The pendulum's rod and bob
with IR sensor
OK0EPB - 7 039,4 kHz
(Exact Pendulum Beacon)
The Czech time radiobeacon driven by pendulum
The clock's machine works on the basis of Froment's system with a constant impulse. (take a look here)
The maximum difference of time signal is held in the tolerance of 0.1 sec.
The output power of TX is 1 (one) W to dipole @22m.
ok0epb@ok0epb.cz
System status
a la Froment electrics system |
Pendulum in time-cellar |
OK1DF & beacon |
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IR sensor |
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Dependence frequency error on air pressure between 15 and 21 Dec 2011
Results of G3PLX measurement at 12/13 Dec 2011
| 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. |
Our phase diagram to compare
