Mastech MS8239C review and teardown

[gameru]

           Greetings

This is my first review.And i'm a newbie in electronics.Sorry for my English,i know it is poor.
Let's get to work
Mastech MS8239c - 4000 counts,600V CAT III,update rate i think is  more then 3 times per sec,is not TRUE RMS
The DMM Mastech MS8239c does not have strengths,only the price 19 dollars.
Packaging
The carton box is nicely,inside we find the multimeter,test leads(decent,more flexible than UNI-T,total length 80cm),K-Type Thermocouple,manual,no battery (works with 2 x 1.5V AAA)

1.MS8239c it has a removable holster which is flexible.The meter stay nice and secure in holster (solid like a rock)
2.The screw to open up the battery compartment is metal threaded
3.The input jacks are split
4.Both fuse are rated 600V.The maker is ASTM.Dimensions : 6.3 x 32mm

Internal protection
The internal protection is weak.Only 2 PTC,some resistors and a diode bridge

Bad design
1.On the PCB we find the current shunt which is very close by conductor (COM)
2.The conductor of A jack touches the socket of 10A fuse
After this i put heat shrink tubing on all input jack
3.The selector switch contact have a type of grease on them ( i acted correctly by cleaning the contact?)

Display
 Is bright enough
The display passed  the known external pressure test
Back light is powerful and uniform
If you press the back light button, the light will stay permanently on (it has no timer)

Auto-Power-off
In manual says -after 30 minutes of no activity the meter will automatically shutdown.In real life sometimes after 5-10 minutes of no activity the meter will shutdown

Continuity mode
Fast response,no scratching

Capacitance
It has no internal residual capacitance
The  maximum reading is 100 microF

Diode
Voltage output in diode mode is 1.555V

Thermocouple and temperature
The multimeter contain an internal temperature sensor for measuring the ambient
K-Type Thermocouple it's a crap,the banana plug remains stuck in input jack.You need to apply a big force to get out
At the beginning it was a huge temp difference between MS8239c and Brymen BM869s,the MS8239c show with 8 degrees more then Brymen.After this i cleaned up the PCB and temperature difference was reduced

Accuracy
Was tested against my favorite meter BRYMEN BM869S
For this i will add pictures
As follows
Capacitance
Temperature
Resistance
DC V
AC V
Hz
DC mA
DC A
AC A

Click here for pictures

[joeqsmith]

Good write up.   I have a Mastech that I use for outside work.   

I like your Brymen.  Very nice meter! 

[gameru]

Good write up.   I have a Mastech that I use for outside work.   

I like your Brymen.  Very nice meter!

Thank you for encouragement
I'm very happy because you read my review.I am your fan,i saw all your video from youtube (it was a pleasure to watching)
I'm anxious to see your video about UT210e
I have a Voltcraft VC330 which is UNI-T UT210E inside
About Brymen, i'm fan

[joeqsmith]

I think you're my only fan.     Glad you have enjoyed the videos and always good to see another Brymen 869s out there.   Maybe we will see some videos from you in the future?   

I keep looking at the 210.   That 181 really took up a lot of time but now that it's over I will spend some time on it. 

What's the next meter you plan to look at?   

[gameru]

I think you're my only fan.     Glad you have enjoyed the videos and always good to see another Brymen 869s out there.   Maybe we will see some videos from you in the future?   

I keep looking at the 210.   That 181 really took up a lot of time but now that it's over I will spend some time on it. 

What's the next meter you plan to look at?

I do not think i will buy in the near future another multimeter.I'm newbie and for my knowledge it is too much what i have (Brymen BM869s,Voltcraft VC330,Mastech MS8239c)
Instead i want to learn how tu use an oscilloscope.Probable i will make the effort to buy an GWinstek (the cheapest model)

[kenjiru]

Initially I wanted to buy the Mastech MS8268, as it's quite popular and cheap, but I was put off by it's bulkiness.

Does MS8239C have any disadvantages compare to MS8268 for an electronics hobbyist doing mostly small Arduino projects?
Can somebody quickly compare the MS8239C with MS8268?

By the way, nice review!

[Magnets]

I'm looking for a cheap meter and saw these two (8268 and 8239c). the 8268 looks like a very old model originally going back to 2008 but has lots of reviews on amazon.

The 8268 has a self healing fuse, separate input jacks for current, it warns you if you use the incorrect inputs for your selection, the 10a fuse is accessible from the battery door. I think the accuracy is slightly better on the 8239c - 0.5%+3 vs 0.7%+2. But the 8268 looks incredibly bulky

To the OP: doesn't the 10a jack connect straight to the 10a fuse via the PCB? Does it make much difference if the jack is touching the fuse holder?

I notice your box is in English, all of the photos on aliexpress and gearbest show a chinese box, where did you order from?

edit: an older photo http://g02.a.alicdn.com/kf/UT8kLZxXhBaXXagOFbX3.jpg from a site that scrapes aliexpress reviews http://oki-dokki.com/otzyvy/multimetr-m044-ms8239c-auto-ac-dc_83348827.html

[gameru]

To the OP: doesn't the 10a jack connect straight to the 10a fuse via the PCB? Does it make much difference if the jack is touching the fuse holder?

I notice your box is in English, all of the photos on aliexpress and gearbest show a chinese box, where did you order from?

Until to put the heat shrink, the DMM show OL when measure more then 4A.After putting the heat shrink and cleaning the PCB with alcohol the DMM works right.
I ordered from Gearbest.I think they have a container in Europe.Because the parcel was sent to me from Belgium.The shipping time was 1week
I forgot to mention in review,suffer of overshoot
I recommend you to buy a real DMM

[avocado]

I am considering to buy this DMM after reading this thread and not being able to find what I want in my budget range.

[Hydrawerk]

Do not buy a DMM with one jack for voltage and mA.

[Hydrawerk]

 

[avocado]

Thanks for the reminder.

I did not take a look at the details of the front face of the DMM.
But I did notice it has 3 socket and I thought the all A measurement was in a different socket.
thanks again. I will pay more attention from here then on.

[Kilrah]

Wow, first time I see one like that (apart from the $10 thingies with 2 jacks only of course).

[mariustaciuc]

Yet another review and comparison between Fluke 87 and Mastech MS8268:

https://www.youtube.com/watch?v=_eXDEUyI8L0=youtu.be