Shannon ST42 LCR Tweezer Test and Comparison Thread

[dazz1]

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?

[Sorama]

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.

[Kean]

So I am going to order those Zoyi tweezers and forget about the Shannon tweezers, although they did not come cheap.

This 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.

[Sorama]

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.

[dazz1]

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.

To 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.

[Phil1977]

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  )

[tautech]

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  )

Nailed it nicely. 

[Aldo22]

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. 

[tautech]

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. 

Chatting 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/

[Sorama]

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. 

Exactly.
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??

[Sorama]

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  )

Nailed it nicely. 

I 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?

[KungFuJosh]

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??

Very 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 serious LCR device doesn't have the DMM feature 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.

[Martin72]

We all have drawers full of tools for different purposes.

Oh yes...

[ceut]

Don't know why the continuity is so important here 

Shannon has told me on PM after having asking him about this feature:
"[Q] >For Resistor mode:
  - continuity beep with low R value
[A] 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 simple   add an independent beep mode for test may be acceptable"

After all, it's a precision LCR meter 

I have posted here all informations Shannon gave me at the beginning of this year after asking some questions
https://www.eevblog.com/forum/testgear/design-a-new-precision-lcr-tweezers/msg5641307/#msg5641307

The 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 a super 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 us

I have also tried the Uni-t UT622E: no continuity mode and I prefer the Shannon's one 

Also the Shannon is really fast to acquire sample