Mike Logix: I tried this with my digital scope. It does not quite look the same, you can almost see the samples broken up. If I increase the persistence of the display I can view a lissajous pattern if the frequencies are the same, but if I shift the frequency of one channel then the pattern becomes unrecognizable. Great presentation.
BitemyShiny MetalAss: i think i owe you a beer (or two..cases of) . you've got good content.
Stillpoint X: Great explanation!!!
Emiliano Caballero Fraccaroli: Great video, thanks!
mfbbfm: top video. Thanks a lot
nzoomed: I was hoping i could do this on my Tektronix 561A scope, but the 3B3 timebase has no Horizontal input! Yet some cheaper really basic kitset scopes that are far older are capable of doing this! I have such a scope, but it power transformer needs rewinding!
David Newman: Audiobulb has a Lissajous standalone software package and a Max for Live - Ableton version. Bringing sound and visual and outputs all together.
Peter W. Meek: A favorite pastime - experimenting with lissajous patterns.
My father had a polar oscilloscope - a set of secondary deflection "plates" were a center pin (right in the middle of the screen) and a ring around the edge of the circular CRT. The input signal would move the trace towards and away from the center pin. The basic trace was (of course) a lissajous pattern made by a set of 90˚ out-of-phase sine waves on the normal XY deflection plates. I didn't see it among his things, so I suppose something terminal happened to it (maybe the irreplaceable polar CRT died) and it was disposed of.
I expect such a display could be synthesized by running the polar input signal into a pair of multipliers - one multiplying the polar input signal with a 0˚-phase X drive-signal and the other multiplying it with a 90˚ phase Y. The outputs of the multipliers would be fed to the X and Y inputs. If my "thought experiment" is right, this should create a circular trace which changes by getting closer to or further from the invisible center by the amount of the polar input.
(I leave trace speed and sync as an exercise for the reader.)
Evan Wolfe: Very Cool Video. My instructor in school pointed me towards looking into what happens when 2 waveforms of close frequency are plotted on the xy axis on an oscilloscope. Your video helped explain the o-scope display. Thanks. Just another ham operator here...Keep It "ReeL",Evan Wolfe
Ivo Wilson: Great video, very informative, and nice equipment!
Asit Tarsode: thanks a lot
Yash Shah: Hey! I just have a very simple question. We use the Lissajous pattern to essentially measure an unknown frequency connected at the other channel on the CRO. However considering this aim, we can easily connect a signal with the unknown frequency and directly measure the time from the visual and find out its frequency. Why connect two channels and study these patterns!?? Please reply!!
Crux: absolutely mindblowing, thank you! :D
Dustin Hunter: This was a very good explanation of Lissajous patterns. As a college student in a physical chemistry class, this helped quite a bit.
James Haskin: Very cool overview. Thanks!
Multirotor Fun: Excellent. Would have loved to see the stereo music thing you mentioned.
Kalkaekie: Very interesting !
#48: Basics of Lissajous Patterns on an Oscilloscope5
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