I found an old photo of a physics experiment I did in highschool back in 1979. It shows a Lissajous curve. A lightbulb on a string draws the lines of the curve on a film in an analogue camera set to high exposure time. Black/white only since I developped the picture in the old-fashioned way (with patterson development tank and fluids; no smartphones with Megpixels available at that time).
During last visit of the PI4RAZ club meeting there was some used equipment for sale. I found a nice Philips N8402 dynamic stereo microphone. I hope to use this mike for the ATV video transmitter under construction. More tech info about this microphone (designed around 1970): http://www.radiomuseum.org/r/philips_n8402n_840.html