To clarify, this EEV Blog thread from 2023 was started by me:
https://www.eevblog.com/forum/testg...2x-e-200-mhz-digital-oscilloscope-2-channels/

I raised some issues with my SDS1202X-E (purchased new from Amazon in mid 2020). I didn't begin using it until early 2023, and ran into issues that might be related to original defects with the new unit.

There are many so-called experts and even Siglent vendors on EEVblog that responded in the thread. None really helped, and the issue remains (more below).
I pushed in the issue, and was banned from EEVBlog as result.

The main issue is what I might describe as: a long time to "settle in" to RELIABLE and noise-free operation (after morning power up -- say if the 1202 was shut down for the night).
Because of the echo-chamber mentality of the EEV gang (see that absurd thread), it took me a long time to establish that the 1202 might indeed be defective (that I got, and am stuck with a bum unit).

Examples:

If I completely power down the 1202 for, say 5 min -- even, unplugging the 1202 from AC -- but leaving the probes in situ in the same experiment, and then re-power the 1202, I can resume the experiment with noise-free and reliable results (corroborated with my Tek 465).
But it is when I power off for the night, and re-resume, that I run into "noisy" signals and weird results.
The idiot-button, AUTOSET , should default the user to some kind of usable results; but even the functionality of this button (function) is useless until the 1202 has been on ("warming up"???) for at least 20 min.

And when it begins working, the 1202 is normal and easy to use.

Questions:

So what's wrong with my unit? E.g. bad solder joints or caps? Do I need to take it apart and begin looking for defects on the PCB or caps?

 

The first solution is always to download and update with the latest firmware version.

As a rule, I never use the AUTOSET button. It is there for dummy users.

Lastly, never jumped to conclusions. I encountered two situations where sensitive instruments were malfunctioning at certain hours of the day or night. In one case, unexpected data was recorded at a certain time in the early morning. After we installed a surveillance camera, we discovered that the anomaly was correlated to the time the cleaner entered the lab. Just opening the door cause a temperature change in the room.

In the second case, signal noise level increased during the day and improved after working hours. I traced it to a noisy power supply in a PC in a lab on a lower floor. It turned out that the graduate student always turned on his computer when he arrived in the morning and then turned it off before leaving at the end of the day.

 

The first solution is always to download and update with the latest firmware version.

I criticized this same repeated reply, that MANY gave in the EEV Blog thread.
If you go to that thread, you'll note I was running the latest FW at the time. As were others.
What I experience is a very, very serious issue with the Siglent. They would've corrected this years before launch of the first batch of the model.
And my 1976 Tek 465 has no similar issues.
There might not be an easy fix.

 

We have 20 Siglent SDS1202X-E running in our lab every day. Not one of them has a problem.

 

We have 20 Siglent SDS1202X-E running in our lab every day. Not one of them has a problem.

Are they always plugged in. (Standby light should pulse when "OFF")

 

I wish there was a firmware setting to disable the AUTOSET button. Even on the latest 2 series TEK, it seldom has a sane display after using it.

 

Are they always plugged in. (Standby light should pulse when "OFF")

Yes. They are plugged in on workbench power strip.

 

I wish there was a firmware setting to disable the AUTOSET button. Even on the latest 2 series TEK, it seldom has a sane display after using it.

The AUTOSET works just fine, and I even find it convenient ... after the damn thing settles down. I think the issue may be related to unplugging the unit. I'll have to take the cover off and see if the CMOS battery is okay.

 

Sometimes you have just purchased an ill-humored device and the only path forward is to toss it and buy another.

I have had just that (in a different time and place) - not faulty enough for a warranty claim but not good enough to be usable, and the best path forward is to write off the aggravation and start again.

 

To clarify, this EEV Blog thread from 2023 was started by me:
https://www.eevblog.com/forum/testg...2x-e-200-mhz-digital-oscilloscope-2-channels/

I raised some issues with my SDS1202X-E (purchased new from Amazon in mid 2020). I didn't begin using it until early 2023, and ran into issues that might be related to original defects with the new unit.

There are many so-called experts and even Siglent vendors on EEVblog that responded in the thread. None really helped, and the issue remains (more below).
I pushed in the issue, and was banned from EEVBlog as result.

The main issue is what I might describe as: a long time to "settle in" to RELIABLE and noise-free operation (after morning power up -- say if the 1202 was shut down for the night).
Because of the echo-chamber mentality of the EEV gang (see that absurd thread), it took me a long time to establish that the 1202 might indeed be defective (that I got, and am stuck with a bum unit).

Examples:

If I completely power down the 1202 for, say 5 min -- even, unplugging the 1202 from AC -- but leaving the probes in situ in the same experiment, and then re-power the 1202, I can resume the experiment with noise-free and reliable results (corroborated with my Tek 465).
But it is when I power off for the night, and re-resume, that I run into "noisy" signals and weird results.
The idiot-button, AUTOSET , should default the user to some kind of usable results; but even the functionality of this button (function) is useless until the 1202 has been on ("warming up"???) for at least 20 min.

And when it begins working, the 1202 is normal and easy to use.

Questions:

So what's wrong with my unit? E.g. bad solder joints or caps? Do I need to take it apart and begin looking for defects on the PCB or caps?

I have an SDS1204X-E, purchased in Dec 2019, from Amazon, how can I help?

 

The AUTOSET works just fine, and I even find it convenient ... after the damn thing settles down. I think the issue may be related to unplugging the unit. I'll have to take the cover off and see if the CMOS battery is okay.

No CMOS battery in these as they don't have a RTC.

 

Boot it and let it run for ~30 mins then do the Self Cal, should take 5-10 minutes, maybe less.
Disconnect all probes etc as prompted before the Self Cal starts.

Report here any changes in behaviour.

 

When the guy who banned me from EEV vlogged about this model in 2017, he was gushing all over it ... except maybe the cheap electro caps...

 

Boot it and let it run for ~30 mins then do the Self Cal, should take 5-10 minutes, maybe less.

I did the SelfTest yesterday. No issues.
About that "let it run for ~30 mins" -- why that long? Warm up? Settling time.
The damn thing does run warm and noisy (fan).
Are there any mods or hacks that might help with stability? Replace cheap electros with better caps. Maybe more bypass caps across the electros. EMI/RFI filter on the mains.
I do have some parts from my audiophile hobby.

 

I did the SelfTest yesterday. No issues.
About that "let it run for ~30 mins" -- why that long? Warm up? Settling time.

Good, no issues self identified.
Warm up to be stable for the Self Cal to correctly calibrate/adjust channel gains etc.

No different to any other time of equipment before manual or in this case auto adjustment.

The damn thing does run warm and noisy (fan).

The fan does keep internal temps stable which results in better accuracy once temps have stabilized.
Still despite the noise I'd rather have a fan cooled instrument than a top vented instrument that let any sort of gunk inside for humidity to make it start corroding the instruments guts.....lost a TDS2012B like ths !

Are there any mods or hacks that might help with stability?

No.
Don't forget you have a highly sensitive medium BW scope that will display unwanted noise and probing techniques need be sufficiently good to minimise or eliminate unwanted signals.

About this ^^
I have on occasion had customers insist the scope we supplied is faulty but we briefly test all before dispatch and typically the noise they see is from a nearby SMPS wallwart spewing EMI/RFI into their workspace.....yes these scopes will see this muck.
We have advised hooking the scope to a DUT with settings that show noise and then proceed to turn OFF appliances and wallwarts one by one to find the culprit that a DSO can see but a CRO is blind to.
Don't discount this and you can do your own tests with a probe reference (Gnd) lead clipped to the probe grabber to form a RF loop to sniff all manner of devices.
This non-contact RF loop trick is also handy for assessing if a SMPS is oscillating properly without the need to make contact with potentially lethal voltages. Here we would consult the SMPS controllers datasheet and note the frequency of operation so with a scope trigger correctly deployed we would see the frequency in the top right of the scopes display.

 

To clarify, this EEV Blog thread from 2023 was started by me:
https://www.eevblog.com/forum/testg...2x-e-200-mhz-digital-oscilloscope-2-channels/

I raised some issues with my SDS1202X-E (purchased new from Amazon in mid 2020). I didn't begin using it until early 2023, and ran into issues that might be related to original defects with the new unit.

There are many so-called experts and even Siglent vendors on EEVblog that responded in the thread. None really helped, and the issue remains (more below).
I pushed in the issue, and was banned from EEVBlog as result.

The main issue is what I might describe as: a long time to "settle in" to RELIABLE and noise-free operation (after morning power up -- say if the 1202 was shut down for the night).
Because of the echo-chamber mentality of the EEV gang (see that absurd thread), it took me a long time to establish that the 1202 might indeed be defective (that I got, and am stuck with a bum unit).

Examples:

If I completely power down the 1202 for, say 5 min -- even, unplugging the 1202 from AC -- but leaving the probes in situ in the same experiment, and then re-power the 1202, I can resume the experiment with noise-free and reliable results (corroborated with my Tek 465).
But it is when I power off for the night, and re-resume, that I run into "noisy" signals and weird results.
The idiot-button, AUTOSET , should default the user to some kind of usable results; but even the functionality of this button (function) is useless until the 1202 has been on ("warming up"???) for at least 20 min.

And when it begins working, the 1202 is normal and easy to use.

Questions:

So what's wrong with my unit? E.g. bad solder joints or caps? Do I need to take it apart and begin looking for defects on the PCB or caps?

That scope cant be powered off from its control panel, only shutdown into standby mode. To 100% power off you must disconnect from the power outlet, so when you say "power off" what exactly do you mean?

Can you do a factory reset?

 

I did the SelfTest yesterday. No issues.
About that "let it run for ~30 mins" -- why that long? Warm up? Settling time.
The damn thing does run warm and noisy (fan).
Are there any mods or hacks that might help with stability? Replace cheap electros with better caps. Maybe more bypass caps across the electros. EMI/RFI filter on the mains.
I do have some parts from my audiophile hobby.

As I said I have the 4 channel version of the same scope, I'd be happy to run through some tests and take screen shots etc, then you can compare. I recently upgraded to a SDS1204X HD,but still have SDS1204X-E.

 

I did the SelfTest yesterday. No issues.
About that "let it run for ~30 mins" -- why that long? Warm up? Settling time.
The damn thing does run warm and noisy (fan).
Are there any mods or hacks that might help with stability? Replace cheap electros with better caps. Maybe more bypass caps across the electros. EMI/RFI filter on the mains.
I do have some parts from my audiophile hobby.

Tell me, you bought it in 2020 but say you didn't use it until 2023, so where was the unit during that three year period? in a human habitat? was it never unpacked until 2023? was it ever subject to very hot or cold temperatures? was it possibly subject to vibration or smoke etc (like was it stored on a shelf in garage for three years).

You know you can get it recalibrated, summarize your concerns beforehand, the calibration lab might well see your problem. Where do you live?

Finally, someone did a superb in-depth review of the 4 channel version, I event printed it out, highly detailed like 50 pages PDF with lots of screenshots, I learned quite a lot from that review, if you've never seen it will try to recall where I downloaded it.

 

@oh_uh_okay

OK here is the in-depth review of the Siglent SDS1x04X-E, the stuff applies equally to the SDS1202X-E as well (to a degree).

Part 1
Part 2

Total 50 pages, 25 pages to each part.