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

[tol]

Is there any way to fix the nasty red colors after voltages above 220 volts?
 

Unfortunately, there is no open source firmware for this device. You will have to live with it. Or buy a different multimeter

One user here tried to make an alternative firmware some time ago (with some promising results), but he disappeared without a trace... all we could understand is that it is not an easy thing to make an alternative firmware for this device and probably it doesn't worth time and effort.

[chebo]

Unfortunately, there is no open source firmware for this device. You will have to live with it. Or buy a different multimeter

One user here tried to make an alternative firmware some time ago (with some promising results), but he disappeared without a trace... all we could understand is that it is not an easy thing to make an alternative firmware for this device and probably it doesn't worth time and effort.

"Lord, grant me the serenity to accept the things I cannot change, the courage to change the things I can, and the wisdom to know the difference." 

[beamertt]

Release notes says: Fixed the issue of automatic restart after saving waveforms in V1.6.3.

It's just my IMHO, but it feels like the latest versions have more lagging than the initial 1.3-1.4 versions. But it's just how I feel, I didn't make any tests.

Yep, I also noted it. If for instance you press multiple times to change the timebase then sometimes there seems to be a hick-up in response and the screen seems to momentarily freeze...

[tol]

Yep, I also noted it. If for instance you press multiple times to change the timebase then sometimes there seems to be a hick-up in response and the screen seems to momentarily freeze...

It's not only GUI problem but signal viewing as well. For example, if you watch some slow signal in realtime (for example, a capacitor discharge), you can see how it freezes the signal every several seconds, not for a long time, but it's not really realtime anyway. I think the same freezing happens when grabbing faster signals, but we cannot see it because they are too fast. However, it may explain why the trigger skips many signals in my tests - the device is just periodically busy with some unknown stuff and it doesn't have enough CPU time to watch the trigger at the same time I want to install some really old firmware to see if the trigger skips signals there as often as in the latest firmware.

[indman]

I want to install some really old firmware to see if the trigger skips signals there as often as in the latest firmware.

I currently have the old version 1.3.8 installed. I've discarded all the updates that came after it as junk.
1.3.8 also has a lot of bugs, so that's my opinion.

[Edmiri]

This is the only solutuon to this problem.

https://www.reddit.com/r/Damnthatsinteresting/s/20F0NaHAb4

[Faeren]

Does the ZT-703S have 512kpts or 128 kpts of memory depth? This thread and a few other sources say 512kpts, but the product page says 128kpts?

[EU1]

Has anyone figured out what the new "Sample: HD/Peak" setting actually does in the latest ZT-703S firmware?
I noticed that in HD mode the waveform looks much cleaner - less noise - but the scope sometimes seems to switch between a clean and a noisy state depending on the input signal. It makes me wonder if HD mode just enables some kind of automatic low-pass filtering when the high-frequency component is small.
On some signals, HD and Peak look completely identical, which really makes it seem like the device is dynamically changing modes based on the signal.
If that's true, it feels a bit like a software trick rather than real "high definition" sampling. Has anyone else observed this behavior or dug into how it actually works?

[chebo]

Does the ZT-703S have 512kpts or 128 kpts of memory depth? This thread and a few other sources say 512kpts, but the product page says 128kpts?

I think you can simply calculate this on the screen. Stop the sweep and stretch the signal so you can see the distance between the points. Then compress the signal so you can see its total stored length. Then divide one by the other to get the number of stored points.

[Faeren]

Does the ZT-703S have 512kpts or 128 kpts of memory depth? This thread and a few other sources say 512kpts, but the product page says 128kpts?

I think you can simply calculate this on the screen. Stop the sweep and stretch the signal so you can see the distance between the points. Then compress the signal so you can see its total stored length. Then divide one by the other to get the number of stored points.

True!

Interestingly on measuring this, when I set to high speed mode and minimum time-base, I get a record length of 422.9uS, approximate calculation based on the stated rating of 280MSa/s confirms it's definitely around 128kpts, however if I go to calculate the sample rate from that (128,000/(422.9*10^-6)) I'm getting a sample rate of ~303MSa/S, which exceeds the spec quite nicely. It seems unlikely the record length would be some weird figure slightly less than 128k, or could there be a reason for that?

I can't seem to zoom in far enough to accurately measure the distance between points, as if I set the timebase higher the scope doesn't let me zoom in far enough to differentiate points.

[JayDee_2025]

How are you guys updating to 164? Mine says it needs another 92k to be able to hold the firmware file.

[zenon]

How are you guys updating to 164? Mine says it needs another 92k to be able to hold the firmware file.

Just erase everything from memory and try again.

[JayDee_2025]

How do I delete stuff in memory? When I plug it into pc all I see is a firmware folder. no other files other than that.

[mebel]

How do I delete stuff in memory? When I plug it into pc all I see is a firmware folder. no other files other than that.

Restore to defaults from oscilloscope menu

[hpm]

How are you guys updating to 164? Mine says it needs another 92k to be able to hold the firmware file.

same here, memory size too low, no memory to be deleted etc. switching on/off didn't help either, switching between normal and high runmode back and forth did the trick for me.

[BOPOH]

same here, memory size too low, no memory to be deleted etc. switching on/off didn't help either, switching between normal and high runmode back and forth did the trick for me.

https://www.eevblog.com/forum/testgear/new-zoyi-multimeteroscilloscopes-zt-70xs-up-to-50mhz250msps-(nov-2022)/msg5874304/#msg5874304
1.4.2 / 1.5.5
menu -> MoreApps -> menu (ImgView) ->  (There is nothing about Fn keys on the screen) F3 -> F3 (format)

[hpm]

same here, memory size too low, no memory to be deleted etc. switching on/off didn't help either, switching between normal and high runmode back and forth did the trick for me.

https://www.eevblog.com/forum/testgear/new-zoyi-multimeteroscilloscopes-zt-70xs-up-to-50mhz250msps-(nov-2022)/msg5874304/#msg5874304
1.4.2 / 1.5.5
menu -> MoreApps -> menu (ImgView) ->  (There is nothing about Fn keys on the screen) F3 -> F3 (format)

That didn't work either,
only switching between normal and high runmode back and forth did it me.

[cncjerry]

my 703 has a weird problem I just noticed.  Measuring straight DC and AC it is very accurate.  When I try to measure a small AC value on a 15VDC supply, the AC displayed jumps all over the place.  I've tested and scoped the DC supply and the AC is about 20mv.  The meter display jumps up to 14v but generally flickers about .5V.  In AC mode with the leads crossed, it reads 0V as it should.  Thoughts?

Jerry

[krondor]

Does anyone know if the Zoyi firmware files can be installed in the Aneng branded variant as well?

[xKertx]

Does anyone know if the Zoyi firmware files can be installed in the Aneng branded variant as well?

Yes. It's the same device with different labels.

[FixyMixy]

I've just tested firmware ZOYI-703S-FW-V164 ( from http://www.szzotek.com/h-col-159.html ).
And still no luck: wobbly waveform above few MHz.

[beamertt]

I've just tested firmware ZOYI-703S-FW-V164 ( from http://www.szzotek.com/h-col-159.html ).
And still no luck: wobbly waveform above few MHz.

For me some things improved compared to V1.57 like for instance better waveform display at higher frequencies and improved triggering on single events. But the triggering is still far from perfect depending on horizontal timebase, mainly in the ns range.
Also weird to me is that in the High Speed Run mode the frequencies above 20Mhz or so look worse compared to the Normal Run mode....
Somehow, in High Speed Runmode, at the higher frequencies, there seems to be noise on top of the waveform. Interestingly the waveform on channel 1 seems to improve if you also enable Channel 2, even when not using it???
For now I only use it in the Normal Run mode and have no big issues till frequencies around 30Mhz or so.

Hopefully the next firmware which will fix all issues without introducing new ones   

But still love this meter for the simple scope functions and it's accurate multimeter functionality.

[FixyMixy]

For me some things improved compared to V1.57 like for instance better waveform display at higher frequencies and improved triggering on single events. But the triggering is still far from perfect depending on horizontal timebase, mainly in the ns range.

Trigger issues are bad. But, IMHO, it's even more important to have accurate waveform representation. On V1.56 I can move (false) trigger point to see the sparse signal event, but it's real waveform, not made up by the bug.

[beamertt]

I went back from V157 to V156 because V157 was really nok. V156 was better and you could work around most of the issues indeed. V164 is different (not better) but I think I leave it on till the next upgrade...

[Payne]

I have noticed, if the signal is somewhat unstable at 100ns using both channels then pressing F3 (TRIG), will make  triggering become stable, but if you leave F3 for another function, the signal becomes unstable again. Also just selecting the blue channel in "Vol/Time" will make the signal stable

I have FW 1.6.4