Go Down

Topic: Should a serious hobbiest/EE own both a digital and and an analog oscilloscope? (Read 662 times) previous topic - next topic

DVDdoug

I don't own a 'scope, but sometimes I lust for one!  :D

I've rarely needed one (for analog or digital stuff), and since I work in electronics I can bring my hobby projects into work on the weekend.

We don't have any analog 'scopes at work anymore.    As far as I know, there is no advantage to an analog 'scope as long as they both have the same speed (MHz).    The Tektronix digital 'scope on my bench right now is rated at 100MHz, with a sample rate of 1.25GS/s. 

Analog waveforms look perfectly "smooth and analog".  The measurement features are a nice bonus...  It measures period/time, frequency, and voltage (and maybe some other stuff I don't use).  Another nice thing with a digital scope is that you get a "nice picture" no matter what you are looking at.   For example, when you look at a very low-frequency waveform (let's say 1Hz) on an analog 'scope you don't get a waveform, you see a dot tracing across the screen.  If the frequency is a little higher, you'll get a waveform, but it will flicker.    Or, if you're looking at a short pulse with a low repetition rate, it can be very-dim.  On the digital 'scope you can always see the pulse, and I never even touch the brightness control.

It might be like the analog audio myths…  A lot of audiophiles seem to think that analog vinyl has “infinite” resolution.    That’s nonsense, since the noise floor makes the resolution/accuracy far worse than a CD.   It’s OK to prefer analog sound if that’s what you like, but digital is technically superior.   Or, it’s like saying that my “analog” ruler is better than my digital calipers.

One “interesting” thing is that the screen resolution on my Tektronix ‘scope is “only” 8-bits.   That seems terrible, but that’s 256 “dots” which is about half that of DVD.  I'm pretty sure you can't see a 1-bit change on a 4-inch screen. 

Osgeld

I have both, neither one very serious, but they are extremely handy. I use the scope way more than the LA, and the only time it really comes out is when I need to debug a stream of data.

Quote
You don't get both with any instrument.


You can, my scope is a Kenwood DSO from 1987, its only 20Mhz, but its a CRT based machine with both analog and digital storage functionality, and its very rare that I switch it over into analog mode. Last time I did I was looking at a 28.something Mhz crystal and the DSO couldnt latch onto the very short peeks 8Mhz past its bandwidth (but the analog function showed it).

Fully digital seems to be king, cause its cheap, and today its pretty damn fast, there is always a hint of lag, but there is so much memory available and features in modern models, it more than makes up for it.


dhenry

You cannot be a serious EE if you have to have both digital / analog scopes.

Osgeld

humbug, even in our LAB at work, sitting next to the tens of thousands of dollars Tektronix with its dual LCD's we keep the old analog only scope around ...why?

its for when the noobie starts getting mouthy so we can threaten him with it

Grumpy_Mike

Quote
You cannot be a serious EE if you have to have both digital / analog scopes.

More rubbish from dear Henry.

There are expensive digital scopes with digital phosphors but they don't work in all situations.
The main use of an analogue scope is looking at a modulated signal on a HF carrier, try that on even the best digital scoopes.

Go Up