A 4 digit LED clock built with an Arduino Uno and an inexpensive ublox NEO-6M GPS module GY-GPS6MV1 to set the time automatically and keep it in sync.
The GPS module has a battery to keep its Realtime clock running even if the GPS signal is lost.
The 4 digit, 7 segment LED display is common cathode, type number 5461AS.
The clock will automatically change to and from Daylight Saving Time for the timezone chosen.
The time can also be toggled to and from UTC and local time, by using an infrared remote controller.
Most components needed are in the Sainsmart UNO R3 Starter Kit: http://www.sainsmart.com/starter-kits/uno-r3-smartkits/sainsmart-uno-r3-starter-kit-with-16-basic-arduino-projects.html
Ublox NEO-6M GPS Module GY-GPS6MV1 Aircraft Flight Controller For Arduino is available from eBay for about £15.
