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Products => Test Equipment => Topic started by: bffargo on March 06, 2026, 04:42:56 am

Title: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: bffargo on March 06, 2026, 04:42:56 am
Oh yes they did it.  Starting to look like Fnirsi with the flood of devices.  This one isn't cheap either. Doubt it would be any better than the original  ATMega328 based units with the highly tweaked and supported open source firmware.

https://www.aliexpress.com/item/3256811577169825.html (https://www.aliexpress.com/item/3256811577169825.html)
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: Aldo22 on March 06, 2026, 09:55:51 am
I think it's primarily a rechargeable 25,000 counts DMM with IPS Screen a few extras like the "waveform" graph.
That explains the price, in my opinion.
You get the transistor tester on top of that.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: @ on March 07, 2026, 02:35:33 pm
Looks interesting...

Listing for $42.57: https://aliexpress.com/item/1005011769799035.html Whoops, looks like I got the last one ... that one's now $72.

Specs pros and cons at first glance:
:-- no 250μA or 2.5mA range as on other Zoyi models, despite having two jacks.
:-- frequency measurement tops out at 1MHz
:-+ 250Mohm range (accuracy is 5%, though)
:-+ 100mF capacity range

With the firmware being upgradeable, this could be a nice unit for some tinkering. One of the screenshots shows different versions for the "Main" and "Tester" firmware, so I'm wondering if there's actually an ATmega328 (or clone) in there (which would be the "Tester"). The multimeter part looks similar to what they have in the ZT-XR1 battery tester or ZT-R01/R02 infrared cameras.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: indman on March 07, 2026, 04:36:29 pm
With the firmware being upgradeable, this could be a nice unit for some tinkering. One of the screenshots shows different versions for the "Main" and "Tester" firmware, so I'm wondering if there's actually an ATmega328 (or clone) in there (which would be the "Tester")
Forget about ATmega328 in these combined devices. The basis of the transistor tester will be a Chinese STM clone with firmware without the ability to radically configure or change anything. ;)
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: Aldo22 on March 09, 2026, 09:42:17 am
The multimeter part looks similar to what they have in the ZT-XR1 battery tester or ZT-R01/R02 infrared cameras.

In terms of basic data (counts, basic accuracy), yes, but in detail they are all different.
The ZT-XR1 has no current measurement at all, and although the ZT-R01/R02 have a 25mV range (which the ZT-XT1 does not have), they do not have a 250μA or 2.5mA range either.
In terms of measurement capabilities, none of them completely replace the ZT-225.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: lsqm01 on March 19, 2026, 03:04:08 am
 :)Hey everyone, I'm an electronics enthusiast from China and I finally came across this review thread for the ZOYI ZT-XT1. I've been debating whether to get it as my first multimeter—how's its overall performance? Really appreciate your thoughts and input! :)
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: Aldo22 on March 19, 2026, 10:45:43 am
:)Hey everyone, I'm an electronics enthusiast from China and I finally came across this review thread for the ZOYI ZT-XT1. I've been debating whether to get it as my first multimeter—how's its overall performance? Really appreciate your thoughts and input! :)

I don't know, I think it's too expensive for what it is.
I'd rather buy a ZT-225 and a TC1, unless you really want the IPS screen on the DMM.

For example:
https://www.aliexpress.com/item/1005011825939113.html (https://www.aliexpress.com/item/1005011825939113.html)
https://www.aliexpress.com/item/1005004063983355.html (https://www.aliexpress.com/item/1005004063983355.html)
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: lsqm01 on March 19, 2026, 10:52:21 am
Thanks for your reply! Yeah, even here in China, this meter goes for around $39. What really caught my eye is the transistor tester feature, though it seems like it's based on the open-source LCR-T4 project. But at this price, it just doesn't feel quite right. Appreciate your input! ;)
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: @ on March 19, 2026, 07:34:01 pm
I was able to get one for just under USD 40. I would agree that $65 or $70 is too much.

Both meter and component tester work ok, though I don't have any precision references to check against. The operation using rubber buttons is not very ergonomic, I much prefer a rotary switch. On top of that, the missing low current ranges don't make this usable as a primary meter even for a low budget, in my view. That of course depends on whether one tends to to mainly low power electronics. The ZT-303 or ZT-225 are much better as multimeters, but of course without the component tester functionality.

The multimeter functionality is done by an Artery AT32F403A Cortex-M4 talking to a DM1109CEN multimeter ASIC. The MCU's flash memory seems to have read-out protection enabled.

The component tester is a Nation/Nsing N32G031, so a cheap Cortex-M0, as @indman suspected. I was able to read the flash memory and may try to analyse it.

You can see the 680R and 470k resistors commonly used in the component testers.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: indman on March 19, 2026, 07:41:24 pm
Both meter and component tester work ok, though I don't have any precision references to check against.
Thank you for the high-quality photographs of the internal world of this device. Show us, if it’s not difficult, photos the capacitors measuring , for example MLCC with a capacity of 1-10 μF?
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: @ on March 28, 2026, 09:12:00 pm
Measuring capacitors in multimeter mode works similar in speed and accuracy to other cheap DMMs. Sorry, I don't have pictures at the moment but they wouldn't be very interesting I think.

As for the component tester, I was taking the unlocked Cortex-M0 chip (N32G031) as an opportunity to learn to use Ghidra (https://github.com/NationalSecurityAgency/ghidra) for reverse-engineering. The ADC measurements are converted to float numbers. Then it's mostly basic arithmetic, but in very inefficient soft-float implementation: multiply by 5 (volts), divide by 4095 (not 4096?) to get a voltage value. This could have been done more efficiently with integer math on the Cortex-M0, or by transferring the raw ADC value to the Artery M4 chip, which has a hardware FPU.

The two MCUs communicate over bog-standard 115200 baud UART, by the way. The N32G031 firmware doesn't implement any low-power/sleep functionality, I believe the master Artery MCU simply powers off the 5V boost converter to it unless there is a component measurement requested by the user (by pressing the TEST MODE button).

The firmware is also built with low optimization level and asserts enabled, which at least helps with reverse-engineering. There also is a bit-banged logging output on PF1 (pin 3) which uses printf, with all that entails...

I think I found a bug with the ESR measurements of capacitors. The measurement is done 10 times, with the first 9 results inexplicably being thrown away. Just the ESR measurement thus takes over 6 seconds instead of under a second. I also very much doubt the accuracy of the ESR measurement: The results are repeatable, but adding discrete resistors <10R in series doesn't change the result anywhere near like it should. I don't have another ESR meter to verify the ZT-XT1's result.

At the moment I don't have a way to attack the main processor, and that's the one that handles the entire user interface. So there isn't a way to extend the functionality of the component tester. I'm hoping for Zotec to release a firmware update, so I could analyse the Artery chip's firmware image.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: indman on March 29, 2026, 06:30:19 am
Measuring capacitors in multimeter mode works similar in speed and accuracy to other cheap DMMs. Sorry, I don't have pictures at the moment but they wouldn't be very interesting I think.
I'm not interested in DMM in this device. I asked you to take photos of capacitance and ESR measurements in component tester mode.

I think I found a bug with the ESR measurements of capacitors.
So far, our Chinese friends have not been able to correctly transfer the code from the author’s project to the new architecture. Therefore, there will be errors not only when measuring ESR. ;)
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: TheDefpom on March 30, 2026, 08:46:28 am
Zoyi sent me one to review, I haven't got that done yet as I have been flat out with other things, but I should get it done in the next week.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: BillyO on April 07, 2026, 02:36:26 pm
https://www.youtube.com/watch?v=OnnzWIYerAY (https://www.youtube.com/watch?v=OnnzWIYerAY)
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: @ on April 07, 2026, 07:38:01 pm
Thanks for making a video on this device, Scott.

Your unit seems to be missing the plastic frames for the plug-in boards, too. A post on a chinese forum shows these, see below. I think the boards would be less wobbly with these in place.

I poked around the firmware for the component tester and here are some things I found:
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: MrCreosote on April 07, 2026, 07:49:44 pm
I'd consider the Zoyi, but all I really need is a "T7" - and it looks like any variant will do what I want.  So that leaves Cheapest one on Aliexpress vs Cheapest one on Amazon.

However, if the Zoyi added oscilloscope functionality, it would have everything I need in my hand and I'd probably buy it. 
(Wouldn't be surprised if such a tester shows up within 6 months.

Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: bffargo on April 07, 2026, 07:49:52 pm
As the one that first spotted this and started this thread calling out Zoyi as turning into another Fnirsi with the flood of similar and odd franken-tester things, I didn't think I'd end up buying one of these, especially before the hardware hacking experts got to it. But a random login to the AliExpress app last night presented me with not only a special offer price discount but also a huge 40% off with Coins deal + $7 off 49 all stores coupon, bringing it down well below the ~$42 price level I had seen it hit during the anniversary sale last month.

So for $24.50 + tax, I ended up succumbing to the curiosity. Though still not expecting much out of it other than to finally get a graphing DMM I guess. Will eagerly watch if anyone figures out its secrets on the xtor side.

As far as the plastic shells around the modules; are you sure those weren't just 3D prints by the user vs. something official from ZOYI?
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: oskimac on April 08, 2026, 03:59:04 am
I just came across Defpom's review video. I think Zoyi really missed the point here. To me, it’s just a component tester without anything new, plus a poor DMM attached. They had a lot of opportunities to improve the concept, but they failed.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: indman on April 08, 2026, 05:37:34 am
I just came across Defpom's review video. I think Zoyi really missed the point here. To me, it’s just a component tester without anything new, plus a poor DMM attached.
In my opinion, the multimeter in this device is of good quality and can be used. But the component tester raises more questions than answers about the need to use it in the future practice of an amateur radio operator?
I did not see in the video review above a detailed analysis of all the capabilities of the component tester, testing only a few copies of transistors is not a serious test.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: bffargo on April 17, 2026, 11:10:40 pm
Mine arrived today (the ~$24+tax special deal). Main 1.0.8 MM / Tester 1.1.3 firmware like everyone else's.  The 2 adaptor boards came with a black plastic shell around them, not just the bare PCB. Mine came with an extra ZOYI logo'd semi hard shell case (not just the nylon bag inside the box) which smelled like awful burned plastic but was in normal shape.

The limited button toggling modes is annoying as are the orders of up and down/left and right accordingly. Haven't put it through its paces much. The continuity mode at least is very sensitive and latched.  In all modes it seems there is a delay between the first meter readout vs. when the graph starts updating.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: coromonadalix on April 18, 2026, 03:58:10 am
its a mix of many things, while each section is not the very best,   it is not a full fledged multimeter   etc ...

Do not buy this thinking you're all set, same for Fnirsi  etc ...   all compromise, not fully safe and CATxx  compliant
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: SammysHP on May 08, 2026, 09:37:07 pm
New firmware "110 116" available:

http://www.szzotek.com/h-col-159.html (http://www.szzotek.com/h-col-159.html)

Quote
The new XT1 update includes the following:
1. Improved measurement error after 100mH inductance measurement.
2. Improved inductance and resistance identification and display.
3. Added JFET identification, such as 2N5457.
4. Added detection for some IGBTs, such as 25N120.
5. Improved multimeter hold display.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: uncle_sem on May 15, 2026, 07:21:53 am
with this new firmware transistortester says "resistor" without value when nothing is connected, and capacitor with some pF when socket is inserted....  |O
where can I download older firmwares?  :-//
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: Aldo22 on May 15, 2026, 08:41:33 am
with this new firmware transistortester says "resistor" without value when nothing is connected, and capacitor with some pF when socket is inserted....  |O
where can I download older firmwares?  :-//
Have you performed a calibration after the FW update?
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: SammysHP on May 15, 2026, 12:01:16 pm
with this new firmware transistortester says "resistor" without value when nothing is connected, and capacitor with some pF when socket is inserted....  |O
where can I download older firmwares?  :-//
Sorry to hear that. Mine came with 1.0.8-1.1.3 and it shows the same behavior.

Other firmware is unfortunately not available for download.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: uncle_sem on May 15, 2026, 12:33:34 pm
Have you performed a calibration after the FW update?
hmmmm.... interesting idea, I'll try it later...
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: kae64 on May 15, 2026, 03:54:50 pm
The service sent me the firmware - XT1_ZOYI_108_113, but my transistor tester doesn't initialize; it shows version 0,0,0. On XT1_ZOYI_110_116, everything seems to work except for the automatic DC voltage measurement mode.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: kae64 on May 16, 2026, 08:01:51 pm
Of the downloaded firmware, could you tell me if the XT1_ZOYI_108_113 firmware was fully installed? My multimeter installs version 1.0.8, but the transistor tester doesn't, showing version 0.0.0. The XT1_ZOYI_110_116 firmware is fully installed, but the DC voltage auto measurement mode behaves oddly: up to 10 volts, it shows erroneous values, but above that, it measures correctly. When changing registers, it measures correctly.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: jebem on May 19, 2026, 04:36:35 pm
Did someone checked the video below?
Apparently the ZT-XT1 is not able to identify high power transistors like the PNP 2SA1302 or the NPN 2SC3281 identifying them as a pair of diodes.
The reviewer then used his trusted atlas DCA55 to confirm that the transistors are in good shape.

Most probably the ZT-XT1 needs to be further tested at the factory and bugs corrected.
The reviewer conjecture was that the ZT-XT1 is using very low test current when compared to the atlas  DCA55, and that combined with larger transistor internal capacitance may not be able to provide correct bias.

https://www.youtube.com/watch?v=IPhyPQCYO9U (https://www.youtube.com/watch?v=IPhyPQCYO9U)

Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: jebem on May 21, 2026, 03:08:50 pm
It was very hard for me to find a picture of the front side of the PCB assembly.
Checked one of the popular Chinese tech sites and found one.
I am attaching it here, I hope our Chinese friends will not mind.

Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: coromonadalix on May 21, 2026, 05:05:42 pm
el cheapo transistors and component testers will do a better job,   and they have better support  loll
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: @ on May 21, 2026, 06:26:30 pm
I have started a project for an alternative, open-source firmware. It's hosted on Github: https://github.com/sw/zt-xt1-dmm (https://github.com/sw/zt-xt1-dmm)
[attach=1]

At the moment it doesn't really offer an advantage over the official firmware, but hopefully that can change.

I have attached the binary if you want to try the current state. [attach=2] You can always flash Zotek's firmware from http://www.szzotek.com/h-col-159.html (http://www.szzotek.com/h-col-159.html) later. But you use this at your own risk.

Note that with their latest release (XT1_ZOYI_110_116.bin), Zotek have activated the flash protection on the N32G031 (component tester) MCU. That means that every time you upgrade *their* firmware, you ideally have to do a calibration of the component tester, because the calibration values get erased - don't blame that on me! It's unfortunate and silly that they have done that, as they're still publishing the firmware images in unencrypted form. It should however still work without the calibration procedure, it'll just use the default values.

My firmware is mostly working ok for the DMM part. That was actually not too difficult because the (proprietary?) DM1109CEN chip does most of the work. It outputs the measurement as 7-segment digit data over UART. I haven't found any obvious way to get more out of it, for example higher update rate or different ranges.

As for the component tester part, this is quite tricky as the ADC in the N32G031doesn't seem that well-behaved. It's rather poorly specified, there's an erratum, but even taking that into account, it takes a bit of fiddling with delays and sampling time.

So at the moment this is more of a learning project for me than anything useful for the world, but I'm publishing it nonetheless.

I used this as an opportunity to learn:

The documentation is a bit sparse at the moment, I hope to improve on that. Also note that the source code is structured based on the reverse-engineering of the original firmware, so it's not the most elegant.

I probably will try to fix the broken hFE measurement for Darlingtons next.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: @ on May 21, 2026, 07:16:48 pm
Had a look at the mentioned power BJTs. While I don't have the devices at hand, I can run the spice model. It seems that these fail the measurement of the base-emitter voltage which is expected to be between 0.5V and 0.9V. Both the NPN and PNP are around 0.45V, because the collector current is so low (~1mA). So these are not classified as BJTs, but later in the procedure the two diode junctions are detected.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: kae64 on May 22, 2026, 04:40:57 pm
I have started a project for an alternative, open-source firmware. It's hosted on Github: https://github.com/sw/zt-xt1-dmm (https://github.com/sw/zt-xt1-dmm)
(Attachment Link)

At the moment it doesn't really offer an advantage over the official firmware, but hopefully that can change.

Thank you very much.
Your firmware helped me fix a glitch: the firmware component responsible for the component tester wouldn't install. Also, your firmware doesn't have an option to access the settings menu, so maybe that's just the issue with my glitchy unit.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: SammysHP on May 22, 2026, 06:49:42 pm
Thanks a lot for your work on trying to reverse engineer and improve the firmware! @ajar171 did something similar with the ZT-703 (until he disappeared from the forum), although his version was developed completely from the ground. I think Zoyi makes simple and relatively inexpensive, yet still capable hardware and just needs a little help with their firmware. Too bad they don't open-source it.

Anyway, I'm in contact with Zoyi regularly, and because Zoyi isn't actively monitoring this forum, I offered to collect bugs, complaints and feature requests for them. In addition to things already mentioned here, do you have any additional feedback?

PS: I won't tell them about the reverse engineering as I fear they might lock it down and required signed builds.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: @ on May 23, 2026, 01:33:16 pm
Also, your firmware doesn't have an option to access the settings menu, so maybe that's just the issue with my glitchy unit.
I haven't implemented the settings menu, as I didn't see a need for it, personally. The calibration procedure for the component tester is also missing, I might do that some time.

In addition to things already mentioned here, do you have any additional feedback?
Nothing else has come up so far. But with the already discovered bugs and the so-so performance as a multimeter (missing low current ranges), I wouldn't really recommend people buying it. Better get a ZT303 and an ATmega-based component tester.

Anyway, I had a go at improving Darlington measurements and also relax the checks for power BJTs. The latest version is on Github and attached as a binary.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: jebem on May 25, 2026, 05:12:49 pm
Just received my ZT-XT1. Had a drief test of the component tester part.

While it can identify some power TRIACs that my old trusty "Multi-function Tester - TC1" can't, the new ZT-XT1 fails to identify some of the small P-FET and N-FET transistors I have in stock,  namely the 2SJ176 and the BF245, seeing them as resistors.

Well, let us hope the manufacturer is reading this forum and take advantage of our free testing service to debug the firmware.

Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: @ on May 26, 2026, 07:07:12 pm
Zotek seem to have broken the JFET detection in version 110_116. Unfortunately a direct downgrade to from 110_116 to 108_113 is not possible.

If you're feeling adventurous, I've attached the latest version of my alternative firmware [attachurl=1]. That has the old JFET detection logic. That is also not perfect, but I need to read up on JFET theory before I can try to improve it. I don't really have any experience with them. Just using a J109 for testing, which gets identified correctly.

Once you install my firmware, it would then be possible to install 108_113, which I've also attached. [attachurl=2]
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: jebem on May 30, 2026, 05:37:14 pm
Zotek seem to have broken the JFET detection in version 110_116. Unfortunately a direct downgrade to from 110_116 to 108_113 is not possible.

If you're feeling adventurous, I've attached the latest version of my alternative firmware (Attachment Link) . That has the old JFET detection logic. That is also not perfect, but I need to read up on JFET theory before I can try to improve it. I don't really have any experience with them. Just using a J109 for testing, which gets identified correctly.

Once you install my firmware, it would then be possible to install 108_113, which I've also attached. (Attachment Link)

Thank you for your work.
I may try your firmware as soon as I have the chance.

Concerning the jfet identification issues, the J109 and the BF245 are very different N-JFET devices.

They have different pinout on the same TO-92 package.

While the J109 is a switching device with 85pF high capacitance, 40mA high current, 12ohm low RDS(on), 1MHz cutoff, 16mSiemens high transconductance, Vgs(off) of -2V to -6V;

The BF245 is a RF device with 3pF low capacitance, 6.5mA low current, 500ohm high RDS(on), 700MHz cutoff, 6mS transconductance, Vgs(off) of -0.5V to -8V.

Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: SammysHP on May 30, 2026, 05:40:47 pm
FYI: I forwarded a summary of all the issues we identified here to Zoyi. Let's see if they are at least trying to improve it.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: jebem on May 30, 2026, 06:05:56 pm
When doing repairs, I always use a DMM for semiconductors or a LCR for passive components to check them.
That is my first choice, not a Component Tester.

A Component Tester is handy to have additional information on semiconductors, like pinout and device type, specially when the markings are obscured or are SMD coded.

Data sheets are absolutely essential, but sometimes it is very hard to find a datasheet for the markings we see on the component.

Additionally, many datasheets are incomplete, showing just static parms and no dynamic graphs.

Even when the datasheet is comprehensive, that does not tell where the component we are checking is behaving in that way.
Neither the Component Tester.

Unfortunately these Component Testers do not test the semiconductors using the proper static and dynamic bias settings.
How could they?
They identify the component type (if we are lucky), but they use a limited set of bias settings per type, not the real life adequate bias specific per semiconductor reference.

So, a Curve Tracer is the way to go if we need to see the real behaviour of the component.

Bottom line, I like the XT1 2 in 1 approach, as I need a DMM and then a component tester when doing repairs.
Having to use two separate equipments on the workbench when I can do the job with just one, I opt for the XT1.




Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: jebem on May 31, 2026, 01:12:05 pm
FYI: I forwarded a summary of all the issues we identified here to Zoyi. Let's see if they are at least trying to improve it.

Thank you very much for your work on this subject.

I have contacted ZOYI support by mail reporting my two issues found with the 2SJ176 and BF245 JFET components that my TC1 can easily correctly identify.

Also I asked them for a firmware update and where exactly could I download it.
Their response was that all equipment leave factory with the latest version, not clarifying what was that latest version. But they provided the exact IP address to their repository.

Now, the strange thing here is that my unit came with version "Main:1.0.8 Tester:1.1.3", but for some strange reason, on their repository this version is not available.
Instead they offer another more recent version "XT1 Firmware Version 110-116" that have some fixes including some type of JFET components like the 2N5457.

From the experience from others members we know that the above 110-116 is even worse than the shipped factory version "Main:1.0.8 Tester:1.1.3".
So, I asked ZOYI support once again for clarification and got no answer so far.




Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: SammysHP on May 31, 2026, 02:13:36 pm
Version 108-113 was shared earlier here in the thread:

https://www.eevblog.com/forum/testgear/ziyi-zt-xt1-dual-transistor-tester-multimeter/msg6270760/#msg6270760 (https://www.eevblog.com/forum/testgear/ziyi-zt-xt1-dual-transistor-tester-multimeter/msg6270760/#msg6270760)
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: jebem on May 31, 2026, 03:47:41 pm
Here we go for another random testing on small TO-92 or alike encapsulated semiconductors.

Equipment under test:
E0: "ZOYI ZT-XT1" Firmware M:1.0.8 T:1.1.3

Equipment for comparison:
E1: "FNIRSI LCR-P1" and
E2: "Multi-function Tester - TC1"

Identification errors in this test:

1. BS208 - P-channel enhancement mode vertical D-MOS transistor, https://bg-electronics.de/datenblaetter/Transistoren/BS208.pdf (https://bg-electronics.de/datenblaetter/Transistoren/BS208.pdf)
E0 see a Transistor(NPN).
E1 and E2 agrees.
(My DIY curve tracer also agrees)

2. 2N5457 - General Purpose N−Channel − Depletion JFET, https://www.onsemi.com/pdf/datasheet/2n5457-d.pdf (https://www.onsemi.com/pdf/datasheet/2n5457-d.pdf)
E0 see a Resistor.
E1 and E2 see a N-JFET but D/S pinout is incorrect on E2.

3. BF245 - JFET VHF/UHF Amplifiers N–Channel — Depletion, https://www.onsemi.com/download/data-sheet/pdf/bf245a-d.pdf (https://www.onsemi.com/download/data-sheet/pdf/bf245a-d.pdf) (previouly reported here)
E0 see a Resistor.
E1 and E2 see a N-JFET but D/S pinout is incorrect on both.

4. J176 - P-channel silicon symmetrical field-effect transistor (Drain and source are interchangeable), https://www.nxp.com/docs/en/data-sheet/J174_175_176_177_CNV.pdf (https://www.nxp.com/docs/en/data-sheet/J174_175_176_177_CNV.pdf)
E0 see a Resistor.
E1 and E2 see a P-JFET but E1 gets confused on D/S and assigns pin 1 to both.



But not is all bad in this XT1.
It can identify most of my transistors, and not only the plain NPN/PNP bjt ones. For instance:

5. 2N5064 Thyristor
E0: Perfect identification.
E1: See a NPN with hfe 636
E2: See a NPN with hfe 16

6. SK152 - N-Channel JFET (S/D pins are interchangeable)
E0, E1, E2: Perfect identification, but E0 S/D assignment differ from E1 and E2.

7. BS170 - Field Effect Transistor N-Channel, Enhancement Mode
E0, E1, E2: Perfect identification as a MOSFET(N-MOS)

8. MPF102 - JFET VHF Amplifier N−Channel − Depletion
E0, E1, E2: Perfect identification.


Just an observation:

I'm starting to see a pattern here. The components that are failing identification, show their transfer curves with very low current on my DIY curve tracer, meaning the curves appear overlapped at the bottom side of the graph, as the curve tracer is programmed for 0 to 50mA in the vertical axis. I would need to modify the programm to use a scale of 0 to 5mA to be able to see the curves.

Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: indman on May 31, 2026, 03:57:08 pm
Here we go for another random testing on small TO-92 or alike encapsulated semiconductors.
You need to have at least one tester with an original author's firmware instead of a Chinese one in order to correctly assess the capabilities of these toys in a beautiful case.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: uncle_sem on June 04, 2026, 04:57:38 am
original authors firmware also had a bugs, most of them was fixed by community, and I think author do not supporting this device anymore
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: indman on June 04, 2026, 05:11:10 am
original authors firmware also had a bugs, most of them was fixed by community, and I think author do not supporting this device anymore
You are mistaken, one of the authors madires and today supports his version of m-firmware. The other author k-firmware is not so active lately, but his firmware version is still relevant today and does not contain such stupid and childish errors as the Chinese one. :)
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: liutas on June 04, 2026, 05:32:07 am
And where can I find their software?
Thanks
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: indman on June 04, 2026, 05:34:29 am
liutas
https://github.com/madires/Transistortester-Warehouse
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: liutas on June 05, 2026, 05:45:17 am
liutas
https://github.com/madires/Transistortester-Warehouse

When I opened your link, I didn't find anything related to this topic. „Zoyi ZT-XT1
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: indman on June 05, 2026, 05:50:15 am
When I opened your link, I didn't find anything related to this topic. „Zoyi ZT-XT1
This is a link to the author's firmware, which should be used as a sample for comparing test results.
I thought you were asking about this?
Of course, there are no Chinese firmware options for the Zoyi ZT-XT1, so look for them on the ZOTEK website
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: jebem on June 05, 2026, 06:04:43 pm
liutas
https://github.com/madires/Transistortester-Warehouse (https://github.com/madires/Transistortester-Warehouse)

When I opened your link, I didn't find anything related to this topic. „Zoyi ZT-XT1

Indam was referring to the original author of the component tester.

Zoyi have s support webpage at:
http://44.250.232.244/?support/ (http://44.250.232.244/?support/)

All available firmware for the different equipment is there.
Please read all posts from the beginning to learn about the issues found by members.

Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: Skander on June 05, 2026, 09:10:04 pm
liutas
https://github.com/madires/Transistortester-Warehouse (https://github.com/madires/Transistortester-Warehouse)

When I opened your link, I didn't find anything related to this topic. „Zoyi ZT-XT1

Indam was referring to the original author of the component tester.

Zoyi have s support webpage at:
http://44.250.232.244/?support/ (http://44.250.232.244/?support/)

All available firmware for the different equipment is there.
Please read all posts from the beginning to learn about the issues found by members.

You don't need to use the IP, just use the official English Zotek/Zoyi website: https://zotektools.com/?support/
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: jebem on June 06, 2026, 09:25:32 pm
liutas
https://github.com/madires/Transistortester-Warehouse (https://github.com/madires/Transistortester-Warehouse)

When I opened your link, I didn't find anything related to this topic. „Zoyi ZT-XT1

Indam was referring to the original author of the component tester.

Zoyi have s support webpage at:
http://44.250.232.244/?support/ (http://44.250.232.244/?support/)

All available firmware for the different equipment is there.
Please read all posts from the beginning to learn about the issues found by members.

You don't need to use the IP, just use the official English Zotek/Zoyi website: https://zotektools.com/?support/ (https://zotektools.com/?support/)

Well, that IP address was given to me by the official Zoyi support via email.

In my location, for several days the web address was not answering at all (time out) and the DNS servers I tried didn't find a good IP address able to respond.

So, if you know the IP address of a web server/virtual address, you just bypass the DNS glitches that may occur during certain operations on the WWW.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: daveyk on June 15, 2026, 07:21:37 pm
Hey Scott.  Your testing did not see if those PCB pads under the Zif socket work.  If they do, I could not figure it out.  Looks like a nice place to test small SMT caps or SOT23 parts.  Those pads do not seem active in this model.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: SammysHP on June 15, 2026, 08:23:47 pm
Hey Scott.  Your testing did not see if those PCB pads under the Zif socket work.  If they do, I could not figure it out.  Looks like a nice place to test small SMT caps or SOT23 parts.  Those pads do not seem active in this model.
That can be checked with a continuity tester: The two pads on the left side are connected to pins 1+2 and the three pads on the right to pins 1+2+3.
Title: Re: Zoyi ZT-XT1 Transistor tester / multimeter
Post by: daveyk on June 16, 2026, 01:03:42 pm
"That can be checked with a continuity tester: The two pads on the left side are connected to pins 1+2 and the three pads on the right to pins 1+2+3."

So the two pads are for DIODEs and the SOT23 pads do work?  They both have a boarder of plastic do it should be easy to align a part for testing. It would be so nice if you could place a tiny smt cap, on those pads and find out its value.  Using the meter leads is hard for a little part. I tried, those two pads do not work for caps.

I wish one of these testers would some day state " this transistor is probably a mm3406", or something like that - lol.  Maybe set the part in it, and also provide the markings on it (naa, it will need a small camera to see the part).  Let it connect to AI via wifi; test the part and it tells you that it is okay and what it is.  In this day of SMT, we need something like that. heh heh

- Dave