I am the curator of my local church clock, an unusual example of a four face clock on a rural Essex church (most do not have a face pointing over the nave). The clock itself was installed when the tower was rebuilt in the mid 19th century, but as everything about the installation is cack-handed, I suspect the mechanism was not new at that time.
If anyone has ever played with a grandfather clock, the mechanism is broadly similar, but with every dimension scaled up about six fold.
It keeps reasonably good time, but the lever that trips the chiming mechanism is only consistent to about +/- ten seconds each hour.
This lever is lifted by a cam, first to prime the mechanism at about three minutes to the hour, and then initiate the chiming sequence on the hour itself. From initiation to actually ringing the bell takes about 3.5 seconds.
My idea is to run the clock very slightly slow, and then introduce a precisely timed actuator to nudge this lever so that it chimes precisely on time each hour.
The mechanics of making the actuator are not a huge challenge. I plan to use a small pneumatic ram, powered by a small 12V compressor of the type used to inflate car tyres. The compressor will need a few seconds to power up, so I plan to take a pulse from a timing device and use that to fire up both the compressor and a simple 555 based timer which will also fine tune the chime timing.
What I need therefore is a precise pulse to come in at 59 minutes and 50 seconds of each hour.
I've read up about the NPL 60KHz atomic time signal, but I note comments about it's unreliability and susceptibility to interference.
GPS seems more promising, but unless I've been looking in the wrong places, a module that can interface with an Arduino seems hard to find.
The Arduino technology I understand in principle, but have not played with in practice.
Can anyone point me to a device or module that can pick up the GPS time signal, and deliver it to an Arduino board in a manner that can be decoded?