I built the saw-tooth oscillator out of a 555. It can be done, contrary to what I said in a previous post. The trick is to supply a regulated current to the timing capacitor, which creates a linear ramp. This is done simply with a single transistor configured as a current source. Unfortunately you also have to isolate the output with a high impedance buffer. For the experiment I used a little Radioshack amplified speaker, shown in the video, which seems to have a very high input impedance as it didn’t effect the frequency of the oscillator at all. For a stand alone design an op-amp buffer stage would be required. So it’s a toss up as to whether this design is any simpler than the one I posted earlier which uses two op amps and a JFET.