New TRMS Uni-T UT139C DMM is available now

[Kbird]

Thanks Total Noob , I do know MJLorton's Website , so I will have a look there for sure , it is possible there are just functions etc of this meter my old POS DMM doesn't have and I am doing something wrong , it's why I upgraded , it doesn't even have a continuity setting (or buzzer) and I wanted to play around with Arduino etc as well as Household Repairs etc.



https://www.youtube.com/user/mjlorton

[Shadowjump]

I just got it today. Is there any way to keep the backlight on? It turns off so fast that there is no point in turning it on.

[Kbird]

I just got it today. Is there any way to keep the backlight on? It turns off so fast that there is no point in turning it on.

I just got one too and think 15 secs is too short as well, but the only fix for it is if you are willing to hack the Firmware on the DMM Chip , it has been done by many, more savvy than me though   see Kerry Wong's Page about it here..... you don't need to do the whole hack just for the backlight ie adding the IR receiver/sender etc you just need to change the hex file correct and upload it to the chip. you can apparently make it a 8000 or 9000 count meter too.

http://www.kerrywong.com/2016/03/19/hacking-dtm0660l-based-multimeters/

The audible chirp when using the dial can't be fixed ( needed for continuity buzzer too) but it doesn't bother me like some, I did see a post saying to add some hot glue to the sensor/speaker to lower the volume works though.

KB

[Martini]

I just got it today. Is there any way to keep the backlight on? It turns off so fast that there is no point in turning it on.

I just got one too and think 15 secs is too short as well, but the only fix for it is if you are willing to hack the Firmware on the DMM Chip , it has been done by many, more savvy than me though   see Kerry Wong's Page about it here..... you don't need to do the whole hack just for the backlight ie adding the IR receiver/sender etc you just need to change the hex file correct and upload it to the chip. you can apparently make it a 8000 or 9000 count meter too.

http://www.kerrywong.com/2016/03/19/hacking-dtm0660l-based-multimeters/

Great!

The audible chirp when using the dial can't be fixed

Sad.

[Kbird]

I just got it today. Is there any way to keep the backlight on? It turns off so fast that there is no point in turning it on.

I just got one too and think 15 secs is too short as well, but the only fix for it is if you are willing to hack the Firmware on the DMM Chip , it has been done by many, more savvy than me though   see Kerry Wong's Page about it here..... you don't need to do the whole hack just for the backlight ie adding the IR receiver/sender etc you just need to change the hex file correct and upload it to the chip. you can apparently make it a 8000 or 9000 count meter too.

http://www.kerrywong.com/2016/03/19/hacking-dtm0660l-based-multimeters/

Great!

The audible chirp when using the dial can't be fixed

Sad.

I did end up modding my 139C , with the Help of FrozenFrog over on this thread....

https://www.eevblog.com/forum/testgear/uni-t-ut139c-lcd-biasing-(schematics-avail)/msg1165035/#msg1165035

KB

[darmach]

Guys, I'm looking for a new mmeter - this or Uni-t UT61D? Why?

Im interested in precision, reliability and speed .)

I can also buy an used Metex M-3850D similar price, maybe that?

[Kbird]

Guys, I'm looking for a new mmeter - this or Uni-t UT61D? Why?

Im interested in precision, reliability and speed .)

I can also buy an used Metex M-3850D similar price, maybe that?

I am no expert on MMeters ( or electronics)  but I returned my 61E ( getting stuck in autorange it seemed) and got the 139C ( safer for mains voltage which I wanted) and am happy with it so far, and recently picked up the UT-210E mini Clamp meter to complement it too. And I have now hacked both based on posts here (and elsewhere) to add/change a few features.

more info on that here https://www.eevblog.com/forum/testgear/a-look-at-the-uni-t-ut210e/
and
https://www.eevblog.com/forum/testgear/uni-t-ut139c-lcd-biasing-(schematics-avail)/new/?topicseen#new

[darmach]

Guys, I'm looking for a new mmeter - this or Uni-t UT61D? Why?

Im interested in precision, reliability and speed .)

I can also buy an used Metex M-3850D similar price, maybe that?

I am no expert on MMeters ( or electronics)  but I returned my 61E ( getting stuck in autorange it seemed) and got the 139C ( safer for mains voltage which I wanted) and am happy with it so far, and recently picked up the UT-210E mini Clamp meter to complement it too. And I have now hacked both based on posts here (and elsewhere) to add/change a few features.

more info on that here https://www.eevblog.com/forum/testgear/a-look-at-the-uni-t-ut210e/
and
https://www.eevblog.com/forum/testgear/uni-t-ut139c-lcd-biasing-(schematics-avail)/new/?topicseen#new

And how do you felt the quality, and working with them? Which one seem to be faster, more convenient?

[Kbird]

Guys, I'm looking for a new mmeter - this or Uni-t UT61D? Why?

Im interested in precision, reliability and speed .)

I can also buy an used Metex M-3850D similar price, maybe that?

I am no expert on MMeters ( or electronics)  but I returned my 61E ( getting stuck in autorange it seemed) and got the 139C ( safer for mains voltage which I wanted) and am happy with it so far, and recently picked up the UT-210E mini Clamp meter to complement it too. And I have now hacked both based on posts here (and elsewhere) to add/change a few features.

more info on that here https://www.eevblog.com/forum/testgear/a-look-at-the-uni-t-ut210e/
and
https://www.eevblog.com/forum/testgear/uni-t-ut139c-lcd-biasing-(schematics-avail)/new/?topicseen#new

And how do you felt the quality, and working with them? Which one seem to be faster, more convenient?

I did not have the 61E long but they seem about the same from what I remember , I am happy with the 139C , i have used it alot on the Bench , modifying so old Gameport Joysticks and throttles to USB and messing with Arduino etc and also at Work to check Voltages and Temperature to which was handy.

the 210E wouldn't be a good Bench MMeter, but is handy if you work on Vehicles etc too or want to check Appliances etc with the Clamp .

I don't know the Metex at all , perhaps some-else will post about that, perhaps it's a good buy ? though if you need Data logging it and the 61E are the only two to do it. there is an old post on that meter from 2013 I just found here :

https://www.eevblog.com/forum/testgear/metex-m-3850-dmm-good/

If you want a cheaper meter ($20-25) to play with or as a backup to your main MMeter , there is alot of talk about the AN8008 in this thread :
https://www.eevblog.com/forum/testgear/an8008-us-$19-10000count-1uv-0-01ua-0-01ohm-resolution-meter/



 

[MosherIV]

Guys, I'm looking for a new mmeter - this or Uni-t UT61D? Why?

Im interested in precision, reliability and speed .)

Go with the UT139 for your new meter.

If you truely are after precision, you should be looking much more up market - 4 digit meters and above. Now you are into bench meter territory, which generally are not as reobust as the hand helds.

Also, precision and speed do not generally go together. You either want precisionand accuracy and are prepared to wait for the measurement (though now a days they take 10+ measurements a second) or you want speed and sacrifice precision/accuracy.

[darmach]

Guys, I'm looking for a new mmeter - this or Uni-t UT61D? Why?

Im interested in precision, reliability and speed .)

Go with the UT139 for your new meter.

If you truely are after precision, you should be looking much more up market - 4 digit meters and above. Now you are into bench meter territory, which generally are not as reobust as the hand helds.

Also, precision and speed do not generally go together. You either want precisionand accuracy and are prepared to wait for the measurement (though now a days they take 10+ measurements a second) or you want speed and sacrifice precision/accuracy.

Ah, that's a very good advice. Most likely I wanted a holy grail then! .) Thank you!

[darmach]

Oh and the most important things autoranging is slow, in resistance, like with UT-61D but Continuity beeper is super fast.
Binding posts are solid type and feel really good, much better than with my UT-61D/E. I have all three meters so I can do comparison.
Manual quotes screen updates 2-3 times per second, looks faster than UT-61D, but doesn't have that analog bar graph thing.
Max min includes Max-Min, so it shows difference.

EDIT: Few bits... that oscillator is soldered from its can to the board. Case is held by two self tappers, battery cover with the fuse inside is held by machine screw into metal insert.

More: microamps range resistance 101 ohms, milliamps 2,1 ohms, amps less than 0,10 ohms, amps range is really tricky to measure.  All measured with UT61E with probes relatived out.
 for UT61D those are microamps 50 ohms, milliamps ~0.8 ohms (I think dave also has covered ut61d in his 100$ MM shootout)

One more thing to point out, probes are super dull compared to normal uni-t 61d/e probes

Please check the gallery for more pictures: http://imgur.com/a/984K7/all

What else should I test with this meter? I don't have any accurate references, but I can do comparative measurements since I doubt all three of my Uni-t meter are out of cal.

Hi, you wrote that you have both ut139c and ut61E. Can you compare autoranging speed between them? Measurement speed? I'm torn between these two.

[hans_ober]

Was considering purchasing this meter based on all the reviews I've read. I'm an EE student, and will use it for hobbyist electronics work, plus electrical work around the house (and fixing electrical stuff).

I was looking for an Autoranging True RMS meter in general. Most often used functions would be Voltage and Continuity test (which is fast on the 139C from what I've read). Backlight and Temperature weren't essential, but nice to have.

I'd like a Peak/ Min-Max mode that I could use to calculate the Crest/Peak factor of AC Mains voltage.

What's the difference between the Peak function on the UT-61E and the Min/Max on the 139C?

Will the Min/Max on the 139C show me the peak of a sine wave: 230 * 1.414 = ~320V (assuming a crest factor of 1.414 for a perfect sine wave)?

[Martini]

What's the difference between the Peak function on the UT-61E and the Min/Max on the 139C?

Will the Min/Max on the 139C show me the peak of a sine wave: 230 * 1.414 = ~320V (assuming a crest factor of 1.414 for a perfect sine wave)?

No. It will display 0V or close.




EDIT: I have a question myself: which clamp can you use with it? Will it do DC current?

[Kbird]

What's the difference between the Peak function on the UT-61E and the Min/Max on the 139C?

Will the Min/Max on the 139C show me the peak of a sine wave: 230 * 1.414 = ~320V (assuming a crest factor of 1.414 for a perfect sine wave)?

No. It will display 0V or close.




EDIT: I have a question myself: which clamp can you use with it? Will it do DC current?

I ended up just getting the 210E and Modding it too since it was basically the same cost as an addon clamp but also gives me a 2nd Meter to Test with/compare , if needed.

KB

[Martini]

Well, the 139C has the min/max function

[Kbird]

I meant I got a 139C AND a 210E   = best of both worlds ...  not just a 210E , I got the 210E instead of an addon Clamp for the 139C as it was only a few $$ more at that time and it gave me a 2nd Meter for backup ....  the new 210E have a slightly better Chip now I believe.

[Martini]

Do you remember the clamp add-on reference?

[Kbird]

I don't sorry AFAIK Uni-T never made one but I believe it is limited to 60Amp on the 139C. I think the Cheapest I found was $38 which made the 210E a no brainer for me...

something like these perhaps.... I do not have or recommend either of them ,,,I just had a quick look on Amazon... 

perhaps wait for more replies

https://www.amazon.ca/dp/B00X3GDVWM/ref=sxbs_sxwds-stvpv2_1?pf_rd_m=A3DWYIK6Y9EEQB&pf_rd_p=3443526782&pd_rd_wg=Yfik6&pf_rd_r=BW2MG6BEH2YSDJBH6NNY&pf_rd_s=desktop-sx-bottom-slot&pf_rd_t=301&pd_rd_i=B00X3GDVWM&pd_rd_w=vVV3m&pf_rd_i=Clamp+Meter&pd_rd_r=0008d437-3747-4a38-bbb2-f1fe132dd42c&ie=UTF8&qid=1517782789&sr=1

https://www.amazon.ca/all-sun-Current-Working-Multimeter-Measurement/product-reviews/B013QH4K86/ref=dpx_acr_txt?showViewpoints=1

[Martini]

Clamp add-on seems like a shitty idea suddenly.

[carnage]

Has anyone tried using Energizer Ultimate Lithium in the UT139C?

Did it work properly?

[Kbird]

Have not tried them in the 139C

But I have/had them in a logitech mouse and they do strange things...one will drain to almost 0v  (0.404v) and the mouse becomes erratic as expected but if I leave the batteries out on the Workbench, a day or two later the battery is back to full Voltage.....has happened twice now but I am not using it in my Old Mouse any longer.... not sure if it is a drainage issue or what?

[carnage]

Have not tried them in the 139C

But I have/had them in a logitech mouse and they do strange things...one will drain to almost 0v  (0.404v) and the mouse becomes erratic as expected but if I leave the batteries out on the Workbench, a day or two later the battery is back to full Voltage.....has happened twice now but I am not using it in my Old Mouse any longer.... not sure if it is a drainage issue or what?

I read that there was some Brymen meter don't like Energizer Ultimate Lithium.

Thanks for the reply!

[Kbird]

Have not tried them in the 139C

But I have/had them in a logitech mouse and they do strange things...one will drain to almost 0v  (0.404v) and the mouse becomes erratic as expected but if I leave the batteries out on the Workbench, a day or two later the battery is back to full Voltage.....has happened twice now but I am not using it in my Old Mouse any longer.... not sure if it is a drainage issue or what?

I read that there was some Brymen meter don't like Energizer Ultimate Lithium.

Thanks for the reply!

Now I am curious ......what was happening with the Brymen?

The Lithium start out at high voltage .... like 1.78-1.81v .... the 2 I have used a while are in the 1.54-1.56 range though.


.

[carnage]

Have not tried them in the 139C

But I have/had them in a logitech mouse and they do strange things...one will drain to almost 0v  (0.404v) and the mouse becomes erratic as expected but if I leave the batteries out on the Workbench, a day or two later the battery is back to full Voltage.....has happened twice now but I am not using it in my Old Mouse any longer.... not sure if it is a drainage issue or what?

I read that there was some Brymen meter don't like Energizer Ultimate Lithium.

Thanks for the reply!

Now I am curious ......what was happening with the Brymen?

The Lithium start out at high voltage .... like 1.78-1.81v .... the 2 I have used a while are in the 1.54-1.56 range though.


.

Here's the link where I read about the Brymen       https://www.eevblog.com/forum/testgear/the-bm235-does-not-accept-lithium-batteries/