Multimeter suggestion for 12 yo  Light up LEDs -  Easy fuse change - Page 1
Forum section: electronics / testgear

author: ez24
author_rank: Super Contributor
timestamp: July 16, 2018, 05:02:30 am
content: Hi(changed the original post to update)Looking for a meter for a 12 yo. As suggested - get one that can light up an LED. Fuse has to be changed by a 12yo. Anengs are out because their fuses are too hard to replace. But maybe two 8008s if the suggested meter is too expensive (assuming they can light an LED ?).thanks

author: ataradov
author_rank: Super Contributor
timestamp: July 16, 2018, 05:33:15 am
content: Uni-T UT136. Easy to replace batteries and fuses can be replaced by cheap ones if blown. And if you blow the fuses it will be functionally equivalent to that Fluke, except you can get two Uni-Ts for that price.

author: ez24
author_rank: Super Contributor
timestamp: July 16, 2018, 05:48:35 am
content: Quote from: ataradov on July 16, 2018, 05:33:15 amThe UNI-T UT136B uses 9v batterieshttps://smile.amazon.com/UNI-T-UT136B-Multimeter-Frequency-Resistance/dp/B06XSVMV25/ref=sr_1_1?s=hi&ie=UTF8&qid=1531719994&sr=1-1&keywords=uni-t+ut136b

author: ataradov
author_rank: Super Contributor
timestamp: July 16, 2018, 05:52:45 am
content: Quote from: ez24 on July 16, 2018, 05:48:35 amIndeed. I was only focusing on easy to replace. I'm not sure that 9V batteries are all that expensive in this application, they last quite some time. I had a couple of those meters for a few years (one gets a lot of use for work), and I never had to replace the batteries yet.

author: Gregg
author_rank: Super Contributor
timestamp: July 16, 2018, 05:56:21 am
content: Banggood has the Aneng AN8009 for $21.99 shipped from the US warehouse. It uses AAA cells if that is a problemhttps://www.banggood.com/ANENG-AN8009-True-RMS-NCV-Digital-Multimeter-9999-Counts-Backlight-AC-DC-Current-Voltage-Tester-p-1216900.html?rmmds=search&cur_warehouse=USA

author: ataradov
author_rank: Super Contributor
timestamp: July 16, 2018, 05:57:30 am
content: ANENG has horrible view angles. How do you people live with that? I could not use it pas first two minutes.

author: ez24
author_rank: Super Contributor
timestamp: July 16, 2018, 06:15:15 am
content: Quote from: Gregg on July 16, 2018, 05:56:21 amFrom a search, the fuse in the 8009 is just as hard to replace as the 8008

author: ataradov
author_rank: Super Contributor
timestamp: July 16, 2018, 06:17:48 am
content: Quote from: ez24 on July 16, 2018, 06:15:15 amIt requires unscrewing 4 screws, this will probably be the minimum you will find in any cheap meter where fuses are not exposed in their own compartments.But it uses some weird tiny fuses, which are probably harder to find.

author: ez24
author_rank: Super Contributor
timestamp: July 16, 2018, 06:24:28 am
content: Quote from: ataradov on July 16, 2018, 05:52:45 amEvery meter that I have that uses 9v batteries ALWAYS has a dead battery. This because my meters do not have auto power off and I screw up every time.So this meter goes to the top of my list because it has auto power off. FYI The Fluke 101 at $50 is too much. The kid may not even touchthanks

author: ataradov
author_rank: Super Contributor
timestamp: July 16, 2018, 06:29:03 am
content: Quote from: ez24 on July 16, 2018, 06:24:28 amYeah, I wish it would not auto-power offI know you can disable it if you hold one of the buttons while powering on, but that's just annoying.

author: mtdoc
author_rank: Super Contributor
timestamp: July 16, 2018, 06:38:38 am
content: Thw Uni-T 136b is a good recommendation but it does have one big flaw - especially for a 12 year old learning electronics - it won’t light up an LED.I learned this when using mine while teaching kids in my son’s school maker space.

author: ez24
author_rank: Super Contributor
timestamp: July 16, 2018, 06:41:51 am
content: Quote from: mtdoc on July 16, 2018, 06:38:38 amLighting an LED is now at the top (and edit the original post)

author: Mr. Scram
author_rank: Super Contributor
timestamp: July 16, 2018, 06:48:24 am
content: Quote from: ataradov on July 16, 2018, 05:57:30 amThe Aneng meters leave a few things to desire, but the viewing angles of the meters I've seen are on par with those of high end Fluke and Keysight meters. I'm not sure what you're talking about, unless you're talking about that new model Dave recently reviewed.

author: ataradov
author_rank: Super Contributor
timestamp: July 16, 2018, 06:51:57 am
content: Quote from: Mr. Scram on July 16, 2018, 06:48:24 amNo, I'm talking about plain old AN8008. It starts to wash off even if you look at it dead on, and completely invisible if you look from the top. I've read similar complaints in the ANENG thread. It is nothing like Uni-T of Fluke that I have, not even close.

author: Mr. Scram
author_rank: Super Contributor
timestamp: July 16, 2018, 07:08:08 am
content: Quote from: ataradov on July 16, 2018, 06:51:57 amTry turning the backlight on. The Fluke displays I've seen wash out dramatically when viewed at anything beyond 90 degrees with the backlight on. Regardless, I've not found the AN8008 screen to be problematic when used normally. The meter does leave a fair few things to be desired, but the screen contrast doesn't seem to be an issue. Even when I compare it to high end meters.I'm not sure I'd like to give a child a meter that isn't as safe as a meter should be, though. I understand an expensive meter isn't really in the books, but novices need safe and good quality meters even more than more experienced folks do. It'd probably be good to assume that he's going to poke it in the mains sooner or later, and that it may very well be on a current range when he does.

author: mtdoc
author_rank: Super Contributor
timestamp: July 16, 2018, 07:12:50 am
content: I ended up buying 5 of the Aneng 8008s for my kids school maker space. So far they’ve worked out well. I haven’t noticed the screen viewing angle to be an issue.What’s the difficulty with replacing the fuses? Finding the replacements? Removing the 4 small screws to access the fuses should be a piece of cake for a 12 year old.

author: mtdoc
author_rank: Super Contributor
timestamp: July 16, 2018, 07:22:03 am
content: Quote from: Mr. Scram on July 16, 2018, 07:08:08 amI understand that concern. What I did with the meters I bought for my kids school was write in large letters with a permanent marker on the side of the meter: “ To be used with battery powered circuits only!”Of course in a school setting there will be some supervision...Still, I think a 12 year old, if given a stern warning with an explanation of the danger, would be ok.

author: Mr. Scram
author_rank: Super Contributor
timestamp: July 16, 2018, 07:32:00 am
content: Quote from: mtdoc on July 16, 2018, 07:22:03 amI have to admit I'm mainly thinking of myself at twelve years old. The fact that I'm still around to type this is a minor miracle, despite plenty of solid advice. Let's say I was an empirically inclined child.There's some tension betwee trying to instil curiosity and dampening it enough, so that nobody gets hurt permanently.

author: HKJ
author_rank: Super Contributor
timestamp: July 16, 2018, 07:32:37 am
content: There might be some good ideas for meters in my list:https://lygte-info.dk/info/DMMReviews.htmlWhat about a ZT301:https://lygte-info.dk/review/DMMBSide%20ZT301%20UK.html

author: Fungus
author_rank: Super Contributor
timestamp: July 16, 2018, 10:19:12 am
content: Quote from: ataradov on July 16, 2018, 06:51:57 amMaybe nobody notices that because they don't look at the meter from above.LCDs have limited viewing angles. If the meter is usually flat on a table in front of you then it makes sense to optimize for that, not some artificial viewing angle ("above"?)

author: Fungus
author_rank: Super Contributor
timestamp: July 16, 2018, 10:31:13 am
content: I'd get the ANENG 860B+. I own a few meters but the 860B+ is easily the best at lighting up LEDs. It's also rubberized and will take alotmore abuse then one of the flimsy little AN800X models ever will.It also has proper milliamp rangesandall the current ranges are on separate input jacks (ie. you need to move the leads from "normal" position to blow a fuse).Plus it has more buttons and is a much better meter all-round IMHO (nb. I own both types).Don't worry about 'easy' fuse change. The more difficult it is, the faster they'll learn not to blow fuses.Bonus: An 860B+ will hold together perfectly even after they've lost and/or stripped the threads off the fuse-access screws - you can't say that for the AN800X models.

author: joeqsmith
author_rank: Super Contributor
timestamp: July 16, 2018, 11:21:23 am
content: Some of the cheap meters I looked at have used a PTC rather than a fuse for the low current measurements.Cliff started a thread a while back and his post shows a $10 meter. I bought this same meter but it still in the wrapper.https://www.eevblog.com/forum/beginners/6000-count-dmms-(is-$9-a-new-newbie-low)/You could buy them a resistor and a battery. Instant LED light up tester...

author: HKJ
author_rank: Super Contributor
timestamp: July 16, 2018, 11:29:09 am
content: Quote from: joeqsmith on July 16, 2018, 11:21:23 amPTC usual means higher burden voltage in the high mA range.

author: joeqsmith
author_rank: Super Contributor
timestamp: July 16, 2018, 11:47:19 am
content: Quote from: HKJ on July 16, 2018, 11:29:09 amI modified a really inexpensive analog meter and used a PTC rather than a fuse for the current input. I thought the PTC was under 5 ohms. Fuse will also have some resistance. The UNI-T UT61E had one of the worst burden voltages I measured because of the choices made in other parts of the design. The choice of shunts can drop far more than a PTC. I'm not sure but would a 12YO who is just starting out, care about burden voltage?There may be some benefit to a child who is just learning with low voltages and making mistakes, not to have to change the fuse.

author: HKJ
author_rank: Super Contributor
timestamp: July 16, 2018, 11:56:12 am
content: Quote from: joeqsmith on July 16, 2018, 11:47:19 amA 1ohm shunt and the fuse is also about 1ohm, i.e. about 2ohm to 2.5ohm on the high mA range is very common.The UNI-T with shunts in series and diodes to lead voltage around one of them is not good for burden voltage.The PTC is an advantage if you make many mistakes, but a meter with 5x20mm fuses is very cheap to replace fuses in and safe enough when staying at low voltage and after a fused outlet.

author: Fungus
author_rank: Super Contributor
timestamp: July 16, 2018, 12:51:48 pm
content: Quote from: joeqsmith on July 16, 2018, 11:21:23 amOr just a CR2032 battery - CR2032s have a built-in current limiting resistor.

author: ataradov
author_rank: Super Contributor
timestamp: July 16, 2018, 04:30:44 pm
content: Quote from: Fungus on July 16, 2018, 10:19:12 amAnd I may not notice it either, except I looked a lot at UT136 and from the first moment I powered on AN8008 I felt discomfort. I had to adjust my position to see the reading. So AN8008 was discarded (I actually want to do OLED conversion by tapping into LCD lines, but that's a long term project).

author: mtdoc
author_rank: Super Contributor
timestamp: July 16, 2018, 04:59:47 pm
content: I think the idea of having a DMM is to have as many tools you need in one package. Having to find a battery to test an LED is not ideal.Also, a battery alone won’t help when you need to test an in circuit LED or a surface mount LED. Yes, SMD LEDs are increasingly being used by kids new to electronics when they makepaper circuits.

author: ataradov
author_rank: Super Contributor
timestamp: July 16, 2018, 05:02:39 pm
content: Quote from: mtdoc on July 16, 2018, 04:59:47 pmIf you want to test the LEDs, then UT136 works just fine, they just won't light up in the process. If you want to light them up (what kind of a requirement is that for a test tool?), then use batteries or whatever.Or not.

author: mtdoc
author_rank: Super Contributor
timestamp: July 16, 2018, 05:06:29 pm
content: Quote from: ataradov on July 16, 2018, 05:02:39 pmYou clearly haven’t worked with kids new to electronics.

author: ataradov
author_rank: Super Contributor
timestamp: July 16, 2018, 05:08:47 pm
content: Quote from: mtdoc on July 16, 2018, 05:06:29 pmI was a kid working with electronics.The thought of lighting up leds with a tester never crossed my mind. It would have been also nice to have a DMM instead of analog meter, but you get used to tools you have. If that somehow discourages you, then you may be better off doing something else.12 yo is not that young.

author: mtdoc
author_rank: Super Contributor
timestamp: July 16, 2018, 05:34:38 pm
content: Kids these days...when I was a kid ....., we would have loved to have an analog meter. All we had was a galvanometer and a voltaic pile as a voltage source, but we were happy.But I know what you mean . Still IMO given the multitude of cheap DMMs these days, it’s silly to give a kid a meter that does not light up LEDs. There’s joy to be had for a newbie when they see an LED light up and nothing worse than building your first circuit with an LED and having it not light up and not easily being able to troubleshoot it with your DMM. Also, I found that using the DMM to light up LEDs is an excellent way to teach them about diode polarity.

author: CustomEngineerer
author_rank: Frequent Contributor
timestamp: July 17, 2018, 12:00:07 am
content: Children are our future, so important to keep them safe. Thats why I recommend 2x Fluke 88V.

author: sleemanj
author_rank: Super Contributor
timestamp: July 17, 2018, 01:08:35 am
content: If it wasn't for the LED requirement, I would have recommended the MS8233D or MS8233E and various rebadges thereof (ADM01 / ADM02), yes it is "only" a 2000 count meter, but it has 5x20 fuses on both ranges, is physically solid and with rubber boot, APO, backlight, auto ranging, max capture, it's not quite so blatantly "over rated" in terms of it's warning marks etc (specifically, it's CAT II 600V on the volt ranges, and marked as 250V max on the current ranges)OEM is Mastech in green, custom branded by a few, mainly bside who does it in blue (ADM01/ADM02), and Peakmeter who does it in orange.Difference between the two models is D/01 has frequency count mode, while E/02 has temperature mode, I think temperature is more useful myself generally.Price on Aliexpress typically around the $12-14 mark, sometimes you can get them under $10.Achilles heel for your requirements though, can't light an LED in diode test mode.

author: rstofer
author_rank: Super Contributor
timestamp: July 17, 2018, 01:15:44 am
content: For a fact, the Aneng 8008 will light up a blue LED in diode test mode.Don't replace the fuses, replace the meter!Seriously, have the 12 YO do voltage measurements andavoid current measurementsuntil the underlying theory is well understood. I just don't see current measurements as being all that important because, more often than not, the current is flowing through a resistor. It is just as easy to measure voltage drop and use a calculator.Perhaps current measurements with supervision. It isn't the measurement that's the problem, it's overlooking putting the leads back where they belong that causes the problems. On the Aneng 8008, it doesn't take a lead change to measure uA. Hm...When I was a kid, I was told not to touch the 120V stuff on my dad's workbench. Of course I touched it. Got bit a couple of times until I learned more about the theory. These days I power my stuff from batteries or wall warts. I bought a Rigol DP832 power supply and I like the ability to dial in a current limit. Maybe I'll dial in 100 mA or something even less if I can. I like low energy circuits. LiPO batteries aren't low energy! They need to be handled with care. Alkaline AA and 9V are suitable for kids. They can make the smoke escape but they probably won't burn the house down. Probably...Those $5 Harbor Freight meters can be used as well. I helped my grandson do a science fair project of Ohm's Law using 3 of those cheap meters. He won first place! Surprised me, I didn't think anyone would care about electricity. Those cheap meters were perfect for the project.

author: ataradov
author_rank: Super Contributor
timestamp: July 17, 2018, 01:19:05 am
content: I would agree. HF meters are perfectly fine for this use. If you afraid of explosions - burn the fuses yourself, turn it into Fluke 101.

author: rstofer
author_rank: Super Contributor
timestamp: July 17, 2018, 02:00:00 am
content: Quote from: ataradov on July 16, 2018, 05:08:47 pmActually, I was a kid new to electronics, about 62 years ago. In the heyday of Heathkit, my folks bought me an a VOM kit - I was probably 10 when I built it and I still have it! Later on, I built a VTVM and a 10 MHz scope. Along the way were other kits. I guess I was "that kid...".It's unfortunate that Heathkit no longer exists. OTOH, it's fortunate that we can get things like Arduinos. The 555 timer hadn't even been invented when I was a kid. In fact, all of my projects were based on vacuum tubes. Transistors came along a bit later. Even in college, LEDs were brand new and memory was 16 4-bit words. I was clear into grad school before the 8080 hit the hobby market. The 2102 RAM (1k x 1) was just hitting the hobby market. A 4k memory board for the Altair 8800 was $400.Kids today have it pretty good. Even if their parents can provide only financial assistance, the Internet can provide everything else.

author: mtdoc
author_rank: Super Contributor
timestamp: July 17, 2018, 02:39:39 am
content: Yes, the Aneng 8008 lights up all colors of LEDs just great.The HF meters light up LEDs but have the major flaw of no continuity buzzer.

author: Mr. Scram
author_rank: Super Contributor
timestamp: July 17, 2018, 06:52:16 am
content: Quote from: Fungus on July 16, 2018, 10:19:12 amI don't call real world scenarios artificial. It really doesn't take a very steep angle to cause fading.

author: Fungus
author_rank: Super Contributor
timestamp: July 17, 2018, 01:43:51 pm
content: Quote from: mtdoc on July 17, 2018, 02:39:39 amSo does the ANENG 860B+, and it's a much better all-round meter, IMHO.(plus it uses normal-size fuses so you can easily put in higher-rated ceramics if you want)

author: mtdoc
author_rank: Super Contributor
timestamp: July 17, 2018, 08:07:37 pm
content: It looks like you can get a rebadgedAneng 8002 on Amazon for $12. So for about $30 you could get both one of those and a Brymen 136b and have the best of both worlds! - That's assuming the 8002 lights up LEDs like the 8008 does. Can anyone confirm this?

author: tooki
author_rank: Super Contributor
timestamp: July 18, 2018, 01:42:36 am
content: Quote from: ataradov on July 16, 2018, 05:57:30 amEither some models have awful LCDs, or you got a dud. My Aneng 8008 has better viewing angle and contrast than my 87V.