Thursday, 23 January 2014


Some years ago I looked for a simple clock to have an accurate time available in my shack.
I found a nice design on this website:  => Projecten => Digitale DCF77 klok

Circuit diagram DCF77 clock

I built the simple version (without sound) at the time and the clock is still working fine.
The clock uses a 16F628 PIC and a DCF77-module.
I selected a nice blue display to present the time.

                                                 DCF77 receive module

The longterm accuracy of the DCF clock is ok for normal use: After one year the deviation of the second is no more than +5 to +150 msec.

 Clock in operation

All about the 77.5 KHz  DCF77 transmitter in Mainflingen:


  1. Prachtig, en het kan nog kleiner. Heb zo een ontvanger/klok in m'n horloge zitten. Ding heeft zelfs een S-meter!
    Zie: The Ultimate HAMradio wristwatch
    73, Bas

  2. Ja dat is zeker leuk speelgoed Bas. Mooie wristwatch. Toch knap dat je langegolf signalen met zo'n kleine antenne in een horloge kunt ontvangen...