mm0fmf wrote:
On 06/08/2017 19:16, Brian Reay wrote:
On 06/08/2017 19:15, Gareth's Downstairs Computer wrote:
On 06/08/2017 18:52, rickman wrote:
Gareth's Downstairs Computer wrote on 8/6/2017 1:37 PM:
On 06/08/2017 17:18, rickman wrote:
Gareth's Downstairs Computer wrote on 8/6/2017 5:26 AM:
On 05/08/2017 23:25, rickman wrote:
You seem to be completely misunderstanding the operation of the
Shortt
clock. The slave pendulum has no need for correction of circular
error.

I'm sorry, but you totally misunderstood what I was saying, which was
that because all pendulums exhibit circular error, when the hit
occurs
in the hit and miss synchroniser and foreshortens the swing, then,
for
that half-cycle, and only that half cycle, the frequency is
changed, as it must be.

Just as in the electronic PLL, instantaneous changes of phase have
instantaneous changes of frequency, no matter how short lived,
associated with them.

What you say about frequency vs. phase is true and how the Shortt
clock
adjusts phase, but it has nothing to do with circular error of the
pendulum. The correction of the phase is from the added spring
resistance
shortening the time as well as the travel of the pendulum. The fact
that
the swing is shorter and the second order circular error will create a
tiny error in the timing is pretty much irrelevant. The real
change is
from the added spring constant changing the first order effect in the
pendulum equation. The coefficient of the gravitational constant is
effectively changed by the spring.

Is that more clear?


You continue to misunderstand. Any pendulum swinging with circular
error
speeds up for shorter amplitude; speeding up means increased frequency.
Therefore, for the half cycle inwhich there is a hit, a shorter
amplitude
and hence instantaneous higher frequency exists.

I understand perfectly and explained it for you in excruciating
detail. The change in phase of the Shortt clock slave pendulum is due
to the FIRST ORDER change in the effective gravitational constant in
the pendulum equation by engaging the leaf spring. While the reduced
amplitude of the swing *will* cause a SECOND ORDER effect in the
motion of the pendulum, it will be MUCH SMALLER than the FIRST ORDER
effect.

What part of this do you not understand or not agree with?


It's not that I do not understand nor disagree with you, it's that
you're off on a complete tangent to what I was suggesting, and
do not realise it.



No he isn't, you are not keeping up.

If he's not keeping up then he needs Viagra.


I expect that Mrs Evans has been putting bromide in his tea since shortly
after they got married.

--
STC / M0TEY /
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