Simple LED Bike Light Schematic

We know flashing LED lights from the high street shop. But, they were often gave me trouble with flat batteries and lights that fell off. In this case, we make a better one idea using another front wheel, one which has a dynamo already built in the hub. This supplied a nice sine wave of 30 Vpp (at no load). With this knowledge I designed a simple power supply. The transistors that are used are type BD911. These are a bit of an overkill, but there were plenty of these at my school, so that is why I used them. Something a little smaller will also work. The power supply is connected to an astable multi-vibrator. This alternately drives the front light and the rear light. This is the figure of the circuit.