Shannon ST42 LCR Tweezer Test and Comparison Thread - Page 1
Forum section: electronics / testgear

author: Martin72
author_rank: Super Contributor
timestamp: June 16, 2024, 09:46:19 pm
content: Hi,LCR measuring tweezers, to which the greatest things are attributed, as the sole miracle tool that makes other LCR superfluous, where some people never tire of bringing them into play in every purchase advice....something like that makes me curious in principle.So I bought one from Aliexpress and it should arrive next week.In addition to an incoming inspection in terms of appearance and manufacturing quality, the main component will of course be measurements.I have thought of the following steps:- Measurements on the DMM Plus Check reference, more precisely on its LCR option.- Comparative measurements with the following devices:Mastech LCR tweezersET4410 Benchtop LCR MeterET4510 Benchtop LCR MeterSourcetronic ST2830 Benchtop LCR Meter, calibratedAgilent U1733C Handheld LCR Meter, calibrated.GWInstek Milli-Ohm Meter, calibrated.- Comparison measurements on components that are already integrated in a circuit.- Comparison measurements cold start/ after a warm-up time.The latter because it was said that with other devices you have to wait until they meet the tolerance.I maintain that it doesn't matter.We'll see.Furthermore, an attempt to see what maximum component size can still be measured mechanically without using aids such as wire extensions, which of course distort the result.And one more thing, measurements on coils with a core, if their size allows it.This could be interesting insofar as the measuring voltage of the ST42 is rather low.I'm curious to see how it performs.Why am I opening this thread now?To collect further ideas, if you think of anything else, post it here.Next post will follow when the ST42 has arrived.Martin

author: tautech
author_rank: Super Contributor
timestamp: June 16, 2024, 10:07:15 pm
content: QuoteYou missed speed of measurement and speed of use = convenience at the bench for the majority of tasks.

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 16, 2024, 10:17:18 pm
content: Quote from: Martin72 on June 16, 2024, 09:46:19 pmI agree, I don't actually usually wait the 30 minutes for the bench meter either, unless it's for something that really matters. Which is rare. 😉However, you can often finish measuring with the ST42 by the time the bench meter goes from power on to ready even without warmup.QuoteIf you leave the wire aids on, you can run calibration with the wires as part of the device to compensate for them...but you already know this. 😉

author: Hydron
author_rank: Super Contributor
timestamp: June 16, 2024, 10:28:28 pm
content: Quote from: tautech on June 16, 2024, 10:07:15 pm+1 to this - the reason I never pick up my Mastech tweezers isn't due to any inaccuracy etc, it's that they are just so much worse ergonomically and speed wise compared to the ST42. You're not buying standalone SMD tweezers for top end specs, you're getting them for convenience (though obviously the more accuracy the better, and I look forward to seeing the numbers).

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 16, 2024, 10:33:21 pm
content: I'll run some new comparison tests soon too. Here's the old result when I still had buggy firmware on my bench meter. The ST42 was very helpful with sanity checks.

author: Martin72
author_rank: Super Contributor
timestamp: June 16, 2024, 11:03:05 pm
content: Measuring speed ? Are you in a hurry guys ?

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 17, 2024, 12:43:21 am
content: Yes!The PCBs with SMT I was building last week had 16 of the same part on each of the 3 boards. I don't want to spend 2 hours measuring 48 of the same component before I could continue testing/installing parts.

author: Martin72
author_rank: Super Contributor
timestamp: June 18, 2024, 10:16:41 pm
content: QuoteYou don't have to....The warm-up time is to be regarded as a standardization.An LCR meter may well need 20 to 30 minutes (the more complex the design, the more) to be able to measure within itsowntolerance.But who cares about a basic accuracy of say 0.05% if the components to be measured have a tolerance of 5% or more....In other words, if it is necessary to select components with an accuracy of 0.05%, then there is something wrong with the circuit.Or to put it another way, if the ST42 reaches its own tolerance significantly shorter, it is only because significantly fewer circuits have to be thermally balanced.All theory is gray, it's the practice that counts.

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 19, 2024, 01:02:21 am
content: Quote from: Martin72 on June 18, 2024, 10:16:41 pmI know, but you're forgetting two things: 1. I don't have a tweezer attachment for my bench LCR because anything good costs more than the ST42 for me; and 2. I don't want the reduced mobility of being tethered to the bench meter.So the ST42 works faster, and with better mobility. Also, the regular startup time from powering on the bench LCR to the point that it's ready without warmup is still long enough to be measuring a few components already with the tweezers.Without the overpriced tweezer attachment, the bench LCR takes hours to test SMT stuff. For the first round of LCR comparison/firmware tests I hadn't designed my test PCBs yet. It literally took hours to mount and test all the SMT components on the SMT fixture. It took minutes with the tweezers.I'm going to order a new version of my test board so I can also test step dissipation factor now that I know how to do that. I'll share a new comparison when I'm done.

author: Cyclotron
author_rank: Unknown
timestamp: June 19, 2024, 05:03:04 am
content: I'm certainly interested in your testing results. Testing and comparing to other devices seems reasonable.I see folks being given recommendations based on their requirements. People are encouraged to develop or have requirements.My needs were straightforward. I simply required an instrument to swiftly assess components during repair triage. Based on my experience, I would confidently recommend these tweezers to others with similar needs.That said, I can imagine there are a lot of objective tests that can be done, and I do look forward to reading the results, but I don't know how that will impact the subjective recommendations that are made to people. Obviously, if you have findings that show a better solution at comparable pricing that fits my needs, I'm all ears.

author: Overspeed
author_rank: Frequent Contributor
timestamp: June 19, 2024, 06:20:06 am
content: Quote from: Martin72 on June 18, 2024, 10:16:41 pmHelloAccuracy is the result of the sum of the uncertainties so accuracy of a component need to be separate from the accuracy of measuring equipmentThere is several use for a LCR or even a ohmmeter_ Sorting component in the same ''precision quality so reject the extremes values / out of tolerances values_ Matching components in pair , triple ... as capacitor in parallel_ Select component to catch the closest perfect nominal value_ Identify component with out engraving valueA very good test of a Quality setup which include a measuring equipment is to run an ANOVA R&R testRegardsOS

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 19, 2024, 02:10:38 pm
content: Quote from: Cyclotron on June 19, 2024, 05:03:04 amI've already done comparison tests (which I'll be diving deeper into again soon when I receive my new test PCBs), but the tweezers performed exactly as they're supposed to. I think part of the point is that there really isn't much to compare within the price point. These tweezers are as good better than tweezers that cost 3x as much. They also held their own (and helped correct bad fw) in bench meters that cost 10 to 20x as much.I think if somebody has some of those overpriced Canadian tweezers to compare to, that would be great.

author: BirdManPhil
author_rank: Contributor
timestamp: June 19, 2024, 02:38:23 pm
content: Are there any tweezers that can measure caps as low as 0.1pf with a resolution that works for this? I see shannon st42 bottoms out at 0.3 or 0.5 pf

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 19, 2024, 02:43:26 pm
content: Quote from: BirdManPhil on June 19, 2024, 02:38:23 pmI'd be a little surprised, but maybe. Even our expensive bench meters doesn't claim accuracy below 1pF.

author: Martin72
author_rank: Super Contributor
timestamp: June 19, 2024, 02:59:20 pm
content: At less than 1pF, you are also more likely to be in the parasitic range where you are measuring something.

author: BirdManPhil
author_rank: Contributor
timestamp: June 19, 2024, 03:57:23 pm
content: That sucks. Maybe this would be a good complement to the tweezers thenhttps://www.szmatrix.com/products/digital-lcr-meter?Am I mistaken or does that seem to have the accuracy I'm looking for?

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 19, 2024, 04:02:49 pm
content: Quote from: BirdManPhil on June 19, 2024, 03:57:23 pmDisplay range and accuracy aren't the same thing. That device is much lower end the the ST2832 I shared the accuracy chart for.

author: TomKatt
author_rank: Frequent Contributor
timestamp: June 19, 2024, 04:27:03 pm
content: Quote from: BirdManPhil on June 19, 2024, 03:57:23 pmI question the ability toaccuratelymeasure the 0.0001 pf stated in that devices spec sheet.

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 19, 2024, 04:31:21 pm
content: Agreed, certainly not on that meter.At 200kHz the ST2832 can measure 10fF (the pF is a typo on the chart in that position top right corner), but that's in it's lowest accuracy range.

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 19, 2024, 04:43:22 pm
content: If you want to spend $20,000 on an LCR, you can get into the fF range better, but still probably 5% accuracy at best.

author: Overspeed
author_rank: Frequent Contributor
timestamp: June 19, 2024, 06:28:22 pm
content: HelloAn Hioki online calculatorhttps://www.hioki.com/e/products/lcr/im_calc_accur/a IET LCR comparisonhttps://www.ietlabs.com/basic-accuracy-of-an-lcr-meterI am not an expert in LCR but in all test equipment price follow the performance .

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 19, 2024, 06:57:31 pm
content: According to Hioki's Range chart (not accuracy) they have very limited coverage below 1pF on the IM3536, which appears to be their best option currently.

author: BirdManPhil
author_rank: Contributor
timestamp: June 19, 2024, 08:00:58 pm
content: Do I have to spend 20k just to test a 0.1uf cap though...

author: tautech
author_rank: Super Contributor
timestamp: June 19, 2024, 08:04:16 pm
content: Quote from: KungFuJosh on June 19, 2024, 02:10:38 pmThere is but they are junk.QuoteThis ^QuoteI have.ST3 that are nearly 20yrs old < now retired in favour of the far better ST42.A ST5 variant has regularly been of interest as a replacement to ST3 but not at that price.

author: Martin72
author_rank: Super Contributor
timestamp: June 19, 2024, 08:30:42 pm
content: In the meantime, I had taken a look at Shannon's website.But it doesn't say much about the ST42, I would have expected more technical details.The accuracies given there are sufficiently low for C and L, but for R it could sometimes be too much for precision resistors.However, these would be exceptions, before we get too excited.The website was last updated in 2022, the corresponding firmware available there is also 2 years old, there was probably nothing more to improve.Although I ordered the ST42 later than the ET4510, I assume that it will arrive sooner because customs formalities are no longer necessary.

author: tautech
author_rank: Super Contributor
timestamp: June 19, 2024, 08:41:16 pm
content: Quote from: Martin72 on June 19, 2024, 08:30:42 pmYet Shannon invites us to join the ST42 discussion on EEVblog where the OP was updated: Last Edit: May 06, 2024, 03:06:27 am by ShannonIn this thread Josh updated to fw v1.5.4 early June but it seems there is not a website link to it.Josh, how did you source fw v1.5.4 ?Not that it worries me as the units I have coming will all have this FW installed.

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 19, 2024, 08:55:45 pm
content: Quote from: tautech on June 19, 2024, 08:41:16 pmUsing the OTA firmware update tool, it will automatically pull the latest firmware if you don't specify a version. You need to open a command prompt or shell, then do updaterfilename COMport and it will run the update for you. I renamed it to fwu.exe so I did.\fwu.exe com8for my tweezers.I'm also likely to sell the ST42 to the US market directly, but if/when that happens, I will do a firmware update and quick test on his test board before shipping tweezers out to make sure nothing is defective.

author: Martin72
author_rank: Super Contributor
timestamp: June 28, 2024, 05:19:24 pm
content: It finally arrived today, picked it up earlier.Nice and small, you can't say otherwise.The build quality, however, is rather... "robust".You shouldn't look at it very closely, the opening for the display, for example, looks as if someone has nibbled it out.But as is almost always the case, it's the inner values that count and I'll be testing them out soon.First at home and against LCRs, which are here."Unfortunately" I'm on vacation now, so a test against calibrated devices will take some time.But that won't stop me from posting the results of the home tests beforehand.I'll fully charge the ST42 for now...Oh yes, there was a note saying that some spare screws/tips were "hidden" in the case, I didn't find any of them.

author: TomKatt
author_rank: Frequent Contributor
timestamp: June 28, 2024, 05:48:02 pm
content: I just received an email indicating that my order has been delivered to my post office box awaiting pickup on my way home this afternoon :-) I placed my order on 6/17, so shipping to the US was much quicker than I expected. I do not order from Aliexpress very often - didn't really expect any problems but very happy with how smoothly the order went through.Very excited

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 28, 2024, 06:06:30 pm
content: I received my new test PCB. I'll have the parts order in on Monday, and then I'll run a bunch of tests too. Including the ST42, ST2832, and probably also my Siglent bench DMMs. Maybe also the DE5000.

author: Martin72
author_rank: Super Contributor
timestamp: June 28, 2024, 07:39:31 pm
content: The display looks good, OLED is simply hard to beat.The information about charging is also nice.

author: Martin72
author_rank: Super Contributor
timestamp: June 28, 2024, 10:00:35 pm
content: Quote from: KungFuJosh on June 28, 2024, 06:06:30 pmThis would be a good opportunity to have your TH2832 calibrated.If its basic accuracy (0.05% is excellent, it could hardly be better) is confirmed, you can measure your board and the values determined would then actually have reference status, as your other LCRs are clearly above the accuracy of the TH2832, especially the ST42.

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 28, 2024, 10:10:40 pm
content: Quote from: Martin72 on June 28, 2024, 10:00:35 pmI think my ST2832 cal hasn't expired yet. I don't really know where I would send it for calibration anyway when the time comes...which will also be based on the test board to see if it still agrees, or drifts too much. I don't really have a need for a certificate beyond saying that it has a certificate on here. 😉

author: Martin72
author_rank: Super Contributor
timestamp: June 28, 2024, 10:44:39 pm
content: QuoteYou had turned your 2830 into a 2832, so there is no longer any question as to whether.QuoteYou take the trouble to design a test board and equip it with components that have a value and a tolerance.This means that the respective value can vary, and if you are unlucky it will be out of tolerance.To be able to determine this properly, you need a measuring instrument of which you know where its own tolerance lies.And this must be documented.Factory calibrations are not to be trusted at first, if you want to use a device as a reference, you should have it "neutrally" calibrated.QuoteThen you don't need to buy a measuring device, which is very accurate according to the manufacturer's specifications; a guessing tool will suffice.Now seriously.I buy brand A because it's supposed to be accurate, but I'm not really interested in whether it's really that accurate, the main thing is that it shows something I expect.I may see it too narrowly, because I have been checking things professionally for over 20 years and have to provide corresponding proof that everything is correct.Either way, it's not my thing.My problem, no question.

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 28, 2024, 10:56:58 pm
content: Sure, but I could get the ST2832 certified...if I knew where to have it done. Or I could have my test board certified. Or both. But either way, I don't know where to have it done. I'm also not willing to spend $500 for certification of either.Quote from: Martin72 on June 28, 2024, 10:44:39 pmI get what you're saying, but that was not really different than a firmware update. Most home users don't recertify with every firmware update. 😉

author: Martin72
author_rank: Super Contributor
timestamp: June 28, 2024, 11:17:47 pm
content: Your measurement frequency has doubled, the calibration referred to the maximum frequency before the "upgrade".QuoteI don't know your situation in the states, but I have easily 4...5 calibration laboratories in the vicinity.I had my Brymen 869S calibrated for 79€, my SDM3065X would cost just under 150, an LCR meter a little over 100.A recalibration of my DMM Check Plus Board also costs 79€.If the ET3502 convinces me, I will definitely have it calibrated, I'm still thinking about the ST42, depending on whether it convinces me too.A first R measurement earlier was rather sobering.

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 28, 2024, 11:47:25 pm
content: You're lucky then. Trescal is who SiglentNA prefers for real cal, and they're not cheap, or local to me. The closest is at least a couple hundred miles. So then there's shipping costs added to it.There are possibly a few others in my state, but nothing less than about an hour drive.Basically, if I don't see any indication of issues, I probably won't waste any time or money on it. If 5 meters agree on a bunch of 0.1% resistors, that'sprobablygood enough.ETA: I emailed a couple labs in my state to see what their rates and capabilities are. I'd be impressed if they come back with anything reasonable. 😉

author: TomKatt
author_rank: Frequent Contributor
timestamp: June 29, 2024, 04:30:20 pm
content: I'm just a simple hobbyist, so 'real' calibration is beyond my budget - the best I can hope to attain is reasonable accuracy achieved by purchasing what I perceive to be the most reliable tools combined with some common sense of the readings I get and comparing those results to any other gear I have.Anyhoo, I just recieved my set of ST42 Tweezers and my initial impressions are excellent - these tweezers look and feel like a high quality tool. They have just enough weight in the hand so they don't feel 'cheap', yet not so much as to be unconfutable using them. The oled display is excellent - very sharp and readable. Despite the small screen size there is a lot of information and it is easily read at board distance. The Hold function works well, but that setting seems to reset every power cycle? I'm still learning the menu system, which although is easy to use does have a lot of options.I did order the optional curved blade tips, but now that I have the tweezers in my hand I'm not sure if I really needed them. There was a note in the box indicating that the tips and a set of spare screws were inside the case. But in the excitement of receiving the package at the post office I could not resist opening the box in my car - Imayhave lost the screws in that process... The tips were wedged between the foam and case side, but I did not find any screws - I only seeonesmall plastic insulator type bead... I'm not sure if I lost parts or if that insulator is needed - the tips that came attached to the tweezers do not appear to have this insulator on the screws. Not really a huge deal, but it would be nice to have a list of all the parts in the kit so I could verify everything was accounted for. A photo attached below shows the insulator bead - if anyone else knows what that is for I'd be appreciative.The calibration board is nice - both as a learning tool and also a sanity check for readings. I haven't had a lot of time to play around with calibration, but as a first pass out of the box every component on the calibration board measured within a fraction of 1%. Again, I have nothing to validate those results at this time but they do seem reasonable.All in all I am very happy with this purchase - while I don't do a lot of smd work these are still very helpful for boards stuffed with components and are a lot easier to use than test probes in those cases.Edit - forgot to mention that my purchase was motivated by the desire to obtain an LCR type meter to add to my bench. I considered the DE-5000 that seems widely respected, but these tweezers looked to provide much of that functionality while also being useful for work on cramped boards. Also, I got the sense that the DE-5000 tweezers were lacking and everyone seems to be hacking togther some kind of Kelvin clips for that meter... I figured why noyt just get smart tweezers instead?Edit 2 - In addition to a list of parts included in the package, it might be helpful to enclose any optional small parts (tips, screws, insulators?) in a small bag or similar package so they are not loose in the case. The tips aren't likely to go far, but if there were screws inside my case they are the size of a grain of rice and very easily lost...

author: Martin72
author_rank: Super Contributor
timestamp: June 30, 2024, 08:07:18 pm
content: I held the tweezers to the inductances of the DMM Check plus earlier.There are probably some problems with small inductances, see 1µH and 10µH.I then activated the self-calibration, the -1.3µH then becomes 1.2µH.With the 8.1µH the "correct" value of 10.4µH.100µH and 1mH agree well.

author: Martin72
author_rank: Super Contributor
timestamp: June 30, 2024, 09:00:43 pm
content: After I calibrated again (open/short) and ran the selfcal routine as before, the results are as follows.(10kHz, 0.5V) (ref)Inductance:1.12µH (1.061µH) +5.5%10.56µH (10.52µH) +0.4%104.0µH (104.3µH) -0.3%1.040mH (1.032mH) +0.8%Capacity:1.019nF (1.019nF) 010.16nF (10.16nF) 0102.3nF (102.5nF) -0.2%1.037µF (1.001µF) +3.6%Resistance(RDC):99.98 Ohm (100.058) -0.6%998.5 Ohm (999.4) -0.1%10.00kOhm (9.9995k) +0.01%100.0kOhm (100.017k) -0.02%Apart from the two clear slips, these are very good results for a device of this simple design.The fact that it is better to calibrate it beforehand makes it clear that you can't just use it quickly if you want to rely on the results.But then you can trust the measurements almost blindly, and the fast display is also pleasant.

author: KungFuJosh
author_rank: Super Contributor
timestamp: June 30, 2024, 09:47:59 pm
content: I wonder how much of an effect aging has with these. My tweezers are over 2 years old. I'm looking forward to my new comparison this week.

author: Martin72
author_rank: Super Contributor
timestamp: June 30, 2024, 10:18:02 pm
content: If you want to know exactly, you would have to access the objects you measured 2 years ago with the tweezers and measure them again.But you can start again now and then every 6 months....The accuracy of the ST42 is not outstanding, rather worthy of the price, but in practice this should hardly play a role.Even the 5.5% deviation at the smallest L value is hardly relevant in my opinion, even if it far exceeds the tolerance specified by the manufacturer.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 01, 2024, 02:01:40 pm
content: I was more referring to my measurements being closer to the bench LCR. Stuff should arrive today for the test PCB, we'll see how it all looks.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 02, 2024, 11:05:26 pm
content: I forgot how tedious these cal tests are. Here's a PDF with the results of the ST2832 and ST42. On the bright side, my estimates for calculating dissipation factor were pretty darn close.I decided against making it take twice as long and including other meters. In the future, if I make a LCR test board that I really like, I'll get it calibrated and then do one test with all my LCR meters. I need to devise a better way to connect the kelvin clips, it's very picky about position.EDIT: Corrected test voltages on PDF.

author: Martin72
author_rank: Super Contributor
timestamp: July 02, 2024, 11:14:03 pm
content: I have downloaded it and I have questions about it....But late, now I'm too tired, time for bed.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 03, 2024, 12:03:44 am
content: It's definitely past your bedtime!

author: Martin72
author_rank: Super Contributor
timestamp: July 03, 2024, 09:38:07 pm
content: Quote from: Martin72 on July 02, 2024, 11:14:03 pmMore thanthisthread can cover...Maybe we should discuss the rest somewhere else, maybe in the ST2830 thread.But three things after all:-Why did you enter the output voltages for the ST2832 and ST42 differently, in Vrms for the ST2832 and in Vpp for the ST42?-Why did you not use frequencies below 1kHz for the inductances, at least for the larger coil values it would have been permissible.-And the third, measuring coils in the higher mH range at 100khz or more, hardly makes any practical sense.But it's nice to see that the ST42 can still keep up with the capacitors, I've noticed that too.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 03, 2024, 10:43:04 pm
content: Quote from: Martin72 on July 03, 2024, 09:38:07 pmBecause that's how each device is specified. 1V on the ST42 is 1Vpp, and on the ST2832 it's 1Vrms.Quote from: Martin72 on July 03, 2024, 09:38:07 pmMy tests followed the calibration chart that came withyourST2830. Your cal only showed testing inductance at 1kHz, so I added the others for fun. I did expand on a few areas to see what the devices could handle, but my tests covered at least what the original cal cert did, except that I changed values to simple 1, 10, 100 for each range (in resistance) rather than the other seemingly arbitrary intermediate values. If you want me to cover something else specifically, let me know and I'll add it before I do my 5th (and hopefully final) version of the test board.Quote from: Martin72 on July 03, 2024, 09:38:07 pmPractical sense or not, that falls in the 1% accuracy range at worst according to their chart. Why not push a little and see how well it works?Quote from: Martin72 on July 03, 2024, 09:38:07 pmIndeed, the ST42 did quite well across the board. I was surprised by the few failures testing at 10kHz, but I don't know what the ST42 is supposed to handle. Hopefully Shannon can release some more detailed specifications.I'm happy to discuss this further wherever you like. 😉

author: Martin72
author_rank: Super Contributor
timestamp: July 03, 2024, 11:17:13 pm
content: Hi,QuoteThis can be converted accordingly, one into the other or vice versa.Two different units make it difficult to compare them at first glance.QuoteOh, is that so?Then I'll have to have another serious word with the calibration laboratory.QuoteThis was not meant in the context of the accuracy of the LCR.QuoteIn this regard, I would exhaust the calibration possibilities of the ST42 before the measurements, if you have not already done so.Unfortunately, this is unavoidable as soon as you change the measuring frequency, even with the ST2830, if you want to know exactly.QuoteI think the idea of a test board is very good, I had already thought about it a few times, because the LC option of the DMM Check Plus is a bit too meager for me, apart from the fact that normal components were installed there, which were only measured.In this respect:QuoteIf you (or I) would start a dedicated thread via a testboard.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 04, 2024, 12:39:48 am
content: Quote from: Martin72 on July 03, 2024, 11:17:13 pmHmmm, I definitely should have corrected the voltages. I was too tired when I did that now that I think of it, and both voltages are shown in Vrms. Though the ST42 shows voltages in Vpp on it's display. Since the purpose is to see if the devices are in spec, they should be measured and displayed in the correct method for each device. I should have corrected that. I will. Thanks for pointing that out.I don't want to exhaust the cal abilities of the ST42 on my own. I would like Shannon to specify what it should be capable of at each frequency, and use the test to confirm that. I can't know if it's out of spec without specs.I would definitely like to discuss the board more before I make another version. It's pretty close, but I need some advice I think on a couple things.Thanks,Josh

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 04, 2024, 12:44:42 am
content: Here's the corrected voltages with targets added.

author: Martin72
author_rank: Super Contributor
timestamp: July 04, 2024, 12:59:03 am
content: Quote from: KungFuJosh on July 04, 2024, 12:39:48 amI'll join you soon, once this is done...

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 04, 2024, 01:07:06 am
content: Quote from: Martin72 on July 04, 2024, 12:59:03 amI'm definitely not holding my breath on that one. 😉😉

author: Martin72
author_rank: Super Contributor
timestamp: July 10, 2024, 03:18:16 pm
content: My assortment of chokes arrived today.A good opportunity to check the speed of the two LCR tweezers.The winner couldn't be clearer.Impressive.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 10, 2024, 03:54:46 pm
content: Smaller and faster, nice. 😉I'm looking forward to getting my new test board and comparing at relatively equal testing voltages this time.

author: unmaker
author_rank: Contributor
timestamp: July 10, 2024, 07:48:20 pm
content: The more I see of these tweezers, the more I want them. Still, it's disappointing to see that the price has gone up from $133 to $190 for the calibration board option. At that price I don't know if I'd consider these "cost effective" as mentioned on the Shannon website. I'm still really salty I wasn't able to get my order in using the $18 aliexpress coupon when the price was at $133.

author: tautech
author_rank: Super Contributor
timestamp: July 10, 2024, 07:59:12 pm
content: Quote from: unmaker on July 10, 2024, 07:48:20 pmJust go looking for something better.....that I very much doubt are.https://smarttweezers-store.com/

author: Martin72
author_rank: Super Contributor
timestamp: July 10, 2024, 08:04:56 pm
content: QuoteI haven't tested everything I wanted to test yet, but I can say in advance that even if it cost 190 all by itself, the price would be reasonable.

author: tautech
author_rank: Super Contributor
timestamp: July 10, 2024, 08:19:23 pm
content: Quote from: Martin72 on July 10, 2024, 08:04:56 pmWhile you might have a collection of equipment that can do all ST42 can do, nearly 2 decades ago I went to SMD smart tweezers so to not to clutter the bench with a multitude of gear that each would only provide occasional use.In all those yearsfor my needs, these useful devices have provided measurements of adequate accuracy at a fraction of the cost of a bunch of other gear and provided more mobility and convenience.Yes, I was an early adopter and remain a convert.

author: Martin72
author_rank: Super Contributor
timestamp: July 10, 2024, 08:42:08 pm
content: If you don't have any major or, better said, other requirements, the ST42 can be perfectly adequate, no question about it.The Mastech tweezers, for example, which weren't exactly the cheapest either, hardly look like the sun in comparison and I find it hard to believe that other smart tweezers for significantly more money are also significantly better than the ST42.

author: tautech
author_rank: Super Contributor
timestamp: July 10, 2024, 09:00:46 pm
content: Quote from: Martin72 on July 10, 2024, 08:42:08 pmSo do I and my experience with SMD tweezers supports this.2 decades back when I was looking for LCR test solutions ST3 was about the only solution available fromhttps://smarttweezers-store.com/and we sourced these locally and slightly discounted as there were few back then that could see the value in such a device.ST42, a much more capable device costs no more that we spent on ST3 all those years ago.Even Daves now old review of ST3 was quite unflattering of a device we had already been using for years.

author: Martin72
author_rank: Super Contributor
timestamp: July 12, 2024, 04:42:59 pm
content: Here are the results of the comparison test with 4 other LCRs.I only used one frequency because the LC option of the reference was only measured with this 10kHz.Now one important test/comparison is still missing and that is the one Shannon also uses for advertising:Measuring in Circuits....I'll do that, then I'll be done with the tweezers and then there will be a conclusion.A little tip, it won't be negative, that's for sure.Edit: Fu...forgotten to enter the 1µF values...

author: unmaker
author_rank: Contributor
timestamp: July 13, 2024, 02:22:16 pm
content: Quote from: tautech on July 10, 2024, 07:59:12 pmI was thinking more along the lines of the DE-5000. With the included tweezers I think it's a cost effective option though I would rather have the ST-42 tweezers for the smaller size.

author: unmaker
author_rank: Contributor
timestamp: July 13, 2024, 02:23:07 pm
content: Quote from: Martin72 on July 12, 2024, 04:42:59 pmThat's impressive. Would you be able to take capacitance measurements more in the pF range?

author: Martin72
author_rank: Super Contributor
timestamp: July 13, 2024, 03:18:32 pm
content: Hi,I saw earlier that I still have a 0805 SMD capacitor collection, with values from 15pF, so yes, I'll measure it later.QuoteNot so long ago I would have agreed with you, as I think the DE5000 is the best meter in its price range.However, this has changed somewhat with the testing of the ST42.I will go into this in more detail in the conclusion when I have finished my tests.

author: Martin72
author_rank: Super Contributor
timestamp: July 13, 2024, 04:12:56 pm
content: Here we go...0805 types, 5% tolerance

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 13, 2024, 05:21:24 pm
content: I won't have the V5 boards in for a few days, but I got the parts.Here's 1pF on the ST42.

author: Martin72
author_rank: Super Contributor
timestamp: July 13, 2024, 06:42:20 pm
content: Take the same capacitor and measure it in Cp mode...

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 13, 2024, 07:16:31 pm
content: Quote from: Martin72 on July 13, 2024, 06:42:20 pmOn my bench meter?

author: Martin72
author_rank: Super Contributor
timestamp: July 13, 2024, 07:17:56 pm
content: No, with the ST42 like I did..I am curious whether the value will then be lower.Edit:Cp....Cs mode seems to be "automatic" somehow, where is the user manual to be found?

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 13, 2024, 07:33:11 pm
content: I remeasured both:Rs 1.230pFRp 1.216pF

author: Martin72
author_rank: Super Contributor
timestamp: July 13, 2024, 07:47:15 pm
content: Thanks, I would have hoped for more of a difference.Regarding the display of C:Do you have a different firmware?Mine says Cp or Cs.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 13, 2024, 08:46:02 pm
content: Which fw do you have? Mine says 1.5.4.

author: Martin72
author_rank: Super Contributor
timestamp: July 13, 2024, 08:53:48 pm
content: Hi,1.5.5. from May2024

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 13, 2024, 09:11:12 pm
content: Ohh, looks like Shannon might need to update the OTA fw. I'll email him and ask about it.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 14, 2024, 01:43:04 am
content: I was curious so I threw the SMT fixture on my ST2832. Wasn't much difference between Cp/Cs there either. I didn't do more than a few minutes warmup, so take the final value with a microscopic grain of salt.

author: Martin72
author_rank: Super Contributor
timestamp: July 14, 2024, 12:38:28 pm
content: With 2V bias (according to the display)?It doesn't matter, you could now take 100kHz, because according to the data sheet values up to 1pF were tested with 1Mhz (interestingly from 1pF with 1kHz...).But this is only of academic interest, because the fact that the tolerance of the 1pF is given as 0.25pF shows how difficult it is to determine the actual value.I therefore think that both LCRs have roughly the same idea of "where" the capacitor is in terms of value (Yeah, Heisenberg).

author: mawyatt
author_rank: Super Contributor
timestamp: July 14, 2024, 01:03:28 pm
content: Quote from: KungFuJosh on July 14, 2024, 01:43:04 amWith Series and Parallel equivalents, if Rp is >> 1/W*Cp, then Cs ~ Cp, or if Rs << than 1/W*Cs, then Cp ~ Cs.BTW wrt your "Enhancement" of the original TH2830 to the ST2832, noted the DC Bias at 2V on the display. Did this come with the "Enhancement" ?? Maybe post on the TH2830 thread rather than divert this one.Best

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 14, 2024, 02:15:38 pm
content: I'll respond here since it's relevant to the discussion.Yes, the bias option came with theimprovement.But no, the 2V bias is not active in those tests. That's just showing what it's set to. There's a physical button that determines whether or not bias is active. It's a shame they didn't think to note active status on the screen.I'll hopefully remember to set that to zero for future tests to avoid confusion.ETA: I tested at 350mV and 10kHz to match the ST42.

author: mawyatt
author_rank: Super Contributor
timestamp: July 14, 2024, 02:28:34 pm
content: @ Josh,Recall you had issues with some range(s) and/or frequency(s) after the "Enhancement"?Need to go to that thread if I can find it wrt the issues.Best,

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 14, 2024, 02:42:22 pm
content: Quote from: mawyatt on July 14, 2024, 02:28:34 pmEverything was resolved eventually with some firmware updates. Which was funny. TH told ST that they already had the latest fw. So I sent ST photos of another EEVblogger's newer firmware version. That helped ST get better fw from TH, and everything has been great since then. Our antics helped ST out pretty well I'd say. 😉You can see my test attached to thispost:https://www.eevblog.com/forum/testgear/shannon-st42-lcr-tweezer-test-and-comparison-thread/msg5561319/#msg5561319The attached PDF in that post has the full results, and everything looked good. The only issue with the comparison was, as you pointed out, my test voltages weren't matched. That's why I switched the ST2832 to 350mVrms after to get closer to the 1Vpp of the ST42. Overall, matching was really good anyway except for those few spots where the testing voltage really mattered.That PDF has my version of all the cal testing that was done on Martin's ST2830.Thanks,JoshETA:Here's the LCR thread:https://www.eevblog.com/forum/testgear/th2830-vs-th2832/This thread is relevant too:https://www.eevblog.com/forum/testgear/lcr-cal-test-pcb/

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 14, 2024, 03:01:45 pm
content: Quote from: Martin72 on July 13, 2024, 08:53:48 pmI ran the OTA update again, and now I have 1.5.6. Shows Cp/Cs now. Sweeet.

author: Martin72
author_rank: Super Contributor
timestamp: July 14, 2024, 04:11:30 pm
content: QuoteWhere do you get it from?

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 14, 2024, 04:25:46 pm
content: Quote from: Martin72 on July 14, 2024, 04:11:30 pmThis page:https://shannontweezers.top/docs/upgrading-firmware/Has this link:https://github.com/shannontweezers/shannontweezers.github.io/releases/download/2023-5-10/fw-update-2023-5-10.zipDownload and run from a terminal prompt. You do updatername.exe com5 or whatever your com port is. I renamed the updater fwu.exe cause I don't like typing extra BS.To get into update mode, you leave the ST42 off, then push the joystick one direction (up or down, I forget which) then plug in the USB cable and it should enter the update mode. If it starts up and shows you charging info, it didn't work.

author: unmaker
author_rank: Contributor
timestamp: July 14, 2024, 04:47:20 pm
content: I was wondering why the latest firmware on Shannon's page is 1.5.3. Are there firmware release notes for the later firmwares?

author: Martin72
author_rank: Super Contributor
timestamp: July 14, 2024, 05:08:52 pm
content: Hi,QuoteJoystick up....Now I got 1.5.6. too.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 14, 2024, 05:09:18 pm
content: Quote from: unmaker on July 14, 2024, 04:47:20 pmHe's super slow to update anything on his website, but he does make stuff available faster with the OTA updates.One thing we know is the newer version says Cp/Cs instead of guessing. 😉

author: Martin72
author_rank: Super Contributor
timestamp: July 20, 2024, 08:49:15 pm
content: The devil is in the detail.....I thought to myself, now you're going to make something nice to rebuild, something that has hands and feet and extends the tweezers - why don't you make adapter cables with test hooks so that you can also test large components.No sooner said than done, it hardly costs anything, looks good and fits perfectly.If it weren't for one tiny little pitfall.After attaching the cables, the ST42 shows short circuits everywhere - why...Quite simply, the small screws must be screwed in insulated, because of the Kelvin functionality....Cool.Never mind, just make the holes in the blades a bit bigger - or use an original set of blades from Shannon.Either way, I think this is the more “professional” solution to extend the tweezers instead of just wrapping wire around them.I will present the final solution soon.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 20, 2024, 09:47:02 pm
content: Very nice! That is a cool idea.

author: Martin72
author_rank: Super Contributor
timestamp: July 20, 2024, 10:17:07 pm
content: Do you know where to get “spare parts”?So the blades, screws and the insulation sleeves...I googled it and ended up with Ali - but then again with the complete tweezers.

author: tautech
author_rank: Super Contributor
timestamp: July 20, 2024, 10:29:56 pm
content: Quote from: Martin72 on July 20, 2024, 10:17:07 pmDepending on which version of ST42 you ordered, you should have all these already.Remove the box foam lining and check what's underneath.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 20, 2024, 11:09:43 pm
content: Quote from: Martin72 on July 20, 2024, 10:17:07 pmYou can email Shannon directly and ask. Sometimes the Ali ad has spare tips separately also.

author: tautech
author_rank: Super Contributor
timestamp: July 20, 2024, 11:17:02 pm
content: Select: Curved Tips Only......since you were a tight bugger when you purchased them.https://www.aliexpress.com/item/1005004239869204.html

author: Martin72
author_rank: Super Contributor
timestamp: July 20, 2024, 11:53:35 pm
content: I paid just under €150, so you might expect them to have been included.But they weren't.Instead, I would now have to put down €25 for the tips only....Nice try, I'd rather drill larger ones in other tips.The subject of spare parts is a purchase decision that should not be underestimated, addressed to the gentlemen who may be thinking about distribution.In addition to the tips, the battery used comes to mind spontaneously and more importantly.Is it replaceable? Is it a freely available standard type?A potential distributor should also be able to provide information on this.So screws, insulation, tips, battery.With “You should have thought of it earlier and bought it at the same time” you won't get far in the favor of potential buyers.Just a bit of advice.

author: tautech
author_rank: Super Contributor
timestamp: July 21, 2024, 03:01:30 am
content: Quote from: Martin72 on July 20, 2024, 11:53:35 pmOf course.Instead had you selected Color:ST42 TestBrd CurvTipfrom the BUY options you would have the curved tips, screws and bushes too.The most expensive option includes the pouch also and is:ST42 TBrd LeCas Tips

author: TomKatt
author_rank: Frequent Contributor
timestamp: July 21, 2024, 12:39:39 pm
content: Whelp, now I see that plastic bead thing must be the screw insulator…. I posted earlier about opening my tweezers box in the car after retrieving it from the post and must have lost 1 of the insulators (reply #37)…. If it was in the box, it must have been loose - tiny parts like that should really have been packaged in a bag or something…Edit - I ordered the curved tips option. Anyone know where I can obtain another insulator?

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 21, 2024, 06:11:07 pm
content: Quote from: TomKatt on July 21, 2024, 12:39:39 pmEmail Shannon and ask him to include it with your new tips.

author: watchmaker
author_rank: Unknown
timestamp: July 31, 2024, 01:50:55 pm
content: Quote from: Martin72 on July 20, 2024, 08:49:15 pmBuilding on Martin's idea:Drill 1.7mm holes, thread for 1.8mm. Slit crimp lug. Leave screws installed and put test clips on when needed.Thanks Martin!

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 31, 2024, 01:57:39 pm
content: Quote from: watchmaker on July 31, 2024, 01:50:55 pmI think you need a firmware update. Current version is at least 1.5.6.

author: Martin72
author_rank: Super Contributor
timestamp: August 04, 2024, 10:23:43 pm
content: The last test is coming up, the measurements in circuits.For this purpose, the ST42 is taken to work, where there are some assembled circuit boards.The Mastech tweezers, which also boast that they can measure components in assembled circuits correctly thanks to the switchable measuring voltage, will also be part of the party.I think a "best of ten" will be sufficient.In other words, how many out of 10 components on the circuit board are reliably detected.This would be the last chance for the Mastech to shine against the Shannon.Because in all other criteria, it simply had no chance.

author: Martin72
author_rank: Super Contributor
timestamp: August 06, 2024, 07:20:36 pm
content: So, tested today.I can't show the circuit board for obvious reasons, but you can trust me.I chose an area where a lot of SMD components are "gathered", resistors and capacitors, including a large tantalum with 33µF.Resistors were tested in RDC mode, which does not allow voltage reduction, neither on the Mastech nor on the Shannon.Capacitors were tested at 0.5V and 1kHz.Of 10 resistors tested, the ST42 was able to measure 9 correctly, as was the Mastech.Of 10 capacitors tested, the ST42 could only measure 2 correctly, the Mastech only one.This is rather sobering when you consider that the measurement in circuits was emphasized as a point.However, I personally did not expect anything else.I will draw my conclusions next weekend.

author: KungFuJosh
author_rank: Super Contributor
timestamp: August 06, 2024, 07:25:59 pm
content: 2:1 is still a win. 😉Which mode did you test the capacitors in?

author: Martin72
author_rank: Super Contributor
timestamp: August 06, 2024, 07:29:47 pm
content: Cs, 1kHz, 0.5V .

author: KungFuJosh
author_rank: Super Contributor
timestamp: August 06, 2024, 09:30:29 pm
content: Was there any indication that trying Cp would help at all?

author: Martin72
author_rank: Super Contributor
timestamp: August 06, 2024, 09:53:56 pm
content: I can repeat this with Cp, the problem of measuring in circuits remains the same.For example, you have a filter capacitor at the supply voltage of the circuit and a support capacitor with a smaller value directly at a component supplied with it.And you now want to measure this capacitor, but it is in parallel with the large filter capacitor.What do you measure then, right, both.That's why I wrote that I wasn't surprised by the result.I would have been surprised if the ST42 had been able to measure a 100nF capacitor that was in parallel with a 10µF capacitor via a detour.This simply does not work in principle and is not a technical fault.However, you should then rethink your application for the device according to the realities and possibly leave it alone.That's why my overall conclusion about the ST42 will be positive.

author: KungFuJosh
author_rank: Super Contributor
timestamp: August 07, 2024, 12:06:50 am
content: That makes perfect sense. I'm still curious about whether there's any perceivable effect changing the modes while testing in circuit.Most things like that in circuit usually need to have one side lifted to be tested. It's cute when these type of devices think they can magically isolate the DUTs. Maybe someday the science will pass the magic thinking. 😉

author: thm_w
author_rank: Super Contributor
timestamp: August 07, 2024, 12:15:40 am
content: Quote from: Martin72 on August 06, 2024, 07:20:36 pmUsually when we talk about in circuit measurement for capacitors, its RC filters, series DC block caps, caps in opamp filter circuits, etc.Or for repair, decoupling caps, often we can still measure the bulk value and its overall ESR. Reading the 100nF's value alone is generally not important.Of course domain dependent as well, if its all ultra low <10pF values, then more likelyhood of the reading being wrong.

author: Martin72
author_rank: Super Contributor
timestamp: August 09, 2024, 11:16:14 pm
content: After testing it for a while, here is my preliminary conclusion on the ST42.+ Very narrow construction factor+ Very fast measuring speed, the fastest I have experienced to date.+ Still accurate, within its own tolerance+Outstanding display, nothing can beat OLED+L measurements included, many measuring tweezers only offer R and C.+Additional parameter displays+Dedicated ESR mode+DC resistance mode+open/short calibration option as with the "large" lcr meters+Excellent operation with a single element, the multi-way joystick.Virtually blind operation after a short familiarization period.+Display: right/left-handed mode+Overall a well thought-out concept+Excellent: 4-wire design up to the measuring tips+Firmware update option+Very good support, continuous updates+Excellent price/performance ratioO Design-related mechanical restriction with regard to the components to be measuredO Battery operation: Unclear situation regarding the battery used, is it replaceable, is it a regular type available everywhere?O Measuring frequency maximum 10kHz, no disadvantage, because it shows that the developer is aware that higher frequencies entail other circuit requirements that could not be met due to the design, other suppliers could take an example from this.- Housing processing in the display area- No local distributors, only available via AliexpressI was attracted to these measuring tweezers because so many people were so enthusiastic about them.I tend to be skeptical about such praise, but I was pleasantly surprised.The measuring speed is breathtakingly fast, the accuracy is good considering the design, although not outstanding, and the OLED display does an excellent job.For the money an excellent device which has now rendered my Mastech LCR measuring tweezers out of work, the ST42 is simply outstanding in comparison.Forme, however, the ST42 is not a complete replacement for all LCR measurement tasks, as the measurement voltages/frequencies/currents are too low and the tolerances in terms of accuracy are too high.But I think it would be perfectly adequate for 80...85% of all users and makes a further investment superfluous.Especially if Shannon would take up my idea regarding adapters for larger measuring objects and offer a purchasable alternative.Anyone who has been considering a DER DE-5000 should take a closer look at the ST42.My personal LCR Meter ranking:-ET35-ST2830-ET45-ST42-ET44-DE5000Summary: Good !Martin

author: KungFuJosh
author_rank: Super Contributor
timestamp: August 09, 2024, 11:58:53 pm
content: I agree with almost all of that, but there's no way I would believe the ET35 is superior to the ST2830. The nightmares you discussed alone are too much. Also, I had no trouble connecting to my ST2832 via Serial to USB adapter for SCPI and remote control.The ET35 having an ethernet port doesn't make it better, especially since it barely works. 😉ET definitelytriesto be better at support than TongHui though, I'll give them that. ET tries, but fails while TH refuses to even pretend to care. That's where ST is superior, since theyeventuallyforce TH to provide updates and such....and that's ignoring that ET put the BNCs on backwards. 😉😉😉

author: Sparrow
author_rank: Contributor
timestamp: August 10, 2024, 01:14:53 pm
content: Thank you Martin72 for your evaluation and comparison of these tweezers.For my very occasional hobbyist needs, I still think the MS8911 is adequate for ME.I do like the idea of them though.I nearly bought the Shannon but Aliexpress kept cancelling my order and I didn't have the luck the other person had of it ever going through.There appears to be a new LCR Tweezers on Aliexpress now.I'm sure that they are not in the same league but are much cheaper if that's a concern for people.It would be interesting to hear your thoughts on these:"FNIRSI LCR-ST1 Mini Smart Tweezer LCR SMD ESR Tester Resistance Capacitance Inductance Continuity Diode Test Measurement Tools"https://www.aliexpress.com/item/1005007481162384.html

author: Martin72
author_rank: Super Contributor
timestamp: August 10, 2024, 01:52:43 pm
content: @JoshI know both of them.And the software is sometimes crap for sure, but it's not the only thing that matters.We can clarify more in the appropriate thread when I'm ready for a conclusion there (will take a while).@Sparrow:I had actually considered having the Fnirsi compete against the ST42, despite the clear deficits on paper (datasheet).What I don't like about both is that they have a rechargeable battery and not an easily replaceable battery like the MS8911.I will be offering my MS8911 soon, I will keep the ST42.

author: ebastler
author_rank: Super Contributor
timestamp: August 10, 2024, 05:58:20 pm
content: Quote from: Martin72 on August 06, 2024, 07:20:36 pmThat's the main issue I have with any LCR tweezer: There are fundamental limitations to what it can measure in-circuit. So when you want to check a component in-circuit, you can never be sure (short of reverse-engineering the schematic in the relevant area) whether your results are valid or not.I liked the form factor and the thought that had gone into the design of my ST42. Then it failed, while sitting in the drawer for a few months, and while Shannon was helpful with attempts at remote diagnosis, that went nowhere. I got frustrated and put it away (my decision, not Shannon's fault) -- and after another few months, I realise that I have not missed the ST42 much at all and have happily used my multimeters instead.So for me, an LCR tweezer is clearly in the "nice to have" category, and I probably won't be getting another one soon. YMMV of course.

author: Martin72
author_rank: Super Contributor
timestamp: August 11, 2024, 04:10:27 pm
content: I made a measurement on a transformer earlier for another thread.This is remarkably close if you set a "large" measuring bridge like the ET35 to the same values as the ST42.However, it also showed why measuring tweezers are a supplement for me.Somewhat interesting:During the measurement, the ST42 had switched itself off with a battery low warning.However, it immediately displayed 60% when charging and was "full" after just 10 minutes.The capacity does not seem to be the largest, which is not surprising given the design factor.

author: ceut
author_rank: Regular Contributor
timestamp: August 11, 2024, 10:34:38 pm
content: Quote from: Martin72 on August 09, 2024, 11:16:14 pmWhen I have fixed mine (changed the CH340E), I saw the battery.As it was glued on the "wrong" side: so I have not seen what mAh and size/reference on it.But we have a superb(and unique) support from @Shannon: I don't think this is a point to noteHe gaves me some piece of the PCB drawing to help me to check voltages before finding the culpritAlso, you have done great job with checking all the LCR MeterFor me, the ST42 is number 1: I don't have the money or the space to have bigger LCR meterAlso, the tweezer format is really a great thing, only "problem" is as you say"Design-related mechanical restriction with regard to the components to be measured"And for those who are interested in FNIRSI LCR-ST1: be aware of their not-finished product with firmware bugs (example DPOX180H)

author: Martin72
author_rank: Super Contributor
timestamp: August 11, 2024, 11:02:32 pm
content: QuoteI think so.The service life of a battery is foreseeable and then what?What type is it, can you get it anywhere, can you replace it without problems...Or will it say in 3 years sorry, this battery doesn't exist (anymore), be creative or buy something new.I think the topic is definitely relevant.When the button cell in my Mastech tweezers is empty, I buy a new one from the store around the corner and that's it.It's a standard type that has been around for decades and will be around for decades.

author: ceut
author_rank: Regular Contributor
timestamp: August 12, 2024, 09:48:14 am
content: Quote from: Martin72 on August 11, 2024, 11:02:32 pmCompletely agree with you about battery powered thingsI just wanted to give my feedback about the superb Shannon support, as I was having a hardware problem.=>He helps me a lot (with PM here) to fix my ST42, with some pieces of shematics.And when I found the problem: he send me the chip, and also the back cover - all for free (because my iron solder has slipped when I tried to remove the dead chip, and I have made a little hole inside this back cover...).(if you want to check, was in previous page on the topic here:https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/msg5349764/#msg5349764)I have not find any companies doing this.The other serious one I have found is RD-Tech (PSU RD6006P and all great USB Meter I have), but they have not gave me the little capacitor to fix the overshoot fault I have found for free...(here if you want to check:https://www.eevblog.com/forum/testgear/ruideng-riden-rd6006-dc-power-supply/msg4354561/#msg4354561)So, I think we have not to be worried with @Shannon supportThat's what I have tried to explain

author: Phil1977
author_rank: Frequent Contributor
timestamp: August 12, 2024, 11:10:07 am
content: Quote from: Martin72 on August 11, 2024, 11:02:32 pmI´m quite sure that LiPo-pouches already are that ubiquitous that you will be able to buy most of the sizes in near future or slightly smaller ones with the same capacity.

author: dazz1
author_rank: Frequent Contributor
timestamp: September 13, 2024, 12:16:52 am
content: HiRob of Tautech sold me a set of Shannon ST42 smd tweezers.Up to now I have got by with a cheap Chinese component tester, but they are hopeless for smd work. I rarely use thru hole components these days and using multi-meter sized probes is harder than it should be.The ST42 is definitely not bench meter accurate, but I don't need that. It has a good display and a lot of functionality packed into a very small space.I designed and printed a 3D stand based on the Gridfinity storage system I have adopted. It can now stay on the bench where it is easily accessed while being protected.The stand holds the test board. The case and spare parts stay in the case.

author: KungFuJosh
author_rank: Super Contributor
timestamp: September 13, 2024, 12:46:37 am
content: Quote from: dazz1 on September 13, 2024, 12:16:52 amI've found it to be quite competitive even with very high-end bench meters. If you have a question about accuracy, make sure to do your open/short corrections first. Also make sure you're on the latest firmware.See attached.

author: tautech
author_rank: Super Contributor
timestamp: September 13, 2024, 12:52:17 am
content: Quote from: dazz1 on September 13, 2024, 12:16:52 amDazz, pop this message into the ST42 thread and Shannon may choose to add it to a POI list.https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/

author: KungFuJosh
author_rank: Super Contributor
timestamp: September 13, 2024, 01:16:14 am
content: That stand is pretty awesome.

author: dazz1
author_rank: Frequent Contributor
timestamp: September 13, 2024, 01:48:31 am
content: Quote from: KungFuJosh on September 13, 2024, 12:46:37 amI don't need ultra precise but your comparison shows the ST42 is more than accurate enough for my needs. Actually quite impressive performance from such a small device.

author: dazz1
author_rank: Frequent Contributor
timestamp: September 13, 2024, 01:59:26 am
content: Quote from: tautech on September 13, 2024, 12:52:17 am? ? ? POI list ? ? ?

author: tautech
author_rank: Super Contributor
timestamp: September 13, 2024, 02:09:08 am
content: Quote from: dazz1 on September 13, 2024, 01:59:26 amPoints Of Interest.We OP's/thread starters often grab links to posts and list them which provides a fast method to find them.eg. scroll down to the the POI list for the SDS804X HD we played with last Saturday:https://www.eevblog.com/forum/testgear/siglent-sds800x-hd-12-bit-dsos-coming/

author: Martin72
author_rank: Super Contributor
timestamp: September 13, 2024, 05:05:22 pm
content: Thank you Shannon !

author: dazz1
author_rank: Frequent Contributor
timestamp: September 16, 2024, 12:08:56 am
content: My Shannon tweezers refuse to beep, no matter what I say to them.I have even resorted to reading the instruction card.The sound level is 4 and ON.Hold is ON.I updated to the latest firmware.We seem to be suffering a communications breakdown, and I don't know what to do.Should I seek professional help? Maybe a relationship counseling service?

author: Sorama
author_rank: Frequent Contributor
timestamp: September 16, 2024, 04:58:11 am
content: I have the same issue.I even can’t get official confirmation if nor when the tweezers should beep.So I am going to order those Zoyi tweezers and forget about the Shannon tweezers, although they did not come cheap.

author: Kean
author_rank: Unknown
timestamp: September 16, 2024, 05:41:21 am
content: Quote from: Sorama on September 16, 2024, 04:58:11 amThis sounds rather extreme. From what I've seen and read, the Shannon tweezers are far better in terms of measurement capability. But if your needs are simple, maybe the others will suit you better. You should be able to sell your ST42 for more than the Zoyi cost.I've never considered the tweezers as something for doing continuity testing, as generally I want to compare continuity between one point and many others across the PCB - so separate probes are better.But by all means they are great for doing comparison of low ohms (short) measurements across multiple parallel components to try identify which is faulty.In terms of beeping, the only sound I've ever noticed from my ST42 is a small chirp sound. Not really a beep.You should hear the chirp (if sound enabled) on every press or movement of the joystick. For someone with hearing problems, it may not be audible.

author: Sorama
author_rank: Frequent Contributor
timestamp: September 16, 2024, 06:26:14 am
content: Mine does chirp when booting, but not when using the button.So I presume mine is a DOA.I’m aware of the quality of these tweezers, but any device you use for finding shorts (in a component) or continuity in general, should beep.Like you said, that is a main functionality of the tweezers.

author: dazz1
author_rank: Frequent Contributor
timestamp: September 16, 2024, 08:17:05 am
content: Quote from: Sorama on September 16, 2024, 06:26:14 amTo beep or not to beep wasn't a factor in my decision to buy Shannon tweezers. I never expected they could, would or should beep. It is entirely possible they are beeping, but I can't hear them.

author: Phil1977
author_rank: Frequent Contributor
timestamp: September 16, 2024, 08:52:46 am
content: Whoever uses a LCR tweezer mostly has some DMM - and continuity testing makes little sense with tweezer tips, in 99% of uses I want to test two points that need test leads.I think the Zoyi and FNIRSI LCR tweezers are that low cost that they may be the only or first instrument some beginners or students buy. So it makes sense to add this feature because it´s just a few lines of code. But I really can't see any necessity for advanced users.(Of course that´s just a personal opinion. I know there are geeks who use a HP3458 for continuity test)

author: tautech
author_rank: Super Contributor
timestamp: September 16, 2024, 08:58:21 am
content: Quote from: Phil1977 on September 16, 2024, 08:52:46 amNailed it nicely.

author: Aldo22
author_rank: Super Contributor
timestamp: September 16, 2024, 09:19:11 am
content: On the other hand, if the device can check continuity, it is not a disadvantage.Perhaps it is just enough to see whether a trace is interrupted.Changing the device for this is not exactly convenient.You don't have to talk everything down just because it's cheap.

author: tautech
author_rank: Super Contributor
timestamp: September 16, 2024, 09:24:23 am
content: Quote from: Aldo22 on September 16, 2024, 09:19:11 amChatting today with Shannon, he may be considering a new lower spec and lower priced SMD tweezer.....We need take such discussion to the parent thread:https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/

author: Sorama
author_rank: Frequent Contributor
timestamp: September 16, 2024, 10:17:07 am
content: Quote from: Aldo22 on September 16, 2024, 09:19:11 amExactly.It s simply not correct to say that any cheap instrument is bad nor is an expensive one good by default .If a beeper is built in as is the case with the Shannon tweezers than it is pretty normal that it would work and applicable when doing continuity checks.Why would it not be??

author: Sorama
author_rank: Frequent Contributor
timestamp: September 16, 2024, 10:23:26 am
content: Quote from: tautech on September 16, 2024, 08:58:21 amI have been using my Fluke 45 for finding shorts using beeper/continuity since early nineties.That bench Dmm is still going strong.When one does repairs (like I do), you often check for shorts of devices themselves like between legs of a fet, transistor, resistor and all of the smd components if applicable.So it does make (a lot of) sense to have this feature when using tweezers.It’s not always about esr…Also, Defpom tested the Zoyi and its values were spot on: are you saying that it’s not reliable because of the fact it is cheap(er) ?And that one does have a usable beeper.How hard can it be?

author: KungFuJosh
author_rank: Super Contributor
timestamp: September 16, 2024, 04:56:20 pm
content: Quote from: Sorama on September 16, 2024, 10:17:07 amVery simple: it was never advertised as a feature. The Shannon tweezers are an LCR device. I've owned a wide range of LCR's from $100 to over $10k, and not a single one of them has a continuity feature. Not one. None. That's typically a function of a DMM, not an LCR.It has been suggested to Shannon to add beeping functions for continuity and diode testing, but whether or not he implements those value added features is up to him. It's also unclear to me whether an LCR device like this would have a fast enough response time for continuity testing to make people happy anyway.Let's not pretend that it's a flaw when a seriousLCRdevice doesn't have theDMMfeature you want.Go ahead and buy more tools for the jobs you need. Nothing wrong with that. If another tweezers has a feature you want, at a cheap price, go for it! We all have drawers full of tools for different purposes.

author: Martin72
author_rank: Super Contributor
timestamp: September 16, 2024, 06:56:20 pm
content: QuoteOh yes...

author: ceut
author_rank: Regular Contributor
timestamp: September 17, 2024, 08:02:29 am
content: Don't know why the continuity is so important hereShannon has told me on PM after having asking him about this feature:" >For Resistor mode:- continuity beep with low R value you know, we need to set the beep mode when use DMM, and the low R value is not an accuracy, such as some DMM boudary is 30ohms.But ST42 could detect 30mohm resistance, how to chose a nice value as the boundary makes most people feels nice and not complicated is hard to balance."One design rule is makes life simpleadd an independent beep mode for test may be acceptable"After all, it's a precision LCR meterI have posted here all informations Shannon gave me at the beginning of this year after asking some questionshttps://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/msg5641307/#msg5641307The beep actually is only used for the auto-hold function when the Tweezer has taken a good sample (I always use this), but it is not very loud, even at level 4.Also, for any hardware problem: PM to @Shannon, he gives asuper after-sale service, and I can attest that because of my CH340E chip problem I have fixed (here:https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/msg5349764/#msg5349764)After all, we are electronicians here, so nothing (or almost) can stop usI have also tried the Uni-t UT622E: no continuity mode and I prefer the Shannon's oneAlso the Shannon is really fast to acquire sample