A near 50% duty cycle transistor oscillator! Frequency is variable by altering the values of a single RC network. And if you want, you can change the duty cycle by altering the 2 thresholds. Overall, fairly simple and stable; but is limited to only lower frequencies... probably because of the latching component in the circuit, not so much the propagational delay. However I think It's a very nice little oscillator that wouldn't be to difficult to build if you want a neat little square wave generator to add to your work bench that has an adjustable frequency and a 50% duty cycle capability.
