Go to Oscilloscope Videos (EEVBlog videos by Dave Jones that are tagged with "oscilloscope")
The best videos are the oscilloscope reviews. Unfortunately, some of them do not contain the "oscilloscope" tag, so I list them here separately: A review of a second hand 50 MHz analog Tektronix scope 2225 (33 minutes), of the Tektronix Mixed Domain Oscilloscope MDO4000 (1 hour 27 minutes), the Agilent Infiniivision 2000 X Series (1 hour 2 minutes), the Agilent Infiniivision 3000 X Series (25 minutes, it builds on the 2000 X video, so you should watch that video first), a firmware upgrade of the 3000 X (19 minutes) a short discussion of the High Res mode of the 3000 X and a review of the popular Rigol DS1052E (5 minutes).
If you want to get an idea about the current price of these scopes, please take at look at the advert at the bottom of this page. I have shown there the oscilloscopes from the reviews above (except for the second hand Tek) and also some others from the Agilent 2000 / 3000 X series (among them the MSOX 2024A and the MSOX 3054A Mixed Signal Oscilloscopes that are shown in the videos). After you have recovered from the shock, take a closer look at the Rigol DS1052E. Or listen to Dave's plea for the analog scope. With some experience and a little luck you can find really nice and affordable second hand analog scopes.
Dave is quite famous for his reviews. Not only of scopes, but also other electronics measurement equipment - very nice is the Multimeter Shootout Part 1 and Part 2. Here is a complete list of all his videos (please scroll down a bit to see the list). Many of the big manufacturers let him "play" with their brand new products, so following his videos is a good way to keep informed about the latest developments. There are also some videos with long interviews where representatives at trade shows talk about their product lines or demonstrate the features of their latest scope to him. But this kind of marketing talk is much less interesting than his own reviews.
The videos also contain a good tutorial about DSOs in general and a more advanced one about trigger holdoff (if you prefer written tutorials, take a look at XYZs of Oscilloscopes for digital scopes and the Oscilloscope Applications Guidebook for analog scopes). There are also several "Oscilloscope Teardowns" where Dave opens the oscilloscopes and takes a close look at how they are built. This is quite interesting if you already have a good knowledge of practical electronics. But the beginner who is seeking for basic information about scopes can probably not learn very much from this.
You may also be interested in some other Recommendations for Introductions to Oscilloscopes.
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