Aim-TTi 1908 5 1/2 Digit Benchtop Multimeter (preview) - Page 1
Forum section: electronics / testgear

author: kish
author_rank: Contributor
timestamp: September 01, 2020, 03:28:58 am
content: I was looking for a benchtop multimeter and I decided to buy theAim-TTi 19085 1/2 digit bench multimeter(datasheet)fromSaelig.I like the 1908 for its big, easy-to-read display. There's a dedicated physical button for each measurement type, without the need to press/hold shift buttons, or fuss with menu system.I think the most important part about a DMM is that it has to be clean and easy to use! Also: no fans! Completely silent.Designed & Made in England!(these images are clickable for full resolution)My current go-to multimeter is theFluke 87V, and while it's a great portable DMM, it has its downsides for me in a benchtop application.Primarily, while taking measurements on the bench, it's difficult to make readings while its laying flat on the bench. Propping it up is also annoying at times because the unit is tall, and has a tendency to fall over. My biggest issue is the backlight-- it keeps turning off and its annoying to keep pressing it to keep it awake.I considered several other DMM's in the 5 1/2 - 6 1/2 digit range. Unfortunately, all of them do have audible fan(s):1.Rigol DM3058E- 5 1/2 digit - (the display is too small, hard to read measurements)2.SIGLENT SDM3055- 5 1/2 digit - (great display, but slow sampling rate according to reviews)3.Keysight 34461A- 6 1/2 digit - (probably the best pick, but overkill for my uses. My 2nd pick)4.Fluke 8845A- 6 1/2 digit - (probably a very accurate DMM, but that display is terrible)There isn't too many reviews of the Aim-TTi 1908 on the internet (save for a single lonely review on Amazon). So first, some exterior views:(front)(front 3/4 view)(top view)(rear view)(Mine comes without the LAN/RS 232/GPIO interface. If you want those, you can get the slightly upgraded version, 1908P for a bit more.)(bottom view, fuse compartment)(easily accessible fuse holders)(display and buttons)(input terminals)I'll start with the coolest/unique feature of Aim-TTi 1908:(what's with this "charging" light...?)(that's right, it has a built-in Ni-MH battery for mains-free portable usage!)Probably the biggest downside about the 1908 is that, while it's a supposed 5 1/2 digit meter, it's only 120,000 counts! That means that 5 digits of precision at 11.9999V becomes 4 digits of precision at 12.000V.For example, the ranges are as follows:1V rangemin- 0.12000max- 1.1999910V (e.g. measuring 1.5V batt)min- 01.2000max- 11.9999100V range (e.g. measuring 12V batt)min- 012.000max- 119.9991000V (e.g. measuring 120V AC mains)min- 0120.00max- 1119.99So I personally don't know how to classiy this DMM. Precision-wise, I guess it's somewhere between a 4 1/2 digit and 5 1/2 digit DMM? In my opinion, it's misleading from Aim-TTi to market this as a "5 1/2 digit" DMM.For example, it's closest rival, SIGLENT SDM3055 is also a 5 1/2 digit DMM, but it has 240,000 counts, so it's a "true" 5 1/2 digit DMM. As I understand, a DMM needs to have at least 200,000 counts to be considered "5 1/2 digit". (0 or 1, followed by 5 digits of precision at all times)Here are some measurements I took in comparison with my Fluke 87V. I'm no Dave Jones with high precision calibrated equipment, but I try my best! By the way, the Fluke 87V is a 6000 count DMM. However, in high-resolution mode it can do up to 60,000 counts, I think. Thus, I gues the Aim-TTI is only 2x better at 120k counts?120V mains measurement:(Fluke in normal mode)(Fluke in high-res mode)1.19999V to 1.2000V range crossover point:11.9999V to 12.000V range crossover point:And lastly, I will mention it has several "dual measurement" modes. Here it is measuring DC voltage, and the AC component of DC voltage:I just got the unit so I'll need to read the manual and play around with it a bit more. There's a ton more technical info in the datasheet for those interested.Overall, I think it's a good unit for my hobbyist needs, and for anyone who can live with it's precision limitations. It's an an easy-to-use benchtop DMM, completely silent, and portable. It does have a very simple display, but that's also the beauty of it-- no fuss. I'd take function over form any day.If anyone wants me to testing anything specific, please let me know.

author: BravoV
author_rank: Super Contributor
timestamp: September 01, 2020, 04:09:07 am
content: Quote from: kish on September 01, 2020, 03:28:58 amTear down photos maybe ?

author: kish
author_rank: Contributor
timestamp: September 01, 2020, 04:30:49 am
content: Yes, I was afraid of that. Unfortunately that's the one thing I cannot doThis unit comes with a 3-year warranty from Aim-TTi. With the fuse compartment accessible from the outside, there's no good reason for an end-user to be poking on the inside.I also don't want to mess with the calibration by opening it (if that's a thing).

author: garrettm
author_rank: Frequent Contributor
timestamp: September 01, 2020, 05:23:02 am
content: QuoteYou need to be careful when you talk about precision. What you are really referring to isresolution, i.e. number of decimal digits. Precision is a metric that relates to the stability of the meter over time. The dart board analogy is often quite elucidating: You can be accurate, have darts hit a certain ring, but not be precise, darts are dispersed loosely all around the ring. You can be precise, darts closely clustered together, but also not very accurate, darts are far away from the bullseye.Unfortunately, programmers have used the word "precision" to imply the number of valid decimal digits stored in a floating point number and conflicts with terms used in metrology and sciences that involve physical measurements.To be honest 120000 counts is expected. Thats 100,000 counts with 20% overranging. Only a few instruments do 100% overrange (2,000,000 etc.) and even fewer that do 300,000 or 3,000,000 counts. So nothing unusual here. The "5.5 digits" on the front panel says it all: The most significant digit is limited, hence the 0.5 in 5.5.

author: J-R
author_rank: Super Contributor
timestamp: September 01, 2020, 05:26:23 am
content: Very nice preview, links and high quality photos.When shopping I also find the "digits" rating misleading and overly abused and hunt for the counts in the specs.But even the specs can be tricky to translate to the real world.For example, the Fluke 87V is sold as 6,000 counts normally and 20,000 counts in hi-res mode.In reality it can display 6600 so I consider it 6,600 count.It cannot display 20000, only 19999 so I consider it 19,999 count in hi-res mode.Counting up it switches at 6601 and going down it switches at 539.The "120..." count "issue" exists elsewhere. The 34401A is 1,200,000 counts, rated as 6.5 digit.

author: kish
author_rank: Contributor
timestamp: September 01, 2020, 05:47:20 am
content: Thanks! Yeah, some manufacturers are better at clearly disclosing the counts than others.For example, inSiglent'sline up, they're upfront and clear about their counts, right up in the header banner.On the other hand,Keysightis terrible at disclosing the counts. Nowhere on theirproduct pagefor the 34461A do they mention counts. Not even in theirdatasheet. Are we supposed to assume that 6 1/2 digits automatically guarantees at least 2,000,000 counts?Only on their entry level 5 1/2 digit DMM,Keysight U3400, do they mention the counts (120k). It's almost as if disclosing counts is only for cheaper DMMs.ToAim-TTi'scredit, they're quite upfront about their DMM being 120k counts, so I knew exactly what I was getting. If I had bought it expecting 200k, it would be a different story.> The "120..." count "issue" exists elsewhere. The 34401A is 1,200,000 counts, rated as 6.5 digit.That is interesting! How do you know this? Theirdatasheetdoesn't even mention the 1.2 mil counts.

author: kish
author_rank: Contributor
timestamp: September 01, 2020, 05:53:17 am
content: Quote from: garrettm on September 01, 2020, 05:23:02 amYes, I'm coming from a programming background, so it's only natural for me more digits = more precision.So to summarize your point, in regards to DMM's:Accuracy = how close the reading is to the actual valueResolution = precision (in general terms) = improves confidence in accuracyPrecision = how accurate the DMM's readings are over time (as internal electronics ages).

author: coromonadalix
author_rank: Super Contributor
timestamp: September 01, 2020, 05:55:00 am
content: I love Siglent with their "Real" digits loll

author: J-R
author_rank: Super Contributor
timestamp: September 01, 2020, 05:56:56 am
content: Quote from: kish on September 01, 2020, 05:47:20 amI tested mine and that is the maximum it can display, at least in DCV.

author: coromonadalix
author_rank: Super Contributor
timestamp: September 01, 2020, 05:59:54 am
content: For the 34401a this web site give you more specs ....https://www.atecorp.com/products/keysight-technologies/34401aLots of makers plays with the displayed digits vs resolution vs accuracy .... we love big numbers lollThe only 3,030,000 counts dmm i know are the keithley 196 and its Tektronix dm5120 brotherAnd Gossen Metrawatt 28 and 29s are 310,000 counts, 5 3/4 digits in a few modes and 4 3/4 digits in other modes ...Precision or Accuracy is another thing loll

author: J-R
author_rank: Super Contributor
timestamp: September 01, 2020, 06:08:42 am
content: The basic accuracy ratings are also abused as I found when comparing the U1282A and the U1461A. Sometimes you will see a very desirable percentage but with a large number of +/- digits and on the flip side a very poor percentage with very low +/- digits.Real world accuracy is also a factor as most of us would not accept a DMM that only just met it's published accuracy. For example if the U1282A were consistently say 8 counts out it would still be in spec but that would be terrible.

author: coromonadalix
author_rank: Super Contributor
timestamp: September 01, 2020, 06:14:32 am
content: Same for the many brymen / clones at 50,000 count and oh the 500,000 count mode lollThe high resolution vs the low / normal resolution .... they say, we had some war of words for that in past threads lollAnyway the OP TTI meter seems very nice clean and simple to useif he have'nt paid a fortune that's good enough for meSure a teardown would be nice loll and see what is the reference used ??

author: J-R
author_rank: Super Contributor
timestamp: September 01, 2020, 06:30:13 am
content: Quote from: coromonadalix on September 01, 2020, 06:14:32 amYes, that is perhaps a bit gimmicky...but also can be useful for certain purposes.As received my BM869s was frequently 100+ counts out in 500,000 count mode. After a quick calibration it is now never more than 15 and typically only 1-5.This does bring up the point that having digits on your DMM that can be trusted is as important as having the digits at all...

author: coromonadalix
author_rank: Super Contributor
timestamp: September 01, 2020, 06:51:48 am
content: Quote from: J-R on September 01, 2020, 06:30:13 am+1But the problems are to know when you can count on them, calibration is important, but sometimes its hard to justify it's pricing, luckily on some brand(s) you can make it yourselfMy flukes 189 cost 75$ cad to calibrate, my 34401a is 150$ cad and i'm not equiped with any references (resistors, ac or dc sources)The only precisions stuff i have, are some Fluke 343 left over boards with 0.035% resistors on them.

author: garrettm
author_rank: Frequent Contributor
timestamp: September 01, 2020, 06:58:06 am
content: QuotePretty close.Accuracy really represents the error bounds that the measurement is inside of. The meter could be spot on, or anywhere inside the bounds. But hopefully not on the edge, as that would imply a marginal meter.Resolution is the smallest value measureable in a given range. For instance, 100 nanovolts on the 100 mV range. But this implies number of digits, and this is how most people interpret resolution.Precision generally is interpreted as long term drift measured in PPM / year. It relates to how well a meter holds its calibration. A low precision instrument will drift more rapidly and need frequent adjustment to stay within its accuracy bounds. A precision instrument will hold its calibration for many years, rarely needing any adjustment at all.Calibration in general is not about adjusting an instrument. It is about creating a historical record of a meter's measurements vs primary standards. This then tells you the precision of the instrument and lets you know when the meter went outside its error bounds, at which point that range would need adjustment.It's a lot of jargon to take in, but hopefully that helps make sense of it all.

author: BravoV
author_rank: Super Contributor
timestamp: September 01, 2020, 07:13:21 am
content: Quote from: kish on September 01, 2020, 05:53:17 amA pic speaks thousands words ...

author: evava
author_rank: Regular Contributor
timestamp: September 01, 2020, 08:27:49 am
content: Quote from: kish on September 01, 2020, 03:28:58 amQuote(taken from other thread on this forum)

author: Fungus
author_rank: Super Contributor
timestamp: September 01, 2020, 09:02:20 am
content: Quote from: J-R on September 01, 2020, 06:30:13 amAt what temperature? Temperature starts to play a big role with that many digits. Raise it a degree and you might have 100 digits.No non-temperature-controlled meter is ever going to be 5 1/2 digits accurate but the digits are useful for seeing very small changes over time.

author: kish
author_rank: Contributor
timestamp: September 02, 2020, 02:33:49 am
content: One complaint that the Amazon reviewer had about this DMM is its high standby power, due to it constantly trickle charging its internal Ni-MH battery.With the rear (main) power switch on, and the front power switch off (standby mode), the unit draws2.4W. A standby power of 2.4W, is that good or bad?This is with a fully charged battery (front panel orange "charging" light is off). So, I don't think it's charging the battery at all. It would be poor design to constantly charge/keep the Ni-MH battery at 100%.According to the owner's manual:QuotePerhaps it's keeping some other circuits alive/"warmed up" for accurate measurements. When the unit is powered on (out of standby mode), it draws 3W from the wall.Regardless, it might be a good idea to put the meter on a bench power strip, and keep it turned off (if it won't be used for while), to avoid any standby power usage.

author: kish
author_rank: Contributor
timestamp: September 02, 2020, 03:40:55 am
content: It's interesting, in the owner's manual, it states that the scale length (aka resolution) is 5 1/4 digits (120,000 counts). So why not market this as a 5 1/4 digit DMM? Or is that not a thing?

author: garrettm
author_rank: Frequent Contributor
timestamp: September 02, 2020, 11:12:45 am
content: Quote from: kish on September 02, 2020, 03:40:55 amThat looks like a typo. It’s not uncommon to see errors in manuals or other product literature (I find them all the time).You can have different "fractional digits" for the MSD, but these are always larger than 1/2, not less. Nearly all manufacturers use 1/2 to imply the MSD is limited to 0 or 1 (or whatever the max value of the MSD is)--even if they could legitimately use a larger fractional digit to denote the MSD.I wouldn't pay too much mind to fractional digit notation, it's ultimately a pointless marketing gimmick. The more tactful approach is to state the FS counts to show that the MSD can go higher than 1. This is how HP marketed the 3457A DMM: 6.5 digits with 3,000,000 counts FS. Clear and simple.

author: JohnG
author_rank: Frequent Contributor
timestamp: September 02, 2020, 01:28:41 pm
content: Quote from: BravoV on September 01, 2020, 07:13:21 amI have never in all my life seen this definition for precision. What they call precision looks like noise to me or drift to me, depending on the applicable time scale.Cheers,John

author: nfmax
author_rank: Super Contributor
timestamp: September 02, 2020, 02:11:00 pm
content: The ISO/IECInternational vocabulary of metrologyISO Guide 99:2007 defines it thus:Quote

author: JohnG
author_rank: Frequent Contributor
timestamp: September 02, 2020, 02:48:53 pm
content: Quote from: nfmax on September 02, 2020, 02:11:00 pmWow, learn something new every day.I find the term "gauge reliability and repeatability" or gauge R&R to be more meaningful. The ISO standard definition is fairly vague, or, if you prefer, rather imprecise.Cheers,John

author: Fungus
author_rank: Super Contributor
timestamp: September 02, 2020, 03:44:33 pm
content: Quote from: JohnG on September 02, 2020, 01:28:41 pmAnd I've never seen the term "resolution" applied to a multimeter.Precision: Number of digits (or "counts" in the multimeter world - it might not have a range that's a perfectly round decimal number)Accuracy: How close those digits are to reality, often expressed as a percentage of readingandnumber of counts.eg. My Brymen in CD mode has 500,000 counts and 0.02%, 2 counts accuracy.Note that 0.02% of 500,000 is 100 counts so the meterisn'tclaiming that all those digits are accurate.(although in practice they're usually very close to those 2 counts...that's digital calibration for you!)

author: voltsandjolts
author_rank: Unknown
timestamp: September 02, 2020, 04:15:50 pm
content: Quote from: Fungus on September 02, 2020, 03:44:33 pmMaybe you have never looked for it

author: kish
author_rank: Contributor
timestamp: September 02, 2020, 11:47:23 pm
content: Quote from: Fungus on September 02, 2020, 03:44:33 pmSo essentially, your Brymen is 5,000 count DMM(since the least significant 100 counts cannot be trusted, in 500k count mode)

author: 2N3055
author_rank: Super Contributor
timestamp: September 03, 2020, 06:57:33 am
content: Quote from: kish on September 02, 2020, 11:47:23 pmAnd by your logic very expensive Keysight 34460a is 1200 count DMM because in 100 MOHm range it has 0.8% accuracy spec.Or the legendary HP3458 is really 5.5 digit meter because best version has only 4 ppm/year accuracy spec, so you can't trust anything that is less than 10 ppm of reading on it, right? No, not really. Unfortunately, it is bit more complicated than that.There is a reason why manufacturers give you specifications table. On every single meter, on every single measurement and every single range you have some (different) accuracy specification. It is user that has to know them all and know how and when to apply them.

author: J-R
author_rank: Super Contributor
timestamp: September 03, 2020, 07:00:25 am
content: Quote from: Fungus on September 01, 2020, 09:02:20 amNo, it is not that bad once calibrated, which is trivial to do for for the 5V range since there are so many easy to obtain 5V references.For the 15 count and 1-5 count stats I mentioned, that is for a relatively stable operating temperature of a degree or two in either direction combined with first turn on vs. extended use. For low voltages far from the calibration point, such as 1V, (or 10V with the 50V range) it is very solid and that is where many times it is only a few counts out.As a quick test I just did another 5V DC calibration at 70F and then tested the meter at 65F and 75F. In that case it was about 30 counts off in either direction.At 40F it was about 85 counts low, at 10F it was over 250 counts low.So I think if you purchase the BM869s, buy a known 5V standard as well and you will be in better shape to utilize the full 500,000 counts.Probably no surprise to anyone, my U1461A in 66,000 count mode with the factory calibration was about 5 counts high at 6V at 70F, basically spot on at 40F and about 5 counts low at 10F.

author: Fungus
author_rank: Super Contributor
timestamp: September 03, 2020, 07:06:30 am
content: Quote from: kish on September 02, 2020, 11:47:23 pmNo, it's a 500,000countDMM.Quote from: J-R on September 03, 2020, 07:00:25 amWell... mine's a BM857s but the same thing applies.I've got a 10V/7.5V/5V/2.5V standard that's calibrated to 4 decimal places. The meter agrees to within a digit or two so that would make it about 0.002% accurate (an order of magnitude better than the paper specs) and in normal 50,000 count mode it's accurate down to the last digit (plus or minus a couple of counts).

author: J-R
author_rank: Super Contributor
timestamp: September 03, 2020, 07:26:08 am
content: Quote from: 2N3055 on September 03, 2020, 06:57:33 amI think that is the point he is making, looking at the published specs you could not really trust the meter much. For my BM869s, that was my gripe, the DMM met specs so could not be sent back under a warranty claim, but in reality nobody in their right mind would accept 5.00112V in 500,000 count mode or 5.0011V in 50,000 count mode. No better than some of my 6,000 count DMMs.For example:https://www.eevblog.com/forum/testgear/brymen-bm869-and-bm867-batch-calibration-check/BM869 #1 reads 4 counts high, 5.0004V. So really you can only utilize 5.000V because the 4 is clearly "incorrect". My BM235 displays exactly 5.000V for 5.00000V, for example. So the BM869s has no use in this specific case.For only tracking changes, then it is not as much of an issue, so I am just focusing on the absolute values here.Another plug for the DMMCheck Plus, which now has a Capacitance Reference Board option. For anyone who has a mid-low range DMM I think it's a good thing to have.

author: bd139
author_rank: Super Contributor
timestamp: September 03, 2020, 07:35:54 am
content: Great review. Can you let us know how the continuity is on it. A lot of the earlier TTi meters had an abysmal implementation.There are quite a few TTi fans in here. They make decent equipment at a not too scary price.

author: eevcandies
author_rank: Regular Contributor
timestamp: September 03, 2020, 08:59:44 am
content: you gotta watch res vs accuracy...i have plenty of res, but the accuracy is only maybe 5-8 ppm

author: kish
author_rank: Contributor
timestamp: September 03, 2020, 09:13:19 am
content: Quote from: bd139 on September 03, 2020, 07:35:54 amWhat would you like to know, specifically? I don't have a function generator, so I can't test duty cycle response (Hz).But latching speed is quite good, when testing manually via probes. I would say it's on par with my Fluke 87V. I'm using Probe Master 8000-series test leads. I haven't tried the stock leads yet.From the owner's manual:Quote

author: Fungus
author_rank: Super Contributor
timestamp: September 03, 2020, 09:24:36 am
content: Quote from: J-R on September 03, 2020, 07:26:08 amThat's true for a randomly chosen meter, buuuut ... if it'syourmeter that you use every day and have cross-checked against voltage references and other meters then you can know exactly how much to trust the numbers on screen.Plus: A digitally calibrated meter with lots of digits should always beat a 6000 count meter in real life.

author: coromonadalix
author_rank: Super Contributor
timestamp: September 03, 2020, 10:26:48 am
content: +1 fungus, you have up to 12 digits meter for tons of $$$ for metrology purposesIf a 6000 count dmm was this precise, all 4.5, 5.5, 6.5, 7.5, 8.5 and more digits would be useless, i would love to see the meter internal reference used lolll maybe an ltz1000 ?My 34401a would cry

author: kish
author_rank: Contributor
timestamp: September 10, 2020, 12:39:55 am
content: Today, I'm looking at the temperature measurement capabilities of the Aim-TTi 1908.The unit can be used withPT100thermistors in 2-wire or 4-wire configuration, or withPT1000thermistors in 2-wire or 4-wire configuration. It can measure from -50C to 400C with either thermistor. The accuracy is 0.05% +- 0.5C:Ideally, I wanted to get a 4-wire PT1000 thermistor for the highest accuracy, but those are difficult to find at an affordable price. After some research, I found out that 4-wires aren't as important with PT1000 due to the higher resolution it provides, so I went with a PT1000.I picked up anAtlas Scientific PT1000 temp probe(datasheet), plus a BNC to banana adapter.As far as accuracy goes, how is that calculated? Does the error from the DMM (0.05% +- 0.5C) add linearly with the thermistor accuracy (0.15%)?Before measuring, I first went into the utilities menu and changed the temp reading mode to 2-wire (defaults to 4-wire).Then you hit temp option and hit right to go into PT1000 mode. Here is the temperature reading at room temp, seems "about right":In Farenheit:In Celcius:As far as high temperature measurements, my plan was to test the probe against my TS100 soldering tip set to 200-400C.Unfortunately, even with the fattest tip for the largest surface area, and me pushing down hard as I can, the temp was rising very slowly (0.1C per 1 sec). After quite some time, it settled and wasn't able to measure higher than 100-120C (with iron at 400C):I know for a fact that the temp reading on the TS100 soldering iron is fairly accurate by using it over the years. It also melts solder like butter. Perhaps either the DMM is faulty, or the thermistor is faulty, or I'm just doing something wrong.As as sanity check, I switched to 2-wire resistance mode while measuring temp, and the resistance values were correct (e.g. ~1250 ohms at 64C).Temp calculation equation:

author: Thomas
author_rank: Regular Contributor
timestamp: September 10, 2020, 10:37:50 am
content: You won't be able to heat that hunk of metal with a soldering iron tip. There will be a (small) gap between the sensor and the thermowell, which doesn't help either.Have you tried without the thermowell?

author: 2N3055
author_rank: Super Contributor
timestamp: September 10, 2020, 01:37:52 pm
content: Test with boiling water.. Water have thermal capacity needed.

author: kish
author_rank: Contributor
timestamp: September 10, 2020, 06:16:50 pm
content: Quote from: Thomas on September 10, 2020, 10:37:50 amYeah, these results (except the ambient) are without the thermowell, soldering tip directly against the thermistor metal can. With the thermowell, it takes even longer to heat up (understandably so).

author: Thomas
author_rank: Regular Contributor
timestamp: September 11, 2020, 10:41:17 am
content: Yep, that makes sense.For measuring soldering iron tip temperature, you'll need a small mass sensor.Accuracy errors are added, because both can be on the edge of their spec, in the same "direction".Not very likely, but itcanhappen.

author: voltsandjolts
author_rank: Unknown
timestamp: May 22, 2021, 04:32:55 pm
content: I bought the TTi1908P, with the ethernet and GPIB interfaces.Really it was the battery option that sold it to me. I do 90% bench work and the battery covers me for the rest.First impression, out of the box, it really does feel like a quality bit of kit.Nice metal enclosure, buttons feel good and the display is clear with good viewing angles.Safety fuses are accessed via a small 'hatch' on the underside.Can't see any 'warranty void if broken' labels...just two screws to undo at the back and the lid comes off.PCB assembly is a tidy build. Gold plated board, brand-name components.Chunky vishay in-guard/out-guard isolators, NXP MCUs, dale and caddock resistors.AC RMS converter under the shield includes AD8436.ADC is TI ADS1246 24bit sigma-delta, using 2.5V reference provided by a SOT23-5 marked ACQD == MAX6071AAUT25Better put it back together and try using now

author: voltsandjolts
author_rank: Unknown
timestamp: June 21, 2021, 10:24:53 am
content: So far I only have two negative comments about this meter;1/ The 500 datapoint log memory is way undersize for this day and age. Was it actually worth the effort implementing all the firmware to support datalogging and only have 500 datapoints?2/ The TTi PC Software is not great, functional on Windows for getting readings and retrieving log data to CSV but the charting is laughably bad.To help with this, I wrote a 1908 driver for the popular Test Controller software which is available on this forum.The driver will hopefully be included in the next release, until then just drop the TTi1908.txt file into the drivers sub directory.Test Controller here:https://www.eevblog.com/forum/testgear/program-that-can-log-from-many-multimeters/msg2981004/#msg2981004Driver submission is here:https://www.eevblog.com/forum/testgear/program-that-can-log-from-many-multimeters/msg3591749/#msg3591749To begin, run Test Controller then go to load devices tab, click ADD button and find TTi1908.Edit the COM port / tty appropriately. Baud rate doesn't matter, the 1908 implements CDC but ignores baud rate.Click RECONNECT and the 1908 should go into remote mode.On the command tab click MODE and select the meter mode you want VAC/VDC/.. etc.Live readings should now be available, to log and chart data click the LOG button and select the log rate.

author: gamalot
author_rank: Super Contributor
timestamp: June 21, 2021, 10:58:48 am
content: Quote from: eevcandies on September 03, 2020, 08:59:44 amI have this NF WF1946B function generator too, and my wife said it is the most beautiful one of my 50+ benchtop test and measurement equipment.

author: voltsandjolts
author_rank: Unknown
timestamp: June 28, 2021, 10:15:39 am
content: Support for this DMM is now included in Test Controller V1.7Download link at the bottom of this page:http://lygte-info.dk/project/TestControllerIntro%20UK.html

author: voltsandjolts
author_rank: Unknown
timestamp: October 12, 2021, 12:24:38 pm
content: Something to be aware of with this meter is the lack of jack detection on the current inputs.This means there is no warning (on display or from buzzer) when you've selected a non-current range but leads are connected to the current jacks.Same when you select the 10A range but leads are in the 1A/mA jack.So far, I've been lucky but one day....

author: Kleinstein
author_rank: Super Contributor
timestamp: October 12, 2021, 12:53:03 pm
content: Jack detection is not common with bench meters. There is at lest 1 that at least uses LEDs (as some kind of ring at the terminals) to indicate which terminals to use. This is nice, but the exception.Some of the bench meter allow to use amps and volts more or less simultaneous, though with reduced accuracy from a common terminal.

author: voltsandjolts
author_rank: Unknown
timestamp: October 12, 2021, 01:42:27 pm
content: I generally use this meter running from the internal battery, using it as a replacement for a handheld DMM, and had that mindset here so hence my quibble.Need to re-train the brain!

author: PeterKlop
author_rank: Contributor
timestamp: December 28, 2021, 11:55:41 pm
content: Hi.I was wondering.The display of this meter looks like really low contrast with the blue numbers on the blue background. The fluke meter has much more contrast in these pictures. Are these pictures representative for what you see with your own eyes?If you don't mind i ask you this question because you have bought the meter and the thread starter (kish) doesn't seem te be active on the forum anymore.How do you like the display?Kind regards,Peter

author: voltsandjolts
author_rank: Unknown
timestamp: January 04, 2022, 03:16:09 pm
content: Hi Peter,I bought my meter in May 2021 and the display is not blue at all.With the backlight off it looks like "standard" LCD (contrast is OK in daylight).With the backlight on digits look black against white background and contrast is excellent.On a web search, I could not see any blue display versions...maybe it was an older fitment?To my eye, the contrast looks just like the attached picture.

author: PeterKlop
author_rank: Contributor
timestamp: January 04, 2022, 05:32:18 pm
content: Thanks for the info!I was refering to the pictures in the first post of this thread and also later ones from use Kish and also some youtube vids i saw.There was one up for sale on ebay for €350 and i was wondering whether or not i should buy it.I didn't namely because of the doubts i had about the display and now it's gone. So now i regret my decision. Oh well.The price for a new one is €650 over here and that's a little bit more then i was planning to spend on my third meter. Yes i don't really need itit's a case of gas and i like this aim-tti.

author: voltsandjolts
author_rank: Unknown
timestamp: January 08, 2022, 02:03:12 pm
content: Ahh, OK. I guess the photos from Kish show blue-ish backlight due to some camera artefact.I see the 87V display also looks a little blue, but is actually white also.