SG90 servo position depends on 1ms (one millisecond) to 2ms high pulses that are spaced approx. 20ms apart. 555 timers wired in astable mode easily produce low outputs for a lot longer time than high outputs. One of the best selling set of servos on Amazon. Clicking on an Amazon affiliate link before making any … Continue reading "Servo controlled with LDR and 555 timer circuit"