When will doctor who new season release?

I  don't know answer of this question but it seems we don't wait too much time. I think it will be released in May 2012. Who knows what kind of adventures wait us new season...

Simple Flip-Flop Circuit

We can start with simple flip-flop circuit. This circuit most important point is base capacitor and resistor values. If these values have not appropriate values, your circuit leds are not blink. This thing interested in capacitor charge and discharge time. As you now capacitor charge and discharge time 5T. T is equal to R multiply by C. You can download schematic this circuit. I used proteus.

Link: https://rapidshare.com/files/645793453/simpleflipflop.DSN