haha no im not trying to scare off animal, im trying to build a walking stick for the blind that has a sensor on it, so when the stick approaches an object thats close it will generate a sound through an amplifier. i am aware that the guide dog might be annoyed with it and go insane.
sorry for not specificing the stability of the frequency. the the frequency range is -+5% of the 40khz, so thats 38KHZ< X < 40KHZ. i have thought of using electrolytic, but i was told by someone that it would not do the job at all
i have another question though, would this oscillator drift? as in its not very stable with the 555?