Have an oscilloscope lying around?

[Brax]

http://www.engadget.com/2007/12/07/oscilloscope-turned-into-star-wars-playing-mame-machine/

Play vector games on it!

[ahofle]

Also mentioned a few posts down:
http://forum.arcadecontrols.com/index.php?topic=74240.0

 

[SavannahLion]

Sadly, this won't work on all oscilloscopes. I dropped by Fry's not too long ago and swung by their oscilloscope section. To my surprise, every single one of them were using raster CRT's (possibly LCD's too) and not vectors. After fiddling with them a bit, I realized these were digital oscilloscopes with full graphic interfaces.

And the jaggies on the two or three properly set up for display were phenomenally bad. I can't believe anyone is willing to spend $1,000+ for this modern piece of ---steaming pile of meadow muffin--- when an old school model using a vector CRT were much more pleasing to look at.

[MonMotha]

The high end digital scopes offer many, many features which make them infintely more useful as scopes than the old analog models.  Now, if you want to use it as a vector monitor, yeah, find an old analog scope, but for using it as an actual oscilloscope digital storage, colored traces, non-causal triggers, simultaneous sampling, trigger on pattern, sample and hold/display, untriggered rolls, etc. are all very, very useful features that cannot be done on analog vector screens.  Digital scopes also offer options to load things like templates for eye diagrams, export either screen captures or the raw V vs. t data, save settings, remote control via serial, USB, or GPIB, and many even offer FFT features which can sometimes remove the need for a spectrum analyzer (a very expensive piece of equipment) on some projects.

If you were seeing jagged edges on the traces, you were either right at the edge in terms of sampling capabilities and/or the scope didn't oversample sufficiently.

If you're only spending $1000 or so on a scope, you're getting a fairly low end scope.  Good digital scopes tend to be in the $2500 range for a 100-250MHz model, depending on features.  If you want a multi Gs/sec model with a couple GHz analog bandwidth, you're looking at dropping $25k or more on the instrument.

I have an old-school analog scope for my projects, and I have to say that 95%+ of the time, I'd prefer a modern digital scope like I have at work.  I just can't justify buying one for my little hobby projects.

Many of the digital scopes do still support XY mode, though not all offer a Z-axis input anymore.  They don't actually draw it on a vector screen, but they will still display X vs. Y voltage channels.  It's useful sometimes.  The option is usually either in the trigger menu or the extreme setting on the horizontal dial.  There may be a little lag, but it's likely to be imperceptible.  Trace persistence is a settable parameter, usually.