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

[Shannon]

I wonder if the shannon could do it better and if yes, why and how (didn´t read this thread so far, sorry).

Simply, Shannon never used the Mastech design to guide new product development. 

Instead focussing on what the marketplace leaders featureset and accuracy offered then bettering it.
AFAIK the only hiccup has been with a finer tip design he came up with that plainly wasn't robust enough for general purpose work.

Thanks tautech for the continued support from the very beginning 

Those tweezers that may be bent have been eliminated. Their tip thickness is 0.1~0.2mm.
At present, our tweezers have been processed more carefully, and the thickness is between 0.3~0.4mm.
I believe they are the same as your previous tweezers tips, which can be used for more than 15 years

Another news is that after many blinks, finally a batch of curved tweezers is mass-produced on a small scale, images attached

And few special true four-wire tips have been made

[dpenev]

Hi Shannon,

With your latest firmware the hold mode is not working .
It was fine with the previous version.

In my opinion the product has good potential.
Please continue to improve it but also please test more before releasing an update.
Is there a possibility for getting the previous version?

I saw you have removed the small circuit icons RC, RL, etc from the UI.
Is it to free some room on the display?

There is R and Rdc measurement modes. What is the difference?

There is SelfCalibration, Short, Open. Can you elaborate on what is doing what.

[Shannon]

Hi dpenev


With your latest firmware the hold mode is not working .
Sorry to hear that, we will test the feature and update the firmware ASAP

Is there a possibility for getting the previous version?
yes, we have preserved the recovery settings.
please try "fw_update.exe comx -v v1.5.0"

I saw you have removed the small circuit icons RC, RL, etc from the UI.
Is it to free some room on the display?
I may not understand what you mean.
RC, RL, etc are represented by circuit symbols, do you want to display it by characters?

There is R and Rdc measurement modes. What is the difference?
R is tested by AC excitation signal, Rdc is tested by DC excitation signal

There is SelfCalibration, Short, Open. Can you elaborate on what is doing what.
simplified explanation
SelfCal is used for the signal chain calibration
Short is used for removing the residual minimum contact resistance error
Open is used for removing the residual cap at open state

[dpenev]

I saw you have removed the small circuit icons RC, RL, etc from the UI.
Is it to free some room on the display?
I may not understand what you mean.
RC, RL, etc are represented by circuit symbols, do you want to display it by characters?
In the v1.5.0 in the UI there are icons like for example:
          ____
--| |--|___| --
I am just curious why you have decided to remove those icons in the latest firmware.
I guess symbols 'R', 'C' , 'L', '|Z|', etc are defining the measurement mode well enough. 

There is R and Rdc measurement modes. What is the difference?
R is tested by AC excitation signal, Rdc is tested by DC excitation signal
OK. What is the level of the DC excitation signal? I have noticed a big difference for a resistor on a PCB
measured with mode R and Rdc.
Why hold mode is not applicable for Rdc? 

SelfCal is used for the signal chain calibration
This one is not clear to me. What is signal chain calibration?
Do you suggest "short" done only before small resistors measurement?
"Open" only before small capacitor measurement?

Can you recommend an article or tutorial about using the RLC tweezers for in circuit measurement.
I guess there are recommended approaches of measuring resistors pull up, pull down, op-amp feedbacks, decoupling capacitors, etc.   

 

[Shannon]

Hi dpenev，

Thanks for your feedback, and the hold mode is working with OL feature now, we have updated the firmware to v1.5.2

I saw you have removed the small circuit icons RC, RL, etc from the UI.
Is it to free some room on the display?
when it displays OL, the mode is uncertain, so the mode is not displayed, and when ST42 detect right components, the mode display will be there.

There is R and Rdc measurement modes. What is the difference?
R is tested by AC excitation signal, Rdc is tested by DC excitation signal
OK. What is the level of the DC excitation signal? I have noticed a big difference for a resistor on a PCB
measured with mode R and Rdc.
Why hold mode is not applicable for Rdc? 
we are trying to add hold-on feature to the Rdc test.

SelfCal is used for the signal chain calibration
This one is not clear to me. What is signal chain calibration?
Do you suggest "short" done only before small resistors measurement?
"Open" only before small capacitor measurement?
well, the signal chain can be understood as a ADC.
"short" and "open" cal is not necessary for every time small and large impedance measurement.
I suggest when you found the contact resistance and open cap is not close zero as you want,
you can try to do the "short" and "open" calibration.

Can you recommend an article or tutorial about using the RLC tweezers for in circuit measurement.
I guess there are recommended approaches of measuring resistors pull up, pull down, op-amp feedbacks, decoupling capacitors, etc.   
hm...there are too many different circuits and types on the PCB, we may not have enough time to analysis them.
BUT one of the on PCB test recommendations is changing the excitation voltage to 0.1Vpp is good for most case.

[electrolust]

Debating this. The thing holding me back is the OLED screen. Not looking forward to replacing it in a few years.

[Shannon]

Debating this. The thing holding me back is the OLED screen. Not looking forward to replacing it in a few years.

Hi electrolust,

here is the screen spec, don't worry about that

[electrolust]

My own experience with Keysight U1253B OLED DMM is not good.

And see https://www.eevblog.com/forum/projects/oled-dot-matrix-display-life/

I don't trust your screen specs at all. I guess the tweezers have been around for a couple of years now. Do you still have 2021-era ones that still have a good display on them?

[thm_w]

I use these screens in a few places, yes when left on 24/7 they will dim over time.
The tweezers are probably the last thing I'd be worried about though. Its on for a few hours per week. Even if life is only 1,000 hours thats plenty.

[eliocor]

trying to update the firmware but I'm getting:

Code: [Select]

> fw_update-win.exe com27
INFO:root:Device info:
device_id :14af4eb42faffc3914af4eb42faxxxxx, conv_id:c5722982cb95a7984888707574xxxxx
INFO:root:version info:
bl_version: 0x131, brd_version: 0xb01
INFO:root:frame max data len:31760
INFO:root:app flash starts from: 10000
INFO:root:app flash size: 190.0kB
INFO:root:RAM starts from: 0x20000000
INFO:root:RAM size: 32.0kB
INFO:root:Supported feature: 0x0

INFO:root:iv is c5722982cb95a79848887075742xxxxx
 id is 14af4eb42faffc3914af4eb42faxxxxx
INFO:root:request firmware version:latest
connect to server now.
ERROR:root:Error: HTTPConnectionPool(host='43.138.101.61', port=23649): Max retries exceeded with url: / (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x000001970FE16800>, 'Connection to 43.138.101.61 timed out. (connect timeout=None)'))
No firmware got from server.

is your server down?

[electrolust]

thanks. i'm not worried about on-time. like you said, you'll never reach it. personally i'd be lucky to clock in a few hours per month.

but some displays, like the keysight DMMs, fade even when OFF. this is a known, well reported problem. i think i got 2 years out of mine (hobby use only) before replacing it. this is a known problem for the 1253 and 1273 series. the replacements you can buy are some standard OLED panel (variant of the original, which is out of production or not available in unit qty) and they die also ...

clearly not ALL OLED displays have this problem. phones and TVs last for a long time, for example. and white vs amber (keysight uses amber) could make all the difference as well.

[thm_w]

Interesting, did not know they fade when powered off. 50,000 hours is 6 years though, so at least the manufacturer thinks its ok.. Will see what others say.
Did anyone find the datasheet for that OLED from the keysight? Or was it a custom job.

[Shannon]

trying to update the firmware but I'm getting:
No firmware got from server.
is your server down?

Looks like the server is not stable, please try again later, when you encounter this problem

[Shannon]

My own experience with Keysight U1253B OLED DMM is not good.

And see https://www.eevblog.com/forum/projects/oled-dot-matrix-display-life/

I don't trust your screen specs at all. I guess the tweezers have been around for a couple of years now. Do you still have 2021-era ones that still have a good display on them?

Sure, we have some 2021-era ones, but they lie in the corner for a long time and we rarely get a chance to use them, so I can't see the difference
The good thing is this screen is easy to have

[electrolust]

thanks. i bought a set

[SilverSolder]

Is the product sold out?  I'm only seeing replacement tips in the Aliexpress store...

[tautech]

Is the product sold out?  I'm only seeing replacement tips in the Aliexpress store...

Showing some stock available for each product type here:
https://www.aliexpress.com/item/1005004239869204.html?gatewayAdapt=4itemAdapt

[Shannon]

Is the product sold out?  I'm only seeing replacement tips in the Aliexpress store...

Hey SilverSolder,

When you order the tweezers, please send us some message on the Aliexpress platform, tell us you are SilverSolder.

[TurboTom]

Anybody's been able to update their firmware during the last three days? I recently purchased a set of the Smart Tweezers and found the battery to discharge rather quickly by itself (less than one week) even if powered down, so I thought a firmware update might help. But I keep on getting the same message that @eliocor reported:

trying to update the firmware but I'm getting:

Code: [Select]

> fw_update-win.exe com27
INFO:root:Device info:
device_id :14af4eb42faffc3914af4eb42faxxxxx, conv_id:c5722982cb95a7984888707574xxxxx
INFO:root:version info:
bl_version: 0x131, brd_version: 0xb01
INFO:root:frame max data len:31760
INFO:root:app flash starts from: 10000
INFO:root:app flash size: 190.0kB
INFO:root:RAM starts from: 0x20000000
INFO:root:RAM size: 32.0kB
INFO:root:Supported feature: 0x0

INFO:root:iv is c5722982cb95a79848887075742xxxxx
 id is 14af4eb42faffc3914af4eb42faxxxxx
INFO:root:request firmware version:latest
connect to server now.
ERROR:root:Error: HTTPConnectionPool(host='43.138.101.61', port=23649): Max retries exceeded with url: / (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x000001970FE16800>, 'Connection to 43.138.101.61 timed out. (connect timeout=None)'))
No firmware got from server.

is your server down?

[Shannon]

Anybody's been able to update their firmware during the last three days? I recently purchased a set of the Smart Tweezers and found the battery to discharge rather quickly by itself (less than one week) even if powered down, so I thought a firmware update might help. But I keep on getting the same message that @eliocor reported:

trying to update the firmware but I'm getting:

is your server down?

Hi TurboTom,

We decided not to put up with the last server provider , although there were not too many problems in mainland China, it seems that it is not very friendly to international users.
Last night we moved the server address to Frankfurt, hoping to solve everyone's problems.
Please try it now.

BTW, the problem of fast battery drain, can you private message me the SN number of your tweezers?
And is it possible that the button is accidentally pressed when it is placed?

[TurboTom]

@Shannon replied to a PM and indicated a solution for the F/W update problem. Yet, in between I've been able to update my Smart Tweezers the "conventional" way. In future, utilizing their new server, this should be less troublesome I'm sure. Anyway, thanks for the support!

Regarding the mentioned battery discharge issue, I investigated the behaviour of the instrument on a daily base and finally, I'm pretty sure it was my own fault...
When not in use, I kept the tweezers in the supplied box while it also contained the folded "quick reference chart". Since the "joystick" button projects from the body of the tweezers, as long as there's only the foam padding opposite to it with the lid of the box closed, everything's fine. But if the relatively stiff paper of the quick reference chart presses against the joystick, it could very well depress it and cause the discharge problem. Investigating the chart more closely, I found traces of a depression right where the joystick would be if the chart is slided towards this edge of the box, so I assume this was actually the case.

From now on, I make sure that the chart is not covering the joystick when I close the box. No further problems observed since... 

[indman]

Del

[Shannon]

@Shannon replied to a PM and indicated a solution for the F/W update problem. Yet, in between I've been able to update my Smart Tweezers the "conventional" way. In future, utilizing their new server, this should be less troublesome I'm sure. Anyway, thanks for the support!

Regarding the mentioned battery discharge issue, I investigated the behaviour of the instrument on a daily base and finally, I'm pretty sure it was my own fault...
When not in use, I kept the tweezers in the supplied box while it also contained the folded "quick reference chart". Since the "joystick" button projects from the body of the tweezers, as long as there's only the foam padding opposite to it with the lid of the box closed, everything's fine. But if the relatively stiff paper of the quick reference chart presses against the joystick, it could very well depress it and cause the discharge problem. Investigating the chart more closely, I found traces of a depression right where the joystick would be if the chart is slided towards this edge of the box, so I assume this was actually the case.

From now on, I make sure that the chart is not covering the joystick when I close the box. No further problems observed since... 

Thanks a lot for your information.

We used to put the "quick reference chart" in the box,
As you mentioned, one of the issues is the Joystick may be pressed when the box is closed,
and the other issue is the box is easy to open accidentally.

For the Fw update, we will move the server from China Main Land to the EUR,
one of the following action is the fw_update program need to be updated.
When we release the new fw_update program, I will inform you all in this thread

[Shannon]

One of the good news is, the new EPR police for EEE in Germany will be executed on July 1, 2023. Environmental protection makes relevant laws and policies more and more perfect.

Suppose German friends follow the early users of Shannon Tweezers. In that case, you may have experienced a situation where you could not find ST42 on Aliexpress, because we got rid of applying for EPR qualification at that time, and then we spent some money to apply for the EPR license last year.

This time we may not be able to afford the new German EPR EEE policy, the cost is about 550 USD.
So friends in Germany, if you are interested in ST42, it is best to place an order before the new policy is implemented.

PS: We are still consulting relevant policies and trying other application methods to solve this problem. For example, our application does not focus on store, but only applies for a certain brand or a certain product.

[Shannon]

A new firmware update program and a new server address have been released! 

here is the new program download link: https://github.com/shannontweezers/shannontweezers.github.io/releases/download/2023-5-10/fw-update-2023-5-10.zip