've found it handy a couple of times dealing with active probes with (small) output offsets - no idea of the range of the control.

[smashIt]

I'd guess that the "bodge" at minute 20 is just a flipped resistor.

[Someone]

Same as the GW Instek GDS-1000B the power supply earthing connection (and other aspects of the mains wiring) don't meet Australian basic safety standards from AS3100, and would fail other regions standards too. No wonder you don't find many sellers for it.

[nctnico]

Edit: regarding the channel bias, my RTB2004 has a "Zero Offset" control in the vertical menu, which seems to do the same thing. I've found it handy a couple of times dealing with active probes with (small) output offsets - no idea of the range of the control.

I've also found a bias control in a Yokogawa DSO but in the end it it controlled the same DAC as the trace offset.

[kcozens]

We know that Bob's your uncle but who is this Flynn person?    The two DDR memory chips were upside down. I was waiting for you to point out the electrons are going to fall out.

The UNI-T has better colour choices for the four traces vs the colours used by the Rigol 1054Z. I wonder if the 50 second boot time is due to the UNI-T possibly running a version of Windows based on it having a PrtScr button. For proper price comparison you have to look at the Rigol 1104Z. It has a price of $619 for the Rigol 1104Z so the UNI-T is only $20 less. The Rigol 1054Z wins on price if a user hacks the scope to enable its full capabilities. Have you hit the Display button to see if it has the XY display mode?