Gents GPO master clock 30 seconds impulse debouncer.
By adding this circuit into the drive circuit of the GPO, the occasional double bouncing of the contacts can be avoided. It also improves the accuracy of the GPO's timekeeping.
The 220 mA slave dial current has been taken away from the clock contacts. When these get older and a bit worn, the bouncing problems start gradually appearing.
The latter switches now only the base current to the BD647 or eq. transistor.
Time constant is set by a capacitor.

In the second part of the video I have used the same circuit to drive a synchroniser to keep an other pendulum clock in synch. This can be duplicated for more clocks, and I will add an other video to show the set up, when I have wired it all up in my spare time.
On the second circuit I made the timeconstant shorter (1/2 to 3/4 sec) to have the perfect pulse duration to keep the pendulum in synch.

Dependant upon the weight of the other slave pendulum a longer or shorter impulse may be required.
This can easily be changed by changing the capacitor or the bleed resistor to a different value.
I forgot to add the schematic to this video. Just drop me an email and I will sent it to you.

17 Oct 09. I have synched two more Bürk master clocks from this set up. basically these 3 similar Bürk clocks all run off the same relay and run in perfect synchronisation with the Gents GPO. (less info)