LED Running Display Using NE555

Here's a circuit to build a led based running display using easily available general purpose timer IC NE555 and a popular decade counter IC CD4017. This display consist of 24 LED's of four layers. The NE555 is wired as an astable multivibrator whose output triggers CD4017 counter.

LED Based Automatic Emergency Light

Here is a white LED based low cost emergency light that offers high brightness, automatic activation, automatic charging with the use of cheap components. The circuit is very simple in construction and we can use the emergency light up to  6++ hours on battery feed.