Thanks Dragan. Interesting stuff... however, the digital scopes are still generating noise that contributes to the displayed waveform. How do we know whether it's the scope or the equipment under test that's generating the noise? Still, I'm glad expensive digital scopes have the same problem as my budget scope. I would have been miffed if I could have spent another $500 and not had that problem.
Probably a good start: literature.cdn.keysight.com/litweb/pdf/5989-3020EN.pdf On the other hand you could pretend that you are using a analogue scope and disable peak detect, engage BW limit etc ;) In reality most of that noise you are seeing with the digital scope was there with the analogue, you simply did not see it.
If it's below the BW limit and of sufficient amplitude. The "problem" with digital scopes is that you don't get the "noise masking" like with the analogue ones. For example: if you have some noisy switchmode power supplies or leds you can easily pick up the noise from those, with just the ground lead attached to the probe tip. There are a number of mitigation techniques (some are described in that document) that you can use.
Can you Try the new probes on the old scope?
Hi Adrian. Good idea, I'll try that.
About the noise on digital scopes, pretty nice video by Dave from eevblog: th-cam.com/video/Znwp0pK8Tzk/w-d-xo.html
Thanks Dragan. Interesting stuff... however, the digital scopes are still generating noise that contributes to the displayed waveform. How do we know whether it's the scope or the equipment under test that's generating the noise? Still, I'm glad expensive digital scopes have the same problem as my budget scope. I would have been miffed if I could have spent another $500 and not had that problem.
Probably a good start: literature.cdn.keysight.com/litweb/pdf/5989-3020EN.pdf
On the other hand you could pretend that you are using a analogue scope and disable peak detect, engage BW limit etc ;) In reality most of that noise you are seeing with the digital scope was there with the analogue, you simply did not see it.
Thanks Dragan, I'll take a look at it. If I do all that will I still see any real noise on the signal I'm looking at.
If it's below the BW limit and of sufficient amplitude. The "problem" with digital scopes is that you don't get the "noise masking" like with the analogue ones. For example: if you have some noisy switchmode power supplies or leds you can easily pick up the noise from those, with just the ground lead attached to the probe tip. There are a number of mitigation techniques (some are described in that document) that you can use.