DCF-77 PIC LED clock | Microcontrollers Project

1. What is DCF77 ?

DCF77 is the name of a german radio station on 77.5 KHz, which gives official time and date from an atomic clock located in Francfort. The time and date is coded into a 59 bit length frame, and is sent on the air through an antenna, by a 50 kilowatt power amplifier.
A simple and tiny receiver can catch the signal, from approximately 2000 kilometers around the antenna. The pulse contained in the radio frequency signal is filtered by the receiver : a 100 ms pulse is a value of 0, a 200 ms pulse is a value of 1, there is a pulse per second, and the last second of a minute lacks (there is 2 seconds without pulse) to allow synchronisation with the next minute.
There are many good web sites about DCF77, I strongly recommend to visit the official DCF77 web site :
it contains all that you have to know about DCF-77. You can also try a Google search on DCF77 and select the most appropriate result for your convenience.