Is a Rigol MSO5000 overkill for a hobbyist?

[coppice]

Is this piece of string too long for a hobbyist?

[alm]

and my old TDS3034 (1mV is the lowest sensibility)

For the TDS3000, try also taking a single shot capture to disable its 'analog persistence', which affects how noise is displayed.

I find square waves an easier way to visually gauge noise.

[trp806mo]

TDS in single shot

[Martin72]

At work we got SDS2104X+, 1104X-E and rigol ds1054Z and of course lecroy scopes.
When it´s interesting I can compare them on 2mVpp in the next week.

Tested on following scopes:
Rigol DS1054Z
Siglent SDS1104X-E
Siglent SDS2104X+
Lecroy Waversurfer 3024Z (Waverunner 9054 is on external cal.)
Lecroy HDO6034A

Source rigol awg, amplitude 2mVpp, Frequency 8Mhz
Settings on scopes : 1mV/Div., 50ns/Div, BWL 20Mhz, memory default/auto
SDS2104X+ 8bit and 10bit mode.

Pics attached...

[alm]

Thanks for doing those tests! The Lecroy Waversurfer and possibly the SDS1104X appear to have analog persistence enabled. Can you take screenshots with that disabled?

[Martin72]

Can check this tomorrow.
Did it quick in a break, because it´s for private joy..

[balnazzar]

If possible, try and set something different than a pure sine (more or less like what I did on the previous page) so you can see how the high resolution modes will kind of flatten the true signal.

[Martin72]

Hi,

I didn´t use any hi-res modes of the scopes*, the pics showing the "raw" behaviour.
But I can play a little bit around with it, when it´s interesting for others.

*) the 10 bit mode of the SDS2k+ is somekind special with it´s bandwithlimitation of appx 100Mhz.

[balnazzar]

Results with my AD2. Tried with its own awg and with the UNI-T awg I used to generate the screenshots with the 1104x-e. Pure sine waves. The results were identical.

TL;DR is that the AD2 seems to be incapable of managing signals <~20mVpp. I'd like you to tell me why. It's the too shallow memory? The sampling rate? The FE/ADC is 14 bit...

Note that the FFT still spots the frequency at 2mVpp quite clearly, no matter the signal being unrecognizable.

[egonotto]

Hello,

The Analog Discovery has only 2 sensitivity levels. Everything else is done using digital zoom. If I remember correctly, only the settings 500 mV/div and 5 V/div have the best resolution

Best Regards
egonotto

[balnazzar]

Hello,

The Analog Discovery has only 2 sensitivity levels. Everything else is done using digital zoom. If I remember correctly, only the settings 500 mV/div and 5 V/div have the best resolution

Best Regards
egonotto

That's not a good thing. Even the Owon vds1022i does much better at a few microvolts, no matter being 4X cheaper.

500 mV are *a lot*.

[egonotto]

Hello,

1 LSB is approximately 0.5 mV. If you add the noise, it is not surprising that the Analog Discovery performs poorly at 20 mV/div and below.

Best Regards
egonotto

[balnazzar]

Hello,

1 LSB is approximately 0.5 mV. If you add the noise, it is not surprising that the Analog Discovery performs poorly at 20 mV/div and below.

Best Regards
egonotto

But look at that.. It's a staircase wave at TWO Vpp. It souldn't have problems with it, right?
Wrong, the staircase is not even distinguishable.
The Siglent had shown it clearly at two *milli*Volt pkpk...

That's not acceptable, I'm considering returning this little sh*t.

[Anthocyanina]

Hello,

The Analog Discovery has only 2 sensitivity levels. Everything else is done using digital zoom. If I remember correctly, only the settings 500 mV/div and 5 V/div have the best resolution

Best Regards
egonotto

That's not a good thing. Even the Owon vds1022i does much better at a few microvolts, no matter being 4X cheaper.

500 mV are *a lot*.

The AD2 has a maximum absolute resolution of 320µV when below 500mV/ but the accuracy is +-10mV +-0.5% so it's definitely not great for super low level signals, but the 1022i also isn't great, and definitely not for microvolts. It has trouble with a 2mVpp signal, it can't trigger properly, and at 2mvpp you're already looking at a signal less than 1 division tall, but yeah, for low signal levels, the 1022i is better than the AD2

[balnazzar]

Owon vds1022i. The staircase is clearly recognizable.

[balnazzar]

The AD2 has a maximum absolute resolution of 320µV when below 500mV/ but the accuracy is +-10mV +-0.5% so it's definitely not great for super low level signals, but the 1022i also isn't great, and definitely not for microvolts. It has trouble with a 2mVpp signal, it can't trigger properly, and at 2mvpp you're already looking at a signal less than 1 division tall, but yeah, for low signal levels, the 1022i is better than the AD2

The staircase wave I threw at the AD2 is two Vpp. Not mVpp. It's not a low signal level.

[balnazzar]

The AD2 has a maximum absolute resolution of 320µV when below 500mV/ but the accuracy is +-10mV +-0.5% so it's definitely not great for super low level signals, but the 1022i also isn't great, and definitely not for microvolts. It has trouble with a 2mVpp signal, it can't trigger properly, and at 2mvpp you're already looking at a signal less than 1 division tall, but yeah, for low signal levels, the 1022i is better than the AD2

In your case the teeth are much more evident.. Did you do something exotic to set the scope? Thanks.

[Anthocyanina]

The AD2 has a maximum absolute resolution of 320µV when below 500mV/ but the accuracy is +-10mV +-0.5% so it's definitely not great for super low level signals, but the 1022i also isn't great, and definitely not for microvolts. It has trouble with a 2mVpp signal, it can't trigger properly, and at 2mvpp you're already looking at a signal less than 1 division tall, but yeah, for low signal levels, the 1022i is better than the AD2

The staircase wave I threw at the AD2 is two Vpp. Not mVpp. It's not a low signal level.

oh, that was not about the staircase but about this:

Results with my AD2. Tried with its own awg and with the UNI-T awg I used to generate the screenshots with the 1104x-e. Pure sine waves. The results were identical.

TL;DR is that the AD2 seems to be incapable of managing signals <~20mVpp. I'd like you to tell me why. It's the too shallow memory? The sampling rate? The FE/ADC is 14 bit...

Note that the FFT still spots the frequency at 2mVpp quite clearly, no matter the signal being unrecognizable.

[Anthocyanina]

This is quite strange, trying to post this, it tells me it has already been posted, and that changed the image of my previous reply, so posting with this text to see if that changed?:

Hello,

1 LSB is approximately 0.5 mV. If you add the noise, it is not surprising that the Analog Discovery performs poorly at 20 mV/div and below.

Best Regards
egonotto

But look at that.. It's a staircase wave at TWO Vpp. It souldn't have problems with it, right?
Wrong, the staircase is not even distinguishable.
The Siglent had shown it clearly at two *milli*Volt pkpk...

That's not acceptable, I'm considering returning this little sh*t.

How many steps does your staircase have? and what frequency? Here's what mine looks like with 9 steps and at 3.472MHz, really bad, but not as bad as in your screenshot o.o

[Anthocyanina]

The AD2 has a maximum absolute resolution of 320µV when below 500mV/ but the accuracy is +-10mV +-0.5% so it's definitely not great for super low level signals, but the 1022i also isn't great, and definitely not for microvolts. It has trouble with a 2mVpp signal, it can't trigger properly, and at 2mvpp you're already looking at a signal less than 1 division tall, but yeah, for low signal levels, the 1022i is better than the AD2

In your case the teeth are much more evident.. Did you do something exotic to set the scope? Thanks.

nope, all the settings are on the screenshot, i replicated the settings from yours, and used a 9 step staircase

[balnazzar]

7 steps rising, 7 falling, 4 MHz.

Mh.. Try to set a trapezoidal wave on your AD2, even at the voltages more congenial to the device. Say 500 mV or 5 V.

Can you confirm that already at 2 MHz the wave is heavily distorted and at 5 MHz it's no longer distinguishable as a trapezoidal? Same at low frequencies, e.g. 100 Hz.

And that no matter the voltage.

Did the same with an external awg. Same results. It's the scope.

I'm starting wondering what exactly I can observe with it.
Not low level signals, OK. But not even high level ones, it seems.

In any case, thanks for the experiments you are performing

[Anthocyanina]

7 steps rising, 7 falling, 4 MHz.

Mh.. Try to set a trapezoidal wave on your AD2, even at the voltages more congenial to the device. Say 500 mV or 5 V.

Can you confirm that already at 2 MHz the wave is heavily distorted and at 5 MHz it's no longer distinguishable as a trapezoidal? Same at low frequencies, e.g. 100 Hz.

And that no matter the voltage.

Did the same with an external awg. Same results. It's the scope.

I'm starting wondering what exactly I can observe with it.
Not low level signals, OK. But not even high level ones, it seems.

In any case, thanks for the experiments you are performing

The fastest I can get it to go is 2.6MHz because of the arb sampling rate, but this is how it looks like. If you look at the FFT there is a lot of content past the bandwidth of the AD2 scope, so it will smooth out at higher frequencies. Here's also what the trapezium waveform from the AD2 generator looks like on the AD2, but that's also because the generator is very limited in bandwidth. It looks smoothed, but it also doesn't look great on a bench scope

Edit: was able to set the stairs up for 4MHz, added a picture of that

[egonotto]

Hello,

the Analog Discovery has about 15 ns rise time.

At 0.5 MHz you can still see the stages well. Not anymore at 2.5 MHz. For comparison with another better generator. The limit is set by the scope but also by the generator of Analog Discovery.

A stage then takes only about 28 ns. This corresponds to a rectangle of almost 20 MHz. You can't be angry with Analog Discovery for not being able to do that.

Best Regards
egonotto

[2N3055]

Complete bollocks.

Agree. Your posts are mostly that... Which is a shame really, because you seem to be intelligent person that could do so much better than that.

There's a forum member "tggzzz" with an applicable sig:

Glider pilot's aphorism: "there is no substitute for span".
Retort: "There is a substitute: skill+imagination. But you can buy span".

And in this case his sig means: you can try to twiddle and invent all kind of tricks, but you can simply buy a scope that works well in a first place.

Did you ever show any of people that asked you any of your measurements and setups with all the scopes and amplifiers you recommend ?

[balnazzar]

Thanks folks for having tested & provided feedback about the AD2.

It's a bit more lmited that I thought.