121GW - Is it worth it with all the problems posted on this forum? - Page 1
Forum section: electronics / testgear

author: Sparky Faraday
author_rank: Regular Contributor
timestamp: February 08, 2020, 02:04:04 am
content: Hi,I'm intrigued by the 121GW BUT I am seeing so many topics about 121GW failures and problems that I have to ask myself " Do I really need something I need to fuss with all the time to make work?".What makes it attractive is the data logging function but that seems to have endless threads about that not working, corrupted files, functions don't work, calibration gets knocked out.Does bluetooth and the related Android app work or is that fussy, too?Does any one have positive "everything works as advertised" stories about this meter?What are the odds I would get one from Amazon that works as advertised?Sparky Faraday

author: DaJMasta
author_rank: Super Contributor
timestamp: February 08, 2020, 03:13:36 am
content: Quote from: Sparky Faraday on February 08, 2020, 02:04:04 amThe vast majority of stories are that, and they are rarely documented. Such is the nature of reviews and feedback on virtually every product. This also applies to the defect rate of new units, if you knew how many had been sold through amazon vs. how many reviews were left, you'd have a much better idea of the actual defect rate, which is quite low.There are potential problems with the meter - it is not a perfect product for every application and there may still be some bugs to work out or limitations that get in the way of some features, but a number of problems have been solved with hardware and software revisions since the launch and prelaunch (there are documented issues described here that apply only to early backer pre-production units).I've had no problems with my 121GW, but I haven't dove deep into data logging or the phone app. The standard functions seem to work just fine for my purposes, and I have updated the firmware using the internal SD card and used the phone app to a limited extent. I have an earlyish kickstarter unit, but not a preproduction unit. I've used it for a couple of years. I would recommend it to others for its featureset, form factor, and value, but I know there are those around the forum who wouldn't for whatever reason.

author: NY2KW
author_rank: Regular Contributor
timestamp: February 08, 2020, 03:40:36 am
content: It's a great meter except for autoranging which is annoying slow at least for me. Maybe it can be fixed in future firmware... I've given up following the thread.

author: DaJMasta
author_rank: Super Contributor
timestamp: February 08, 2020, 04:12:52 am
content: Quote from: NY2KW on February 08, 2020, 03:40:36 amDon't know when you last checked, but a few months ago there was a significant improvement to that - still not snappy enough for some, but better than previous firmwares

author: J-R
author_rank: Super Contributor
timestamp: February 08, 2020, 04:43:47 am
content: I've used the Android and Windows apps quite a bit for short term logging and remote work and have been very happy with the results. I don't see how it could compete with some other products where you can store directly to the meter and download it later or use a physical cable for a more reliable, long-term connection. With that said, with other manufacturers you may have to pay extra for the communications and software features that the 121GW comes with out of the box.The overall speed of the meter is something to consider, perhaps 2 updates per second. Sometimes it isn't ideal. I wish you could change the resolution to obtain faster speeds.It's a bit of a Swiss Army knife. There are better products out there for specific tasks...

author: joeqsmith
author_rank: Super Contributor
timestamp: February 08, 2020, 04:45:32 am
content: I repeated Dave's speed test.https://youtu.be/-eUkSufMK5A?list=PLZSS2ajxhiQDDs_mWPLavaveGe0RGEw1M&t=455

author: Sparky Faraday
author_rank: Regular Contributor
timestamp: February 08, 2020, 07:53:57 am
content: Thanks. Since you've done some data logging maybe you can tell me :what size (GB and physical) datacard is used?, What format does it require? Where is it installed?Again, thank you.

author: e0ne199
author_rank: Regular Contributor
timestamp: February 08, 2020, 11:01:25 am
content: Quote from: Sparky Faraday on February 08, 2020, 02:04:04 amif you want to get a really good meter without problems like 121gw has, are prepared to get disappointed and has 0 patience to wait for a fix (and want to get a CAT IV multimeter rating), i advise you NOT to buy 121gw, buy a keysight, fluke or brymen instead

author: J-R
author_rank: Super Contributor
timestamp: February 08, 2020, 11:17:44 am
content: There is an included internal 8GB microSD card, formatted to FAT32. You must remove the meter from the holster, unscrew two screws and remove the battery cover to access the microSD card and copy the files to your computer. More of an enthusiast feature. I think logging to the app via Bluetooth (requires LE) is more practical. In this case the data is streamed to the app in real time. When you are done logging, you must save the data to a file. I don't think a battery powered device is realistic for long-term logging functions, especially over wireless.I would suggest better defining your requirements and how you will use the meter. "Logging" is somewhat of an abused term. Even among the big players like Fluke, Keysight, Brymen, etc. there are some serious limitations and gotchas in this area. But in many cases they could be what you are looking for instead of the 121GW.For example, the Fluke 287/289 requires an additional purchase of an external IR transceiver kit (wireless or USB + software) to download the logged data and can only graph the stored data on the device AFTER the logging session, the Fluke 3000 FC has built-in wireless but can't log internally at all and from various reviews seems to have a 10 minute logging limitation. The Fluke Connect app requires you to create an account with Fluke to use it. Keysight's Bluetooth adapter is big brick sticking out the back and retails for about $100, and the USB adapter isn't particularly special either. Keysight's software is quite good but very sneaky about hiding features behind additional purchases. Brymen doesn't even have wireless capability and their software is approaching 10 years old and for sure looks it.When I fired up the 121GW, enabled Bluetooth with no adapters needed, launched the app with no login needed and saw the live charting, it was a breath of fresh air compared to the competition. At least for the tasks I'm concerned about. Your mileage may vary....

author: rsjsouza
author_rank: Super Contributor
timestamp: February 08, 2020, 11:39:14 am
content: Since datalogging is attractive to you, compare the 121GW reviews with the Keysight datalogging features. The Keysight U127x/U128x have several trigger modes for datalogging that I find extremely attractive and could setup with ease. One example is Dave's own video "Gaussian resistors redux", where he shows the trigger setup and modes of his U1272A.As others have said, the 121GW has a slow autorange, which is comparable with the U1282A (I have this one and it is very slow to my taste). However, the Keysight has the ability to reduce resolution, which speeds up things considerably.The 121GW, however, is a packed punch: it has many features in a very compact form factor, it features Dave's low burden voltage and its SD card storage is not seen (AFAICR) in any other meter.The built-in Bluetooth was also quite unique when presented, but nowadays there are a few more options such as the Owon (B35T, B41T+), Promax PD-351, AlloSun Em3255, General Tools TS04, even the Keysight's Bluetooth adapter. They all probably have varying degrees of quality (the Keysight is nice but needs an accessory).

author: joeqsmith
author_rank: Super Contributor
timestamp: February 08, 2020, 05:18:14 pm
content: The B41T has bluetooth but I wasn't able to get it working with Windows at the time I tried it. Maybe they have improved things but there was no documentation at the time.Gossen also has a meter that support it but they want a fair amount extra for their software. On the plus side, they did document the interface so it was fairly easy to get working with LabView.UNI-T has a BLE adapter that replaced the cabled interface. They claim it supports Windows but I and other discovered there was no support for it. However, a few people had spent time reverse engineering it and with their help I was able to get it working with LabView. I like having the ability to use the cable or wireless and also that the wireless adapter uses it's own batteries.Demo showing the 121, Gossen and UT181A Bluetooth in operation. While this was a prototype 121, after having worked with one of the many revisions of the production meter, the BLE performance appears the same.

author: Muttley Snickers
author_rank: Unknown
timestamp: February 08, 2020, 11:52:48 pm
content: Quote from: rsjsouza on February 08, 2020, 11:39:14 amI'm pretty sure the Mooshimeter supports an SD card as does the Lutron 9962SD. There was also another meter which I saw recently that takes an SD card but I forget now what brand it was.https://www.lutroninstruments.eu/rlc-meters/lcr-meter-lutron-dm-9962sd/

author: rsjsouza
author_rank: Super Contributor
timestamp: February 09, 2020, 12:43:14 am
content: Quote from: Muttley Snickers on February 08, 2020, 11:52:48 pmMuttley, thanks for the clarification. The mooshimeter accepts SD card.

author: J-R
author_rank: Super Contributor
timestamp: February 09, 2020, 01:20:02 am
content: I picked up the Owon/Lilliput B35T+ a while back since I was able to get it for $20. The app permissions/reviews were alarming enough that I decided it wasn't worth keeping. I passed it along to a friend with poor eyesight since the display segments are relatively large.

author: firewalker
author_rank: Super Contributor
timestamp: February 09, 2020, 11:37:51 am
content: It is a good meter, but because of some design issues with the range switch* I always have to second guess it and fiddle with the switch when something I am measuring doesn't seem right.* It is for example pretty easy to place the rotary switch in a position that will read a small resistance even when the actual value is in the MOhm range.Alexander.

author: Sparky Faraday
author_rank: Regular Contributor
timestamp: February 09, 2020, 06:49:51 pm
content: Thanks so far for all the opinions.Now I've been looking some OWON mtrs. B41T+, OW18B, B35T+ etc. They all have data logging which works as shown in reviews, something that is sketchy with the 121, from what I've seen.Maybe the 121 is more bullet proof than the OWONS but I can buy 4 OWONS for the price of a 121 GW.I've scoured the reviews on YT and unless I try to measure a KV on the resistance function (I did that on a cheap Sears mtr years ago-poof!) it seems to be good enough.Any opinions? Or warnings?

author: Sparky Faraday
author_rank: Regular Contributor
timestamp: February 09, 2020, 10:10:18 pm
content: What problems? Did it come that way or did it get fried?Thank you.

author: Sparky Faraday
author_rank: Regular Contributor
timestamp: February 10, 2020, 06:55:02 am
content: Problem solved. I'm going with the BM235 after watching Joe Smith's review on YT. That the meter is fairly bullet proof is important. Since I'm semi retired I'm not doing as much design and mods on HIFI tube gear any more this my be the last meter I need so it will be nice if it lasts.BTW - the BM869S may be obsolete? The company is out of stock on it. Can't tell. I was looking for that, too but probably don't do enough work to justify it.If I want BT for data logging or remote reading I can pick up one of the cheaper BT meters. One on Amazon for $25.I can't thank you enough for all the info you posted, which I chased down over the last few days. I had no idea so many people are into test equipment to the degree that they need a support group to deal with an addiction.I just needed to replace my Fluke 77 which I bought when they first came out. Still works but is on shaky ground because the switch got mucked up.After all this research about meters I was caught up in worrying about features on a DMM that I may not ever need. Early onset TEA?My background:My pre-teen first voltmeters were my father's Simpson (141?) and an EICO VTVM, first scope an EICO 427 kit in the 1960s. Did TV repairs in the early '70s, vacuum tube audio design from 84-present (New York Audio Labs, Moscode, Sansui) and still do some repairs and upgrades. I have a Leader 35mhz 2 ch scope, Leader Audio osc and a distortion mtr, 2 ch ACVM and a Crown IM dist meter, a few tube checkers (one I manufactured and sold the SSTC and a Hickok TV7 I never use) and I've had them since 1984. I'm a very analogue guy. If it ain't broke down completely keep it going.It would be nice to replace all this with much smaller equipment but not necessary. Outside of an O-scope I can't find any similar items made today. I'll check the forum.Music is my first love and I hold a Masters in Jazz and perform regularly as I have most of my life, 20 years in NYC. I'm on a few records with Houston Person and Etta Jones on bass.Again thank you to everyone who helped.George Kaye

author: tautech
author_rank: Super Contributor
timestamp: February 10, 2020, 07:14:53 am
content: Fine choice Sparky, certainly not a high end DMM but one that does things like it should.My YT'er buddy Defpom uses one all the time except when he needs 6.5 digit accuracy.Me, well my Chinese Fluke 15B does everything I need.

author: J-R
author_rank: Super Contributor
timestamp: February 11, 2020, 01:51:09 am
content: The BM235 as your last meter sounds too final!I respect the BM235 in general but for the bench I've given up on it. The selector switch is stiff and the stand is tiny/flimsy/squishy.The 121GW is so much nicer for frequent daily use in my opinion.The BM869s stand is stable enough for bench use. Welectron.com is probably the best place to get one.If you're a Fluke fan, the 87V is worth having a look at.

author: Sparky Faraday
author_rank: Regular Contributor
timestamp: February 15, 2020, 12:28:27 am
content: Does your 121GW work 100% right, including data logging and BT?

author: CDaniel
author_rank: Frequent Contributor
timestamp: February 15, 2020, 07:48:24 am
content: All 121GWs have the issues discussed there ... it is not reliable especially if you are professional . Of course many beginers are happy with it ...

author: beanflying
author_rank: Super Contributor
timestamp: February 15, 2020, 07:52:17 am
content: Quote from: CDaniel on February 15, 2020, 07:48:24 amSeriously you have to be a twat here too with a thread that the OP has already resolved? You persist in slagging Dave and or the meter every chance you get. Get a new bone alreadyMine is ACCURATE and as good or better than Spec and is reliable. When turned on it just works! Not perfect and far from a beginners meter.

author: Muttley Snickers
author_rank: Unknown
timestamp: February 15, 2020, 09:16:45 am
content: Quote from: J-R on February 11, 2020, 01:51:09 amI agree that the stand on the BM235 could have been better, the other day I was repairing a circuit which involved constantly switching modes and after only a few minutes I gave up and simply pulled out another meter for voltage and left the BM235 on resistance. An addition or modification such as the one shown below should help with these concerns.https://www.thingiverse.com/thing:3666409

author: J-R
author_rank: Super Contributor
timestamp: February 15, 2020, 09:34:28 am
content: Quote from: Muttley Snickers on February 15, 2020, 09:16:45 amThat looks promising, but I think the problem still remains somewhat because the stand is mounted to the rubber holster, so when you press down it has a tendency to collapse.

author: Muttley Snickers
author_rank: Unknown
timestamp: February 15, 2020, 09:48:26 am
content: My issue was more with the selector rotation and stiffness but after closer inspection I can see that the stand does not have a sufficiently firm end stop, past that point the holster just begins to pull away from the meter which only adds to the problem.

author: beanflying
author_rank: Super Contributor
timestamp: February 15, 2020, 09:49:47 am
content: For Bench use would some sort of bucket or slightly tilted wall mount option be a good idea? I made some modded bucket a while back for my Micsig scope to change the angle and space it took up on the bench. I was going to screw the mounts down but it was fine just sitting on the bench.Biggest problem with this is the range of meters.

author: Muttley Snickers
author_rank: Unknown
timestamp: February 15, 2020, 10:05:49 am
content: A member has already done a nice stand for the 121GW.https://www.eevblog.com/forum/testgear/eevblog-121gw-bench-stand-(3d-printed)/

author: beanflying
author_rank: Super Contributor
timestamp: February 15, 2020, 10:18:45 am
content: Looks good and nice use of the probe holders on the bumper to hold it. I hadn't seen it before. I just opened up the Fusion file and tweaking the angle was only one angle to get it to 60 degrees from the 40 he had it set to.

author: J-R
author_rank: Super Contributor
timestamp: February 15, 2020, 10:29:07 am
content: Our daily DMM tasks, priorities, desires, budgets, etc. can change. So even though I liked and used the BM235 for a while after I got it, when I moved into a place where I could set up a decent workbench I suddenly had no real use for it.I picked up a calibrated 34401A and it handles most of the bench meter tasks these days.However, today I was working on a 66332A and I ended up using 4 different DMMs. They all had something useful to contribute to the project.