Oscilloscope

[Tinkerer]

My SDS8102V OWON oscilloscope died after 7 years of service.

What would be a good replacement?

Does anybody have experience with PICO scopes?
To be able to use the large computer screen seems interesting for me as my eyes are not that good anymore.

Any suggestions?

[KingJL]

My SDS8102V OWON oscilloscope died after 7 years of service...

What would be a good replacement?

A digilent Analog Discovery 2 (if you can get it... they have reserved all stock to students and professors due to supply shortage) or PICO scope.

Does anybody have experience with PICO scopes?

I believe @Ferric Toes is using a PICO scope. He seemed impressed with it's operation/capabilities.

To be able to use the large computer screen seems interesting for me as my eyes are not that good anymore.

Also these newer digital USB scopes have a LOT of capabilities that were not available/affordable with traditional o'scopes.

[Tinkerer]

Thank you for the feedback.

I looked for the Analog Discovery 2, nowhere to find. Out of stock.

I have a Hantek DSO 4254C, unfortunately, the screen is relatively small. It connects to the computer by USB 2, but the screen update rate is about 2Hz, rather useless for analog signals in the nano seconds.
Maybe I do something wrong?

[KingJL]

Thank you for the feedback.

I looked for the Analog Discovery 2, nowhere to find. Out of stock.

Like I said, all stock is reserved for educational sales. Keep a check on ebay... every once in a while, a college student gets rid of one. I snagged one about off of ebay a month ago. I was going to get the Pico scope 2205A if I couldn't find the Analog Discovery 2.

I have a Hantek DSO 4254C, unfortunately, the screen is relatively small. It connects to the computer by USB 2, but the screen update rate is about 2Hz, rather useless for analog signals in the nano seconds.
Maybe I do something wrong?

Unfortunately, I do not think you are doing anything wrong. I have a 2C70... same thing when connected to the computer by USB the screen update is to slow to be useful. And the 2C70 screen is way to small for normal use. And support for Hantek product is poor to non-existent!

If you cannot find the Analog Discovery 2, I'd go with the Pico scope 2000 or 3000 series ( 25Mhz or higher ). Reach out to @Ferric Toes for feedback on the Pico scope.

[Tinkerer]

Thank you all for the help.

After much hesitation I bought the PICOSCOPE 5442D. Is it an overkill?

It took about 1 hour of to go through just a fraction of the features. Very quickly I found the noise that is downgrading my signal. I had been looking for that noise with the Hantek and the Owon for months, without finding it.

Compare the price of the scope to months of work? I can say with confidence it is not overkill. I should have taken the step a long time ago.

Now it is a matter of finding the source or origin of the noise.

Ps. for admin: By mistake I started a new thread for oscilloscopes, while there is already a thread. It might be good to merge the 2 threads.

[ivconic]

...Now it is a matter of finding the source or origin of the noise...

Source is most probably pc computer attached to your new PICOSCOPE 5442D!!!

[Tinkerer]

Source is most probably pc computer attached to your new PICOSCOPE 5442D!!!

Thank you for the feedback.
Checked output of ADC with scope probes connected and without. No difference. Noise the same.
Noise is a periodic oscillation about every 700ms. Total duration of about 200us. Oscillation starts low and increases to a peak and then decays fast.

[ivconic]

Thank you for the feedback.
Checked output of ADC with scope probes connected and without. No difference. Noise the same.
Noise is a periodic oscillation about every 700ms. Total duration of about 200us. Oscillation starts low and increases to a peak and then decays fast.

Sounds like inadequate capacitor value.

[rickb]

That's a pretty good description of squegging.

https://en.wikipedia.org/wiki/Squegging

[Tinkerer]

That's a pretty good description of squegging.

https://en.wikipedia.org/wiki/Squegging

Thank you for the feedback. The link really explains well what is happening.

Squegging or motorboating, yes this is one of my problems.

This PI runs at a repetition rate of 20,000Hz. It is designed to find targets with a TC of less than 1us.
It is doing a good job in exciting the targets and gives me 2" of detecting distance...sometimes.
The problem is noise.
Sometimes we get the output noise level down to 600uV, other times the noise is up at 8mV.