Design a New Precision LCR Tweezers with Much Lower Cost 【Shannon Tweezers ST42】

[ono]

I don't know that if this reply would stop the argument. I suggest that everyone communicate calmly, because only through calm discussions we can discover more details hidden behind ST42 and the valuable content behind them

Shannon, many thanks for your excellent answer! 1Vrms with 2.8Vpp indeed would be just a gimmick given ST42 great noise properties.

My humble suggestion is to at least put both Vpp and Vrms on your spec sheet e.g. 1/0.5/0.1Vpp == 0.353/0.177/0.035Vrms with a remark (asterisk) that ST42 AC V levels are expressed in Vpp not Vrms as many other of devices. To me it would be absolutely sufficient, and will assure potential buyers it is not a print error. 

If you want to have extremely polished product, you could also have Vpp/Vrms switch in the settings, that could switch to 0.1/0.3/0.5Vrms levels, so metrology obsessed folks can measure ST42 accuracy comparing other devices using exactly same levels. I think 0.1/0.3/0.5Vrms is most common in LCR meters.

Best, Adam.

[tautech]

No, that's not enough and late as I guess it was in USA when you typed that post it is obvious you didn't think that through.

Dunno about you but at my bench is only one USB source to charge the ST42 a PC and the instant it's connected W10 says it's not recognised albeit ST42 is not in FW mode.
Shannon needs find a failsafe solution.

Or you can spend $109 on a nice LCR Tweezers from somebody that is responsive and supportive of their product, despite that it's still in its infancy. You might need to ask somebody for help installing a driver - which should automatically install - but clearly doesn't always.
That's more a failing on Windows part than the tweezers, but obviously effects the tweezer support.

100%.

Certainly with perseverance I can crack it however the CH340 driver issue is not unique to us.
Defpom had this too with his MAC however he did have a Windows PC that had CH340 drivers already installed and I am to visit this weekend with some gear for a review/teardown  and also have him update my ST42.

I mentioned I had tried on 4 W10 PC's, one a very old i3, now a i5 build that was main workstation which died in a lockdown but now repaired  , my current i7, a much more recent build, the family i3, another old build and a very recent i3 build in the hope one of which would have existing drivers that would play nice with a CH340 device.

While Shannon does provide Windows, MAC and Linux firmware obtaining a simple and reliable USB connection to ST42 is the issue without needing to jump through hoops to have it work.

You must know we do 100's of Siglent updates and help worldwide with instrument recovery so no stranger to firmware updates at all.....some of which we have reported personally found bugs, those from members here and feature requests from members and personal feature requests and most of these get into firmware releases for us all to benefit from.

Without being able to update ST42 due to these driver issues there is no possibility I can further assist Shannon and his team with further development of his tweezers that seems to me to be a terrible shame and no doubt others are also in this predicament.

[KungFuJosh]

While Shannon does provide Windows, MAC and Linux firmware obtaining a simple and reliable USB connection to ST42 is the issue without needing to jump through hoops to have it work.

You must know we do 100's of Siglent updates and help worldwide with instrument recovery so no stranger to firmware updates at all.....some of which we have reported personally found bugs, those from members here and feature requests from members and personal feature requests and most of these get into firmware releases for us all to benefit from.

Without being able to update ST42 due to these driver issues there is no possibility I can further assist Shannon and his team with further development of his tweezers that seems to me to be a terrible shame and no doubt others are also in this predicament.

Oh, I totally get your situation. If the driver situation isn't resolved, then you'd be dealing with #s of ST42 updates also for the % of people who have an issue obtaining the correct driver. I have retail management & IT experience, I know both ends of that potential headache.

That's why I think a link to an appropriate driver should hopefully resolve that for those that auto install doesn't work for.

You could try the CH340 installer from this page (I haven't tried it): https://wch-ic.com/products/CH340.html

I would right-click the device in Device Manager and uninstall whatever wrong driver (if any) is currently installed.

I'm trying to break mine, but I can't. I have the ST42 plugged in to my PC (not in upgrade mode) and my computer detects and installs it fine. I tried to uninstall it (multiple times), including deleting the driver files. But if I scan for hardware changes, Windows 11 finds, and correctly installs it again. First it goes to unknown devices, then refreshes again, and is properly installed in com ports.

[ono]

You could try the CH340 installer from this page (I haven't tried it): https://sparks.gogo.co.nz/ch340.html

I'd strongly recommend using the latest driver from the official CH340's manufacturer WCH https://wch-ic.com/products/CH340.html or https://www.wch.cn/products/CH340.html for Chinese version. Scroll down to CH341SER.EXE

It looks the latest driver version is 3.8, while 3rd party New Zealand page provides older 3.4. Also safety-wise (malware) I'd still prefer to install driver from official large well-known Chinese manufacturer than from some small 3rd party site in New Zealand that may be dysfunctional, hacked providing infected files.

AFAIK there are countless devices on the market using WCH chips, so I really don't understand why there may be any problem with CH340 drivers in general. I personally don't use Windows. But I use official Mac driver that works absolutely fine in latest macOS https://www.wch.cn/downloads/CH34XSER_MAC_ZIP.html

The only catch is that WCH and many other sites like UNI-T are behind The Great Firewall and often are very slow or even not reachable from the outside depending on the time of the day.

[KungFuJosh]

I'd stronly recommend trying latest driver from official CH340 manufacturer site

Good point, I updated the link in my reply. And to keep things simple, the official Windows driver is attached.

[tautech]

After visiting Defpom for him to graciously update ST42 from 1.4.4 to the latest FW I can say user experience is much improved. 

Greatest single improvement is for ST42 to now display zero when no component is connected. 


Feature request for discussion and Shannon to consider implementing:
Auto LCR setting.
Capacitor autodetect measurements:
Current default display is with a Rs value which based on many years of ST3 use is more convenient to have a ESR measurement automatically displayed rather than need to select it from deep within the menu.

Please discuss.

[KungFuJosh]

Auto LCR setting.

Move the joystick left and right to change modes, there's already an Auto mode.

Capacitor autodetect measurements:
Current default display is with a Rs value which based on many years of ST3 use is more convenient to have a ESR measurement automatically displayed rather than need to select it from deep within the menu.

Pardon my ignorance, but what's the difference? Rs and ESR will show you the same value. Is there some situation that it doesn't?

[tautech]

First real use other than mucking around.....

Was gifted 2x 1.5m LED ceiling fixtures, not working.
They use a 75W rated slimline 220VDC smart driver and after after finding its datasheet became aware the driver is likely not the problem and instead the LED panels.
https://resources.tridonic.com/PDB/Ressource/GroupPdf/en/Driver_LC_75W_100%E2%80%93400mA_flexC_lp_EXC_24265.pdf

~100 3V 1W 3535 SMD LED's are in parallel pairs in each fixture and ST42 quickly identified several suspect ones that wouldn't come ON with its 3V LED test.
ST42 was perfect for this    something my old ST3 can't do.

Now to find some 3V 1W 3535 SMD LED's online......

[battlecoder]

I received mine the other day. It's certainly a fantastic product!

When testing components outside of a circuit the results are very comparable to my DE-5000. Resistance and inductance values are spot on. Capacitance readings seem always a bit lower, even after calibration, but still close enough. When testing in-circuit the ST42 is unbeatable. Setting the voltage to 0.1V provided reasonable readings for a lot of components that were impossible to read reliably with the DE-5000 (Because as far as I know, the testing voltage for that instrument is 0.5 Vrms, fixed).
I love the diode/LED tester functionality as well.

My only concern so far is the unit has "glitched" twice (see picture). I'm using firmware 1.5.3. Once it glitches, all the menus and modes glitch with the same random white lines, and the only way I've found of "fixing it" is by turning it off and on again, after which it works fine again.

[KungFuJosh]

My only concern so far is the unit has "glitched" twice (see picture).

That's not fun. I would try updating the firmware (even if it's the latest version) just to make sure a bad flash isn't the cause. Otherwise, I'd email Shannon directly if you want a faster response than waiting for a reply here.

[Shannon]

I received mine the other day. It's certainly a fantastic product!

My only concern so far is the unit has "glitched" twice (see picture). I'm using firmware 1.5.3. Once it glitches, all the menus and modes glitch with the same random white lines, and the only way I've found of "fixing it" is by turning it off and on again, after which it works fine again.

Thanks for your feedback.

Does this problem occur when the device is turned on or during use? Is there strong interference in your usage environment?

It seems that the communication of the screen is unstable. We are trying to find a way to make the root cause more obvious, or to recover after the problem occurs. We will try to implement the screen diagnostic function.

give us some time

[battlecoder]

Does this problem occur when the device is turned on or during use? Is there strong interference in your usage environment?

It seems that the communication of the screen is unstable. We are trying to find a way to make the root cause more obvious, or to recover after the problem occurs. We will try to implement the screen diagnostic function.

It has only happened during use, never immediately on power on. I don't think I have strong interference here, otherwise I would've detected that already in any of the instruments I have. I truly hope it's not a physical problem (like a bad solder or connection to the screen). If there's anything you want me to try or check let me know.

[Shannon]

I don't think I have strong interference here, otherwise I would've detected that already in any of the instruments I have.
 I truly hope it's not a physical problem (like a bad solder or connection to the screen).

Ok, if you rule out the influence of the interfering environment, it's more of a problem with the ST42 itself.

As much as we feared, hopefully it's not a hardware connection problem, if it is, and it's not easy to fix, we'll send you a new ST42 straight away.

It is being considered whether there is a way to detect this error, either during use or during factory testing. Because of its sporadic nature, human inspection is not a reliable method.

[KungFuJosh]

It is being considered whether there is a way to detect this error, either during use or during factory testing. Because of its sporadic nature, human inspection is not a reliable method.

If the cost of shipping isn't too much, it might benefit you to send a return shipping label so you can troubleshoot directly.

[battlecoder]

It is being considered whether there is a way to detect this error, either during use or during factory testing. Because of its sporadic nature, human inspection is not a reliable method.

If the cost of shipping isn't too much, it might benefit you to send a return shipping label so you can troubleshoot directly.

Today I turned it on and it gave me a low battery warning immediately, and turned itself off.

I *think* the first time it glitched was during first use, immediately after I got it. When I upgraded the firmware later that day I also charged the device, it so MAYBE the glitches are related to low battery voltage? Maybe you need to improve *when* the tweezers are giving the low battery voltage, because there's a chance that the screen becomes unstable slightly above your threshold voltage.

I am *not* certain of this, though.

EDIT: In the picture I took you can see that according to the device it still had 2 "bars" of battery left when the glitching happened. Now, I didn't use the device more than 10-15 minutes after it glitched last night, so I'm a bit surprised that today the battery was empty. That might also be a clue that it could be a low-battery detection issue, and the screen is just misbehaving when it's nearing low voltage.

I will leave the tweezers charging again, and test for a bit more over the next few days. If it glitches again I'll let you know how close to "low battery" it happened.

Regards

[xtech]

I'm curious why ST42 have the same casing as Colibri ST5C? Even UI look the same (similar layout and same fonts). Were both devices designed by the same person?

[tautech]

I'm curious why ST42 have the same casing as Colibri ST5C? Even UI look the same (similar layout and same fonts). Are the both developed by the same person?

Start reading from the start of this thread and it will become clear this is an individual development with help and suggestions from forum members.

[xtech]

I'm curious why ST42 have the same casing as Colibri ST5C? Even UI look the same (similar layout and same fonts). Are the both developed by the same person?

Start reading from the start of this thread and it will become clear this is an individual development with help and suggestions from forum members.

Even prototype in the first post looks exactly the same as my Colibri so it is hard to believe in separate individual development. I don't blame anyone but I'm curious of that situation. It would be nice if the device developer could put some light on this.

[tautech]

I'm curious why ST42 have the same casing as Colibri ST5C? Even UI look the same (similar layout and same fonts). Are the both developed by the same person?

Start reading from the start of this thread and it will become clear this is an individual development with help and suggestions from forum members.

Even prototype in the first post looks exactly the same as my Colibri so it is hard to believe in separate individual development. I don't blame anyone but I'm curious of that situation. It would be nice if the device developer could put some light on this.

But is it ?
Get out your calipers please.
Max body measurements in mm
19.5 wide
14.3 thick
63.5 long

150.5 OA.

[xtech]

But is it ?
Get out your calipers please.
Max body measurements in mm
19.5 wide
14.3 thick
63.5 long

150.5 OA.

These fits the measurements of my ST5C Colibri with 0.1mm tolerance  :-O

[dpenev]

Hi xtech,

In this thread I have seen picture of the st42 internals.
Is your device using the same cpu, etc?
Is this only the size and font which is the same?

[xtech]

It is interesting than even internal mechanical design looks similar but of course ST5C is pretty old model with much less features than ST42. But I'm pretty sure both have same origins like all other smart tweezers: https://www.smarttweezers.com https://www.ideal-tek.com

[tautech]

It is interesting than even internal mechanical design looks similar but of course ST5C is pretty old model with much less features than ST42. But I'm pretty sure both have same origins like all other smart tweezers: https://www.smarttweezers.com https://www.ideal-tek.com

Oh FFS so all bench meters and DSO's look similar too therefore share a common designer. 

This is just where a decade or 2 of development has led the industry.

FYI I've been using SMD tweezers for 15+yrs and from the same factory as your ST5 when that company was known as Bokar International and back then my ST3 wasn't even named such, instead ST-AS Smart Tweezer until the ST5 range came along.

Some spares are still available for my now old ST3:
https://smarttweezers-store.com/collections/st3-accessories

Study of this thread and the SW/FW versions clearly indicate ongoing ST42 improvements by way of FW updates and good luck finding any for the ST5 range.
Now compare pricing and it becomes clear they are similar but different products.

Clearly you have not done the study suggested and are just 

[ploxiln]

I think you're being overly defensive (on behalf of another ...) for a very reasonable question.

But I suspect a less-nefarious and more mundane answer: the mechanical components, and the screen, are available on the chinese parts market at very good prices, so it makes sense to design around them. For example, I heard some reports that the new Valve Steamdeck OLED models were made possible by the availability of the OLED screens used in the updated Nintendo Switch that came out about a year ago. The magic of mass manufacturing, and contract manufacturing in china ... if the parts are on the market at competitive prices, better to use them.

And yeah maybe the menu system was "inspired" by the most popular existing example ... kinda like how all late-90s early-2000s desktop OSes copied the windows/icons/pointer model from Apple, who copied it from the Xerox Parc Alto prototype ... it just makes sense, and there are other parts to focus on and differentiate, in this case the precision/accuracy/features/fixes.

[snorlax212]

Received mine. Successfully updated on Xubuntu 22.04. HOW-TO for linux newbees like me:
Joystick UP -> Connect
In terminal:

Code: [Select]

sudo dmesgIf you have this line among the last few..:

Code: [Select]

...
[ 1324.904988] usb 1-2: usbfs: interface 0 claimed by ch341 while 'brltty' sets config #1
...
...then execute:

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sudo apt autoremove brltty
(its common issue for ch341 with brltty, google for more info)
Again:

Code: [Select]

sudo dmesgReturn:

Code: [Select]

[ 1851.578108] usb 1-2: New USB device found, idVendor=1a86, idProduct=7523, bcdDevice= 2.64
[ 1851.578121] usb 1-2: New USB device strings: Mfr=0, Product=2, SerialNumber=0
[ 1851.578127] usb 1-2: Product: USB Serial
[ 1851.592687] ch341 1-2:1.0: ch341-uart converter detected
[ 1851.603548] usb 1-2: ch341-uart converter now attached to ttyUSB0Thus port's location is /dev/ttyUSB0
Extract firmware .zip, locate in terminal to 'fw-update-YYYY-MM-DD', execute:

Code: [Select]

sudo ./fw_update-linux /dev/ttyUSB0
You're done.