New Zoyi multimeter+oscilloscopes - ZT-70xS, up to 50MHz/250MSps (nov 2022)

[OLderDan]

both the more apps and external work over all ranges and signal types, checked with the z703s and my dso2d15. I haven't checked since upgading and downgrading the firmware, but I have no reason to believe anything has changed.

[Phb]

Same "glitch" in my case.
Have you check if the signal generator really works?
Not for me, You can see may last post and the video

Would you be able to get a warranty claim from whoever you purchased it from?

Alternatively, you can try the information here to have your issue resolved.

http://www.szzotek.com/h-col-160.html

Its a mandarin based page, but you can use translate to access it. And the WeChat link seems interesting, although I have never tried it. The shipping from where you are from may not be be financially viable though.

[fortis]

Just made a new probe cover with a thinner bottom to fit standard connectors

https://www.thingiverse.com/thing:7053840

[rx485]

Hi! I bought myself a ZT-703S. After 2 months of use, I noticed that the oscilloscope on channel 1 with the probe disconnected began to underestimate at x1 by 300 mV, and at x10 by about 3 V. When applying a signal, the signal shifts by 300 mV down along the y axis. The built-in calibrator does not help. I also tried to flash it to the previous firmware, the problem remained. Maybe someone has encountered such a problem.

[Phb]

........ channel 1 with the probe disconnected began to underestimate at x1 by 300 mV, and at x10 by about 3 V. When applying a signal, the signal shifts by 300 mV down along the y axis.

The built-in calibrator does not help. I also tried to flash it to the previous firmware, the problem remained. Maybe someone has encountered such a problem.

Have you tried the "Default" option and then the "Calibrate" (with probes disconnected) menu buttons?

As per the pict below?

[rx485]

Hi! Yes, I tried it, the calibration function showed calibration failure. I think I fed too much signal to the oscilloscope and didn't even notice, which led to this signal distortion. I'm on a business trip now and I don't have the opportunity to disassemble the 703 to make sure the amplifier circuits are working properly. I'll come back in a couple of days and look into this problem more thoroughly.

[mebel]

https://drive.google.com/file/d/1did2_dDTP_rK_eO7O9-joANWN-guBZ_P/view

V157 Version Upgrade details:

1.Update: Fixed the triggering issue at 250ns

[MiroS]

probe disconnected began to underestimate at x1 by 300 mV, and at x10 by about 3 V

Are you located close to transmitter jamming GPS signal ?

[008nothing]

Hello, recently i tried using the zt-703 to read a dual signal waveform (don't know if that's the correct term) but obviously it didn't work. Our work scope did read both waveforms in a single channel easily as you can see in the attached photos. It there a way that i could make the zt-703 do that or is it a hardware issue?

[Aldo22]

Hello, recently i tried using the zt-703 to read a dual signal waveform (don't know if that's the correct term) but obviously it didn't work. Our work scope did read both waveforms in a single channel easily as you can see in the attached photos. It there a way that i could make the zt-703 do that or is it a hardware issue?

How do you create such a waveform on one channel?

[008nothing]

To be totally honest i am not sure ,we have to take some measurements and chance the capacitance of the circuit to try to ,among other things, align the 2 waveforms but i have no idea how they are generated as i am pretty new to this job and i am just learning the basics for now

[kloetpatra]

To be totally honest i am not sure ,we have to take some measurements and chance the capacitance of the circuit to try to ,among other things, align the 2 waveforms but i have no idea how they are generated as i am pretty new to this job and i am just learning the basics for now

This has nothing to do with ZT-703. Also your second picture is so bad that you can't even read anything. How do you think someone in particular can help.

This is oscilloscope basics and is related to sample rate and waveform update rate.
If the time base setting is faster, the acquisition rate is faster than the screen is able to display. Then several acquisitions are overlayed and displayed at the same time. The behaviour will vary between different oscilloscope models. There are possibilities that prevent that:
- using the "Single" mode
- choosing a slower time base
- using the "trigger hold off" function to reduce the acqusition rate

[008nothing]

To be totally honest i am not sure ,we have to take some measurements and chance the capacitance of the circuit to try to ,among other things, align the 2 waveforms but i have no idea how they are generated as i am pretty new to this job and i am just learning the basics for now

This has nothing to do with ZT-703. Also your second picture is so bad that you can't even read anything. How do you think someone in particular can help.

This is oscilloscope basics and is related to sample rate and waveform update rate.
If the time base setting is faster, the acquisition rate is faster than the screen is able to display. Then several acquisitions are overlayed and displayed at the same time. The behaviour will vary between different oscilloscope models. There are possibilities that prevent that:
- using the "Single" mode
- choosing a slower time base
- using the "trigger hold off" function to reduce the acqusition rate

I saw it when i went to post it but i don't have another picture and don't know when i'll get the chance to take another one. but what i wanted to show was that with the same signal one was showing one waveform while the other 2 waveforms. The desired result for me in this instance it to get 2 waveforms to show .And i am wandering if that is possible with the zt-703. The signal usually is in the range of 5-17Khz) and the voltage from some mV to 10V. Currently the waveform seems to go back and forth the 2 and seems unstable.

[Aldo22]

If the two waveforms are “real”, then measure them with both channels. If not, what do you want to do with that?
Normally, two signals on one channel add up as in the screenshot below (magenta).

[kloetpatra]

I saw it when i went to post it but i don't have another picture and don't know when i'll get the chance to take another one. but what i wanted to show was that with the same signal one was showing one waveform while the other 2 waveforms. The desired result for me in this instance it to get 2 waveforms to show .And i am wandering if that is possible with the zt-703. The signal usually is in the range of 5-17Khz) and the voltage from some mV to 10V. Currently the waveform seems to go back and forth the 2 and seems unstable.

No, you will never have the ZT-703 showing this modulated waveform like the Fluke 190-202. You can use the "persist" function to overlay multiple waveforms. Compared to the $5000 Fluke the ZT-703 is a toy and still has many bugs. However, your observation is not a bug, rather a limitation of the hardware and the way they implemented the waveform display.

Currently the waveform seems to go back and forth the 2 and seems unstable.

sounds like an asynchronous triggering problem which is totally normal for such kind of signal.

[008nothing]

I saw it when i went to post it but i don't have another picture and don't know when i'll get the chance to take another one. but what i wanted to show was that with the same signal one was showing one waveform while the other 2 waveforms. The desired result for me in this instance it to get 2 waveforms to show .And i am wandering if that is possible with the zt-703. The signal usually is in the range of 5-17Khz) and the voltage from some mV to 10V. Currently the waveform seems to go back and forth the 2 and seems unstable.

No, you will never have the ZT-703 showing this modulated waveform like the Fluke 190-202. You can use the "persist" function to overlay multiple waveforms. Compared to the $5000 Fluke the ZT-703 is a toy and still has many bugs. However, your observation is not a bug, rather a limitation of the hardware and the way they implemented the waveform display.

Currently the waveform seems to go back and forth the 2 and seems unstable.

sounds like an asynchronous triggering problem which is totally normal for such kind of signal.

Thank you, makes sense that those limitations exist in this price point, i was just making sure as i can't really understand how the fluke even does 2 signals in one channel work without them getting added to each other (like the person above suggests).

[Aldo22]

I'm beginning to understand. 
kloetpatra is right, this is a modulated waveform.
The Zeeweii DSO2512g can display something like that.
It depends on where the trigger is set.
With a stop, of course, you only see a single trace.
On the DSO2512g you don't need to activate persistence for this.

But I'm still not quite sure what that's good for.

@008nothing: Is that what you are looking for?

[008nothing]

I'm beginning to understand. 
kloetpatra is right, this is a modulated waveform.
The Zeeweii DSO2512g can display something like that.
It depends on where the trigger is set.
With a stop, of course, you only see a single trace.
On the DSO2512g you don't need to activate persistence for this.

But I'm still not quite sure what that's good for.

@008nothing: Is that what you are looking for?

yup, i think that's what i was going for. Mostly out of curiosity as at work we have to use the fluke ones because of certifications e.t.c.

[Aldo22]

yup, i think that's what i was going for. Mostly out of curiosity as at work we have to use the fluke ones because of certifications e.t.c.

OK, but I suspect this is still some kind of triggering artifact.
The signal probably looks more like the attached screenshot (magenta). That's 17kHz and 5kHz added together.

[mebel]

Anybody knows if custom firmware project is dead?

[Edmiri]

I hope not.

[rx485]

Hello! Can you tell me the marking of these two components on the first input of the Zoyi ZT-703? 1: 8091 is ad8091, 2 is TVS diode? Did I understand correctly?

[PerranOak]

When they update the firmware do they update the manual, e.g. use of FFT?

[eljjc]

I haven’t seen any updated manual for the ZT-703S corresponding to recent firmware updates.

Regarding the FFT feature: from what I’ve observed, the X-axis (frequency scale) seems to be tied directly to the selected timebase. For example, if you set the timebase to 20 µs/div, the FFT X-axis corresponds to 50 kHz/div. So the frequency range displayed changes depending on your timebase setting.

As for the Y-axis, it looks like they normalize the highest peak rather than displaying an absolute amplitude scale. So it’s more useful for identifying frequency components than for precise amplitude measurements.

Hope that helps!

[kloetpatra]

I don't know why nobody mentioned it in this thread yet, but Zoyi used the wrong charge controller ME4086B which has charge termination at 4.35V. Correct 4.2V one would be ME4086A. Zoyi should definitely do a recall before they put houses on fire.
I wonder if newer devices use the correct one?

Big thanks to @BRN who found this issue. Definitely check out his thread: https://www.eevblog.com/forum/testgear/zoyi-zotek-zt-703s-fire-hazard-while-charging/