Author Topic: Sparkfun multimeter video teardown....  (Read 17679 times)

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Offline Fungus

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Sparkfun multimeter video teardown....
« on: February 09, 2015, 09:39:04 pm »
I just did a teardown video of a $15 Sparkfun multimeter. I think it's pretty well designed/built for the money.



Don't be too hard on me, it's my first video. I mainly did it just to practice using the camera, etc.

I also caught a cold half way through filming so the voice varies a bit  :-(

« Last Edit: February 09, 2015, 09:49:48 pm by Fungus »
 

Offline ModemHead

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Re: Sparkfun multimeter video teardown....
« Reply #1 on: February 10, 2015, 03:16:15 am »
Thanks for the video.  I like your presentation style and the camera setup, although the auto-focus capability of your camera is a bit sluggish.



Awwww, did you have to carp on the Fluke being big and slow and heavy?  Too bad you didn't crack the case just for a quick comparison of industrial-grade versus hobby-grade.  Just for educational reasons, of course.  :)

You probably already know this, but the Sparkfun meter is essentially the same ICL7106-based design as the ugly cheap-Os.  There is nothing inherently wrong with a 7106-based meter, it can be a very good measuring instrument as you demonstrated.  The Sparkfun version shows it only takes a few bucks to make it a bit more useable and reliable tool.
 

Offline Excavatoree

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Re: Sparkfun multimeter video teardown....
« Reply #2 on: February 10, 2015, 04:13:30 am »
Awwww, did you have to carp on the Fluke being big and slow and heavy?  Too bad you didn't crack the case just for a quick comparison of industrial-grade versus hobby-grade.  Just for educational reasons, of course.  :)

The 27 is older technology, and yes, it is a bit slow.  A comparison to a 117 or even a model 77 (I, II, III, or IV) would have been more appropriate.   The benefit of the 27 is that it is rugged - try dropping it and the sparkfun meter.   (That's why it's heavier.  Measure the thickness of the plastic body)  I've purchased 27's for the same 15 dollars that one would have to give for the sparkfun.

In short, the comparison seems a bit unfair to me as well. 
« Last Edit: February 10, 2015, 04:15:06 am by Excavatoree »
 

Offline Excavatoree

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Re: Sparkfun multimeter video teardown....
« Reply #3 on: February 10, 2015, 04:14:20 am »
I forgot to add that it's a good thing that Sparkfun meter doesn't have a yellow holster, I almost confused it with a Fluke.
 

Offline Fungus

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Re: Sparkfun multimeter video teardown....
« Reply #4 on: February 10, 2015, 04:17:48 am »
Thanks for the video.  I like your presentation style and the camera setup, although the auto-focus capability of your camera is a bit sluggish.

Thanks!

I'll see if I can tweak the auto-focus. It has different speed settings but I don't remember what it was set to. I think I need a bit more light in the talking-head shots as well.

(These are all things you notice in the editing stage...)

Awwww, did you have to carp on the Fluke being big and slow and heavy?

I was trying to figure out a way to explain why I like using the Sparkfun meter.

It's not easy to put into words but I suspect it's the same reason why Dave normally uses his little Brymen 357 when he's got shelves full of high-end Flukes, $1000 Gossen MetraWatts, etc., just a few feet away.

Too bad you didn't crack the case just for a quick comparison of industrial-grade versus hobby-grade.  Just for educational reasons, of course.  :)

Dave's already done it and I don't think I could do better (and besides, my video was already getting too long...)



They really are a work of art inside.

You probably already know this, but the Sparkfun meter is essentially the same ICL7106-based design as the ugly cheap-Os.  There is nothing inherently wrong with a 7106-based meter, it can be a very good measuring instrument as you demonstrated.  The Sparkfun version shows it only takes a few bucks to make it a bit more useable and reliable tool.

If you search for "VC830L" on eBay you get a lot of multimeters that look like the Sparkfun meter,

http://www.ebay.com/sch/i.html?_nkw=VC830L

Some are a lot cheaper, some have backlights, some have hold buttons... etc.

Anyway: One of the scenes that ended up on the cutting room floor was a scene pointing out that the two cheapo meters have the exact same model number on the outside ("DT-830B") but are completely different meters on the inside.

Sure, you can get a generic "VC830L" on eBay, but will it be the same as the Sparkfun meter? I dunno ... but I think it's better to pay a couple of extra bucks for postage and get one from Sparkfun.

 

Offline Fungus

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Re: Sparkfun multimeter video teardown....
« Reply #5 on: February 10, 2015, 04:25:57 am »
Awwww, did you have to carp on the Fluke being big and slow and heavy?  Too bad you didn't crack the case just for a quick comparison of industrial-grade versus hobby-grade.  Just for educational reasons, of course.  :)

The 27 is older technology, and yes, it is a bit slow.  A comparison to a 117 or even a model 77 (I, II, III, or IV) would have been more appropriate. 

That's the only Fluke I own...

According to the Fluke web page the 117 is a bit lighter but not really much smaller (about 3cm shorter, width and height basically the same as a 27...)

I think Dave's mentioned that modern Flukes can be annoying as well - "AC" mode by default, anybody...? 
 

Offline Fungus

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Re: Sparkfun multimeter video teardown....
« Reply #6 on: February 10, 2015, 04:27:48 am »
I forgot to add that it's a good thing that Sparkfun meter doesn't have a yellow holster, I almost confused it with a Fluke.

Maybe Sparkfun should make one and sell it as an accessory...   >:D

 

Offline Fungus

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Re: Sparkfun multimeter video teardown....
« Reply #7 on: February 10, 2015, 04:51:58 am »
the auto-focus capability of your camera is a bit sluggish.

I'll see if I can tweak the auto-focus. It has different speed settings but I don't remember what it was set to.

I've checked and it was already set to 'fastest'.

Not much I can do - maybe be a bit more careful when moving things towards the camera.


 

Offline Lightages

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Re: Sparkfun multimeter video teardown....
« Reply #8 on: February 10, 2015, 05:54:28 am »
Thanks for the review. I bet there are still people who will defend those bargain garbage bin meters.
 

Offline ModemHead

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Re: Sparkfun multimeter video teardown....
« Reply #9 on: February 10, 2015, 06:21:31 am »
Anyway: One of the scenes that ended up on the cutting room floor was a scene pointing out that the two cheapo meters have the exact same model number on the outside ("DT-830B") but are completely different meters on the inside.
I'm not positive about this, but I think those "830" DMMs originated in Taiwan back in the 80s when they could command a higher profit margin.  Once the Chinese began to copy them, they started taking out bits and pieces and coming up with ways to make them cheaper.  My go-to line here is I think the basic 830 schematic is printed on the back of every restaurant menu in ShenZhen.



Anyway, looking forward to your next video.  :-+
 

Offline JohnnyBerg

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Re: Sparkfun multimeter video teardown....
« Reply #10 on: February 10, 2015, 06:27:01 am »
Nice review, I enjoyed it very much!

I liked your presentation style, and unbiased look at the meters!
« Last Edit: February 10, 2015, 10:08:43 am by JohnnyBerg »
 

Offline retiredcaps

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Re: Sparkfun multimeter video teardown....
« Reply #11 on: February 10, 2015, 07:17:07 am »
I think Dave's mentioned that modern Flukes can be annoying as well - "AC" mode by default, anybody...?
The 87V defaults to AC in the current range.  Before that, the original 87 and 87 III defaults to DC in the current range.  Thus, on the 87V, you have to hit the yellow button each time you want to measure DC current.

Some of the Brymen meters remember which mode you are in (AC or DC) even after you turn it off.

PS. I suspect the reasons Dave uses the Brymen 257 in his videos recently is due to the smaller size and the larger lcd digits compared to the 87V.

With a smaller meter, he can fit more other "stuff" in frame composition.  With the larger lcd digits, the audience and Dave can see the readings more easily.
 

Offline rollatorwieltje

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Re: Sparkfun multimeter video teardown....
« Reply #12 on: February 10, 2015, 09:21:29 am »
I had similar experiences with those cheap nasty ones. Surprisingly accurate for something that looks that horrible. Mine (Topcraft TMMH 930) even came with a rubber boot. The interior was completely different though, it used all through hole stuff. The connectors were also full tubes, no folded mess. The mA range was fused, the 10A range wasn't.

If you want to laugh (or cry) even more, cut the probe leads and see how much copper is there. Mine had only a few strands that even made poor contact at the connector. I noticed it when the leads actually started glowing very brightly near the connector when measuring the current of a discharging capacitor bank (wasn't really supposed to draw that much current, but a certain FET lived up to it's name, Fiercely Exploding Transistor, effectively shorting it).

A technical remark, check your audio levels. I had to put my tablet at max volume. Looking at the audio track in Audacity most of the speech never exceeds about 1/3th, several other random Youtube videos seem normalized at around 0.5.
 

Offline retiredcaps

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Re: Sparkfun multimeter video teardown....
« Reply #13 on: February 10, 2015, 09:51:26 am »
A technical remark, check your audio levels. I had to put my tablet at max volume.
Same here on a computer running lubuntu using vlc to view video.  I had vlc at 125% and was still straining to hear a bit.
 

Offline cosmicray

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Re: Sparkfun multimeter video teardown....
« Reply #14 on: February 10, 2015, 10:05:47 am »
I forgot to add that it's a good thing that Sparkfun meter doesn't have a yellow holster, I almost confused it with a Fluke.

Maybe Sparkfun should make one and sell it as an accessory...   >:D
Didn't Sparkfun go a round with Fluke about use of a particular shade of yellow on test gear ?
it's only funny until someone gets hurt, then it's hilarious - R. Rabbit
 

Offline tom66

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Re: Sparkfun multimeter video teardown....
« Reply #15 on: February 10, 2015, 10:28:26 am »
Could those glass fuses really meet a CATIII rating? I'd imagine they would destroy themselves on a serious overload. I've had glass fuses explode on me when used in mains power supplies that fail, and that's just on a normal 32A breaker UK ring mains... not particularly high energy compared to what else is out there.

BS1363 fuses are cheap (£0.12 in bulk, Bussman genuine), I wonder if any MM manufacturers have considered using them. They're ceramic and rated to 250V and will safely interrupt normal mains failure current without a dangerous explosion. Obviously, it would limit the current range to 250V, but I can't think it'd be a good idea to use a meter like this above 250V, especially a mains connected one.
 

Offline miguelvp

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Re: Sparkfun multimeter video teardown....
« Reply #16 on: February 10, 2015, 07:24:49 pm »
I forgot to add that it's a good thing that Sparkfun meter doesn't have a yellow holster, I almost confused it with a Fluke.

Maybe Sparkfun should make one and sell it as an accessory...   >:D
Didn't Sparkfun go a round with Fluke about use of a particular shade of yellow on test gear ?

Yup, those are the meters that Fluke put a hold on importing and they were either destroyed or returned to origin. But they did offer to match the cost as a charitable contribution or something like that. I think this was 6 months or so ago.
 

Offline Fungus

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Re: Sparkfun multimeter video teardown....
« Reply #17 on: February 10, 2015, 08:58:46 pm »
A technical remark, check your audio levels. I had to put my tablet at max volume.
Same here on a computer running lubuntu using vlc to view video.  I had vlc at 125% and was still straining to hear a bit.

 :(

Premiere Pro strikes again. The very last thing I did before exporting the video was "Select All->Normalize".

I'll have to play around and figure out what Adobe understands by "normalize". Premiere Pro is just a huge trap for new players.

 

Offline Fungus

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Re: Sparkfun multimeter video teardown....
« Reply #18 on: February 10, 2015, 09:00:16 pm »
I forgot to add that it's a good thing that Sparkfun meter doesn't have a yellow holster, I almost confused it with a Fluke.
Maybe Sparkfun should make one and sell it as an accessory...   >:D
Didn't Sparkfun go a round with Fluke about use of a particular shade of yellow on test gear ?
Yup, those are the meters that Fluke put a hold on importing and they were either destroyed or returned to origin.

...as mentioned in the video.
 

Offline rollatorwieltje

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Re: Sparkfun multimeter video teardown....
« Reply #19 on: February 10, 2015, 09:13:56 pm »

 :(

Premiere Pro strikes again. The very last thing I did before exporting the video was "Select All->Normalize".

I'll have to play around and figure out what Adobe understands by "normalize". Premiere Pro is just a huge trap for new players.

It looks like it did "peak normalize". There are some loud spikes (clicking of range switch, hitting the desk etc), it used that as maximum. You probably want to increase the overall gain and just let those peaks clip.
 

Offline Fungus

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Re: Sparkfun multimeter video teardown....
« Reply #20 on: February 10, 2015, 09:25:12 pm »
Could those glass fuses really meet a CATIII rating?

It's borderline at best, that's why I said "maybe".

With CAT III you still have arc protection between you and "utility power" (CAT IV). In theory the fuse can't arc over.

http://en.wikipedia.org/wiki/Arc-fault_circuit_interrupter

http://faculty.riohondo.edu/jfrala/fluke_multimeters_-_abcs_of_multimeter_safety_multimeter_safety_and_you_application_note.pdf

So yes, it might be CAT III but glass fuses aren't a good thing.

(Experts: Please correct me if I'm wrong about any of this)


HRC fuses aren't expensive or hard to get (it's basically the same construction as the glass fuse but filled with sand). I don't know why all multimeters don't have them.

 

Offline Fungus

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Re: Sparkfun multimeter video teardown....
« Reply #21 on: February 10, 2015, 09:59:47 pm »

 :(

Premiere Pro strikes again. The very last thing I did before exporting the video was "Select All->Normalize".

I'll have to play around and figure out what Adobe understands by "normalize". Premiere Pro is just a huge trap for new players.

It looks like it did "peak normalize". There are some loud spikes (clicking of range switch, hitting the desk etc), it used that as maximum. You probably want to increase the overall gain and just let those peaks clip.

Looks like it...

All that would do is find the loudest sound in the video and normalize everything to that - not at all what I wanted.

I've just googled a bit and seen several pages saying there's no way to do what I need automatically (ie. some sort of automatic gain control).

The best thing I could find so far is to go through the video manually looking for loud sounds, chop the video either side of the sound, then do "Normalize all peaks" (which normalizes each individual clip to the level of the loudest sound in it).  :-//

(Maybe I'm just using the wrong editing software...)

 

Offline Wytnucls

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Re: Sparkfun multimeter video teardown....
« Reply #22 on: February 10, 2015, 10:19:59 pm »
Could those glass fuses really meet a CATIII rating?

It's borderline at best, that's why I said "maybe".

With CAT III you still have arc protection between you and "utility power" (CAT IV). In theory the fuse can't arc over.

http://en.wikipedia.org/wiki/Arc-fault_circuit_interrupter

http://faculty.riohondo.edu/jfrala/fluke_multimeters_-_abcs_of_multimeter_safety_multimeter_safety_and_you_application_note.pdf

So yes, it might be CAT III but glass fuses aren't a good thing.

(Experts: Please correct me if I'm wrong about any of this)


HRC fuses aren't expensive or hard to get (it's basically the same construction as the glass fuse but filled with sand). I don't know why all multimeters don't have them.

HRC fuses are an IEC requirement now, with a voltage rating equal to the meter's highest CAT voltage. Glass fuses don't meet those standards.
« Last Edit: February 10, 2015, 10:25:07 pm by Wytnucls »
 

Offline Fungus

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Re: Sparkfun multimeter video teardown....
« Reply #23 on: February 11, 2015, 03:36:31 am »

 :(

Premiere Pro strikes again. The very last thing I did before exporting the video was "Select All->Normalize".

I'll have to play around and figure out what Adobe understands by "normalize". Premiere Pro is just a huge trap for new players.

It looks like it did "peak normalize". There are some loud spikes (clicking of range switch, hitting the desk etc), it used that as maximum.

Looks like it...

(Maybe I'm just using the wrong editing software...)

I've been looking around for a few hours and it doesn't look like there's a way to do it in Premiere Pro.

Cyberlink PowerDirector can do it with a single click. It also seems to do this type of editing much more easily then Premiere Pro. I'll give it more of a test tomorrow.

 

Offline mrgregs

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Re: Sparkfun multimeter video teardown....
« Reply #24 on: February 11, 2015, 09:34:27 pm »

 :(

Premiere Pro strikes again. The very last thing I did before exporting the video was "Select All->Normalize".

I'll have to play around and figure out what Adobe understands by "normalize". Premiere Pro is just a huge trap for new players.

It looks like it did "peak normalize". There are some loud spikes (clicking of range switch, hitting the desk etc), it used that as maximum.

Looks like it...

(Maybe I'm just using the wrong editing software...)

I've been looking around for a few hours and it doesn't look like there's a way to do it in Premiere Pro.

Cyberlink PowerDirector can do it with a single click. It also seems to do this type of editing much more easily then Premiere Pro. I'll give it more of a test tomorrow.

Could you try something like exporting the audio, running it through something like the Levelator, and then reimporting it? That was the way I used to normalize the audio in Sony Vegas.
 


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