(Exact Pendulum Beacon)


Transmiting schedule(Edit)

Beacon transmiting dots every seconds, without transmiting call, foF2 index and time number. In full minute transmit dash after three dots.

foF2 source


Pendulum is enclosed in a vacuum chamber (by www.vakuum.cz) to avoid the impact of changes in atmospheric pressure. Infra red sensor detected position of pendulum. Software measured and evaluated gearing a la Froment electrics system

System status(Edit)

Phase (deviation pendulum running within one second).

Link detailed status

Earthquake 14. Aug 2012(Edit)

in sea of Okhotsk (49.784°N, 145.126°E) with [magnitude 7,7 http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/usc000bz29.php]

Seismogram from Prague

Pendulum deviation

Dependence frequency error on air pressure(Edit)

between 15 and 21 Dec 2011

Results of G3PLX measurement at 12/13 Dec 2011(Edit)

Here attached is a good record from last night. The channel was clear of the Sura ionospheric radar which has been there for a week or so. This shows two shift pulse events, with the pendulum running about +3ppm between them. The 60mS point on my graph is the same point as the 0 mS point on your Phase graph. The 60mS difference is made from (1) 50mS because you measure the start of the dot and I measure the centre, (2) 4mS because I am 1200km from Prague, and (3) 6mS which we think may be the key-click filter in your transmitter.

Squadron of pendulum(Edit)

  • Frantisek OK1DF - Founder and the mastermind
  • Petr ex OK1IRG - Software developer
  • Jan OK2ZAW - Beacon hardware
  • Peter G3PLX - Invaluable assistance
  • Dan OK1HRA - It & webmaster