X/Y scope mode [was]Re: [sdiy] Hamfest

[Byron G. Jacquot]

>> If you don't have an oscilloscope, pick one up.  You'll be able to get a lot
>> of use out of a 2 channel, 20 MHz scope for audio work.  Try for one with an
>> X/Y mode, which is handy for some audio problems, as well.

>    X/Y mode is also good for checking the transfer function of circuits.  When
>I am working with the DIODE shapers, I feed a triangle into the input, and clip
>the X prob onto the input, and the Y probe onto the output.  You get a nice
>display of the input versus output.

I like to use it for setting the reproduce head azimuth (the tilt of the
head relative to the direction of tape movement) on analog multitracks.
Much easier to tell the difference between a straight line and an ellipse,
than try to line up a pair of sinewaves!

I also seem to recall a method for calibrating VCOs using Lissajous figures,
but I've never tried it myself.

Byron Jacquot