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Bandwidth.
Most ADC's can give you 80 khz analog bandwidth. Scopes can give more, but is it really needed? I suppose it would be for good squarewaves much above 1 khz.
Bandwidth.
Yes, if you want to adjust the circuit to minimize ringing and risetime. A meg is not too much, which is why I use an analog scope for this. Likewise, with a 10x probe, you won’t perturb the measurement too much.Most ADC's can give you 80 khz analog bandwidth. Scopes can give more, but is it really needed? I suppose it would be for good squarewaves much above 1 khz.
I'm of course aware of some of what you've been doing. I will ask more specifically, how would you use the O-scope to tell you something you can't find out with software and an ADC? Or what functions would an o-scope give that software and an ADC can't?
If it can be done adequately via software, I'm not sure how to do it and what gear I would need.
Possible but not cheap. OTOH, you can buy a perfectly adequate used scope off eBay for like $100 or so.
checking for oscillations for instance is something audio analyzers can't do.
Granted you need quite a few MHz bandwidth for that.
Like audio analyzers O-scopes have their place.
Have a good scope at work and Handyscope at home.
I would be using it for analog purposes (vinyl, RTR).
How much does the bit limit matter that case?
If you want to check an analog amplifier, then a scope is really good, but if you have a vinyl test (with sinewaves recorded) I really think a second hand ASUS U7 (mkI, not mkII) could do the job very well with RMAA, ARTA and REW.
If you want to check an analog amplifier, then a scope is really good, but if you have a vinyl test (with sinewaves recorded) I really think a second hand ASUS U7 (mkI, not mkII) could do the job very well with RMAA, ARTA and REW.
"DS1000Z built-in signal source can output a variety of basic waveforms, including sine, square, ramp, pulse, DC and noise" - source: http://beyondmeasure.rigoltech.com/acton/attachment/1579/f-050a/1/-/-/-/-/MSO1000Z&DS1000Z_UserGuide.pdf
You will not be able to do a proper FFT with such a scope, mostly because of a less than 16-bit internal resolution, but also because the signal generator's THD+N is usually higher than DUT's native THD+N.
I personally find a scope very useful to see if there's frequency roll-off or if there's post-ringing or pre-ringing, especially with speakers/headphones connected.
Okay, looking at the docs, I see a couple of concerns. For the signal generator:
"Set the amplitude Press Amplitude to set the amplitude of the signal. For the setting method, please refer to the introduction in "Parameter Setting Method". When the impedance is set to HighZ, the range is from 20 mVpp to 5 Vpp; when the impedance is set to 50 Ω, the range is from 10 mVpp to 2.5 Vpp."
So if I'm going to use this to push square waves into a step up transformer designed to take inputs in the <1mV range (specifically, .30mV, i.e. 1/30th of what is listed above), is that going to screw things up, either in the measurement arena or actually damage the transformer?
Maybe @SIY knows...
Take a look at the test setup I recommended in this article. And come at me with any questions. Basically, you set up a voltage divider having the same source impedance as the cartridge, and that will knock down the voltage to reasonable levels.
You can replace the lower 30k resistor with a short if you're running unbalanced (which 99.9% of vinyl setups are). Then the shunt resistor would be 10R to match the source resistance of the cartridge, since the 30k resistor is so large in comparison. The attenuation is 20 log(10/(10+30k)) = -70dB more or less. So drive this with a volt or so and your transformer will only see 0.4mV or so.