Re-brand of Mastech MS8229 from Harbor Freight (item #98674) - Page 1
Forum section: electronics / testgear

author: ttt
author_rank: Regular Contributor
timestamp: November 26, 2013, 03:46:42 am
content: Hi, I never posted here before (just lurking) but maybe someone is interested in some photos of a re-brand of a Mastech 8228(?) multimeter I just acquired. The particular re-brand I picked up was from Harbor Freight (ugh, I know), item # 98674 under the brand "Cen-Tech". With a 25% rebate I got this one for about $45 to the door ((44.99 * 0.75) * 1.085 (tax) + 6.99 (shipping)).I haven't seen any particular reviews of this model, but what makes it somewhat unique are the Lux (luminosity) and dB (sound level) measuring capabilities. For me the important parts are the uA/mA ranges which I miss on my own handheld Flukes. While testing this meter it had no problem staying within spec. Not great specs but good enough for my purposes. From the manual:DCRange Res. Acc.400uA 0.1uA4000uA 1uA40mA 10uA +- 1.2%400mA 100uA4A 1mA-----------------------10A 10mA +- 2.0%The other specs are similar, all +-1.2% and +-2% in the higher ranges. +-3% for capacitance. As you can see in the pictures there are tons of pots. I suppose I could spend some time calibrating this against my Fluke 8840A if have the patienceEdit: Changed title to mention 8229 instead of 8228 which this indeed is.

author: retiredcaps
author_rank: Super Contributor
timestamp: November 26, 2013, 04:54:24 am
content: Quote from: ttt on November 26, 2013, 03:46:42 amThanks for the teardown photos. I believe it is a Mastech 8229.http://www.p-mastech.com/images/SPEC/ms8229.pdf

author: AndersAnd
author_rank: Frequent Contributor
timestamp: November 26, 2013, 06:22:25 am
content: Quote from: retiredcaps on November 26, 2013, 04:54:24 amYes and it even says MS8229-1 right on the PCBs silkscreen. And thanks for the teardown.Here's some other teardown pictures I found of a Mastech 8229:http://ctc-labs.soup.io

author: Wytnucls
author_rank: Super Contributor
timestamp: November 26, 2013, 07:37:26 am
content: The design of this meter is a bit strange and gimmicky. Lux and dB? Cheap trimpots and electrolytic caps galore. Strange loose wiring all over the place. At least they seem to have used decent connectors.I like the 3 AAA batteries. That should be good for endurance, although, with the lit connection jacks, that might not help much.No fuse on the mA range; just a polyswitch (Careful with high voltages). The main A range fuse looks a bit skinny, but it is easily accessed.Minimal protection overall, with one PTC and no MOVs in sight on the pictures.

author: saturation
author_rank: Super Contributor
timestamp: November 26, 2013, 01:32:11 pm
content: .. yes and no safety approvals I can see stamped from any 3rd party testing agency, UL, TUV, NRTL etc.,Quote from: Wytnucls on November 26, 2013, 07:37:26 am

author: Lightages
author_rank: Unknown
timestamp: November 26, 2013, 04:57:53 pm
content: Every time I see a Mastech it confirms my feelings about their construction. This one is really built strangely.

author: marshallh
author_rank: Unknown
timestamp: November 26, 2013, 06:42:39 pm
content: I had one of those from HF. Just like yours, but the earlier revision (bought in '08)They used a PIC12 just for the blinking led banana jacks. It works fine, but is a little try-hard.

author: Dongulus
author_rank: Regular Contributor
timestamp: November 26, 2013, 07:20:11 pm
content: Does someone know the reasoning for the hash pattern on the wide traces?

author: AndersAnd
author_rank: Frequent Contributor
timestamp: November 26, 2013, 10:16:36 pm
content: Quote from: Dongulus on November 26, 2013, 07:20:11 pmhttps://en.wikipedia.org/wiki/Copper_pour

author: Dongulus
author_rank: Regular Contributor
timestamp: November 26, 2013, 11:52:31 pm
content: Quote from: AndersAnd on November 26, 2013, 10:16:36 pmAh,hatchnot hash. No wonder a Google search returned no results.

author: deth502
author_rank: Frequent Contributor
timestamp: November 27, 2013, 12:42:55 am
content: Quote from: Wytnucls on November 26, 2013, 07:37:26 ammost of this ^^the cheap trim pots everywhere do not instill confidence in me for this meter, nor do the wires running everywhere. the lit jack connectors seem gimmicky, although i can see the appeal for a niche market of beginners.i do like the idea of the db meter, i could use that.next time im at my local hf, i might pick one of those up for shits and giggles. whats another meter in the pile, anyway?

author: deth502
author_rank: Frequent Contributor
timestamp: December 21, 2013, 10:59:29 pm
content: Quote from: deth502 on November 27, 2013, 12:42:55 amso i picked one of these up yesterday. some odd things i noticed before even opening the box. first, for some reason, it states that it will only work in altitudes up to 7k ft. secondly, i see the box says that it will measure dc current up to 200A. wonder if i did so and brought back a chunk of melted plastic if they'd cover it under warranty?