One needs understand many cheap DSO's offer very limited sensitivity in that as every measurement we take actually effect the value of the measurement value itself. This is why we use the lower loading 10x probes in preference to 1x probes.
When limited sensitivity is offered, say 50mV/div, when used with the preferred 10x probe the actual max sensitivity becomes 500mV/div, a level that becomes somewhat useless for accurate low level measurements.
One must take care to understand the basics when selecting measurement tools.

 

Not only that, but in my experience several of these models lack an anti-aliasing filter, which can throw you off in case the signal gets near the maximum bandwidth of the equipment.

For details about anti-aliasing, check
https://www.allaboutcircuits.com/te...lters-applying-sampling-theory-to-adc-design/

 

tautech said:
"One needs understand many cheap DSO's offer very limited sensitivity in that as every measurement we take actually effect the value of the measurement value itself........."

rsjsouza said:
"Not only that, but in my experience several of these models lack an anti-aliasing filter......"


So then, what would be the lowest cost O-Scope to avoid these inaccuracies and perhaps other inaccuracies in measurement ?

Everyone can't just dish out the money for the best and most accurate oscilloscope. "Something is better than nothing"

Thanks

 

tautech said:
"One needs understand many cheap DSO's offer very limited sensitivity in that as every measurement we take actually effect the value of the measurement value itself........."

rsjsouza said:
"Not only that, but in my experience several of these models lack an anti-aliasing filter......"


So then, what would be the lowest cost O-Scope to avoid these inaccuracies and perhaps other inaccuracies in measurement ?

Everyone can't just dish out the money for the best and most accurate oscilloscope. "Something is better than nothing"

Thanks

There is a huge span between best and most accurate and a usable hobby scope for a few hundred. If you can't afford a decent upgrade to what you have now, then work, skimp and save until you have the money for something better.

 

There is a huge span between best and most accurate and a usable hobby scope for a few hundred. If you can't afford a decent upgrade to what you have now, then work, skimp and save until you have the money for something better.

then work, skimp and save until you have the money for something better.

So what scope (or class of scopes), by different manufacturers would be considered a significant upgrade worthy
of getting for semi-pro or pro accuracy ? ) "Pro" meaning that level of accuracy which would be beyond hobby level?

 

For an entry level oscilloscope, have a look at Owon, Rigol and Siglent, starting around $300.

 

tautech said:
"One needs understand many cheap DSO's offer very limited sensitivity in that as every measurement we take actually effect the value of the measurement value itself........."

rsjsouza said:
"Not only that, but in my experience several of these models lack an anti-aliasing filter......"


So then, what would be the lowest cost O-Scope to avoid these inaccuracies and perhaps other inaccuracies in measurement ?

Everyone can't just dish out the money for the best and most accurate oscilloscope. "Something is better than nothing"

Thanks

Many of the old CRO's offered adequate channel sensitivity but these aging instruments can themselve become repair projects and hold one back from advancing their hobby. < This for a while changed my advancement forever needing to fix equipment before being able to use it. After acquiring a reasonable DSO all these problems vanished and now I wouldn't touch a CRO with a barge pole.

Datasheets are your guide for product selection where max input sensitivity is always listed and ideally you should seek a DSO with 1mV/div or better sensitivity. We don't use these levels of sensitivity often especially in the digital world and most common need is to measure ripple on supply rails to ensure they meet manufacturer spec.
Next you need decide what BW instrument will meet your needs, now and as they grow.
IMO 50 MHz is the realistic minimum anyone should consider and preferably 100 MHz which can mostly suit the multitude of users needs.
Then comes the channel count, 1, 2 or 4 where if you are to do any protocol decoding 4 is the most preferred although 2 can suffice for the common protocols.
That now launches us into the feature set required where for the novice USB store and capture of screenshots can help us post screenshots online or to mentors when we seek assistance to understand an unusual waveform we don't understand.
Here the ability to also capture the scope settings used is of great benefit to anyone trying to analyze a screenshot and offer advice.
I could rattle on for hours but these basics are enough to point you in the right direct to maybe come back to us with findings to seek further advice on brands and your selection.
Happy hunting.

 

then work, skimp and save until you have the money for something better.

So what scope (or class of scopes), by different manufacturers would be considered a significant upgrade worthy
of getting for semi-pro or pro accuracy ? ) "Pro" meaning that level of accuracy which would be beyond hobby level?

I don't think you really don't need pro (the scope helps to earn your paycheck) accuracy, what you need is measurement usability (scope measurement specifications) for the job and reliability (in hardware,software and the user interface). $300 buys you that.

 

As a hobbyist, you may consider a $300 2-channel 100MHz Owon, Rigol or Siglent as your target must have dream oscilloscope.
In the meantime, there are lower priced (under $150) handhelds (e.g. Hantek 2C42) and tablets (e.g. Yeapook ADS1013D) worth looking at.

HANTEK 2C42


YEAPOOK ADS1013D



Consider DSO138 to be a toy.