> Point a video camera at the screen, tape it and freeze frame
> the result?
>
> This will only work if the waveform occurs while the CCD is
> capturing the image
>
> Bob Ammerman

That works fine - sometimes you need a couple of goes to
get a good one. Turn the brightness way down BTW

(sorry Mr Dilatush)

http://home.clear.net.nz/pages/joecolquitt/davedong.html

Upper picture is a quick tone-burst happened to have been
caught mid-screen. Note the older persistent trace vs the
more recently drawn (night - room lit)

Lower picture is a standing wave, easy, although both traces
were very faint to the naked eye (daylight)

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