because it gets in resonance with its own balance, a significant deviation occurs.
The resonance takes energy from the balance and the balance looses amplitude, the root cause for the deviation.
Some photos show the oscillating watches, just aprox. 2 mm, but that can cause a deviation of about plus TWO minutes per day.
An interesting technical effect, at least for me.
I have checked it with a ref. 5301 and with a cal. 67 from the 40s.
The C.67 commutes more intensive as the ref. 5301, a matter of better resonance, due to weight of case and movement.
And I am sure there will be many other PW models.
Every owner of those watches in steel can do this test, just hanging it on a fixed hook.
The photos should show the intensity of the commute, with an exposure time of > 2 seconds each.
Some pocket watch holders have hooks and I am sure, some pocket watches will have the same problem on those items.
BTW, I have got the hint to this pendulum effect from a Swiss collector, who was wondering about the accuracy deviation of his 5301 on a pocket watch holder with a hook.
The ref. 5301 has a very good accuracy on a stand pocket watch holder. So, I used this one to check the deviation on the hook.
It is aprox. plus 4 seconds per hour.
Regards
HEBE
