A mechanical phase locked loop!
 

Gareth's Downstairs Computer wrote on 8/5/2017 5:57 PM:
On 05/08/2017 22:24, rickman wrote:
Gareth's Downstairs Computer wrote on 8/5/2017 3:14 PM:
On 05/08/2017 20:06, rickman wrote:

Yes, because it *is* a PLL. In fact the problem most people have with it
is that it doesn't adjust the phase by adjusting the frequency of the
slave. It adjusts the *phase* so clearly it *is* a phase locked loop.

All pendulums have circular error where the frequency is determined by
the amplitude of swing,

All *uncorrected* pendulums have circular error. The Fedchenko clock has
a mounting spring for the pendulum that corrects for circular error.

Hadn't heard of that one. At the BHI lecture there was mention of
another correction of circular error by a colied spring attached
somewhere at the bottom, but I wasn't paying full attention at
that point.

There were also other means such as cycloidal cheeks around the
suspension spring.

so for the half cycle where the phase is adjusted by
abridging the swing by the hit of the hit and miss stabiliser, the frequency
of the slave is, indeed, changed.

This has nothing to do with the circular error.

It has everything to do with the circular error and the variation
in frequency that comes with varying amplitude of the swing.

You seem to be completely misunderstanding the operation of the Shortt
clock. The slave pendulum has no need for correction of circular error. It
is a good pendulum, but not a great one. It doesn't need to be great, it is
corrected every 30 seconds by the electromechanical escapement of the master
pendulum. It only has to be good enough to provide an appropriately timed
release of the gravity lever.

So the small circular error has no bearing on the slave pendulum.


The standard formula given for the cycle time of pendulums ..

2 * PI * root( L / G)

... is only valid for those small angles where sin( theta ) = theta,
and such angles are so infinitesimal that no visible movement
of a pendulum would be seen!

This equation is an approximation which ignores the higher terms of the
power series of the full equation. It is only truly valid for no swing at
all.

... which is virtually the range where sin( theta) = theta.

Exactly. This *is* the range where sin(theta) = theta. Anywhere other than
zero it is an approximation.

--

Rick C

A mechanical phase locked loop!
 

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.

A mechanical phase locked loop!
 

On 08/06/17 10:38, Jeff wrote:

You are making pointless distinctions. A phase locked loop is not
defined by its mechanics but by the nature of its control. The Shortt
clock maintains the relative *phase* of the two clocks by brief
adjustments to the frequency via a spring. This is controlled by
measuring the relative *phase* of the two clocks.


Wrong! It does NOT measure the relative phase, it makes NO measurement
of the phase difference. All it does is detect if there is a phase lag
of any degree. It could be a fraction of a degree or 180 degrees, the
same correction is then applied regardless.

It's that simple. You are just making things more complicated by
talking about the details of how the adjustment works and the time
function of the frequency. NO PLL can keep the two clocks perfectly in
sync.

Calling it open loop is just absurd. The loop is closed because it
*measures* the phase of the clocks and adjusts the phase according to
the measurement. It may be binary, but the adjustment is controlled by
the measurement.

Wrong again it is open loop, there is no measurement, just the same
adjustment regardless of the phase difference.

Jeff



Might be easier to define a set entitled "Locked Oscillators, of which
the phase locked loop, injection locked and hit and miss synchronised
are all members.

Are there other candidates ?...

Chris

A mechanical phase locked loop!
 

On 06/08/2017 12:24, Chris wrote:
On 08/06/17 10:38, Jeff wrote:

You are making pointless distinctions. A phase locked loop is not
defined by its mechanics but by the nature of its control. The Shortt
clock maintains the relative *phase* of the two clocks by brief
adjustments to the frequency via a spring. This is controlled by
measuring the relative *phase* of the two clocks.


Wrong! It does NOT measure the relative phase, it makes NO measurement
of the phase difference. All it does is detect if there is a phase lag
of any degree. It could be a fraction of a degree or 180 degrees, the
same correction is then applied regardless.

It's that simple. You are just making things more complicated by
talking about the details of how the adjustment works and the time
function of the frequency. NO PLL can keep the two clocks perfectly in
sync.

Calling it open loop is just absurd. The loop is closed because it
*measures* the phase of the clocks and adjusts the phase according to
the measurement. It may be binary, but the adjustment is controlled by
the measurement.

Wrong again it is open loop, there is no measurement, just the same
adjustment regardless of the phase difference.

Jeff



Might be easier to define a set entitled "Locked Oscillators, of which
the phase locked loop, injection locked and hit and miss synchronised
are all members.

Are there other candidates ?...

From pre-war, the Goyder Lock?

Which raises an interesting point; before the 3-tier
coffer-filling fiasco was the spawn of the RSCB, the candidature
for the RAE tended to know all about the history of amateur radio
before getting their licence, but now they seem to know
sweet FA even after getting their licences, such as the
difference between sideband and sidetone.

A mechanical phase locked loop!
 

On 06/08/2017 13:52, Gareth's Downstairs Computer wrote:
On 06/08/2017 12:24, Chris wrote:
On 08/06/17 10:38, Jeff wrote:

You are making pointless distinctions. A phase locked loop is not
defined by its mechanics but by the nature of its control. The Shortt
clock maintains the relative *phase* of the two clocks by brief
adjustments to the frequency via a spring. This is controlled by
measuring the relative *phase* of the two clocks.


Wrong! It does NOT measure the relative phase, it makes NO measurement
of the phase difference. All it does is detect if there is a phase lag
of any degree. It could be a fraction of a degree or 180 degrees, the
same correction is then applied regardless.

It's that simple. You are just making things more complicated by
talking about the details of how the adjustment works and the time
function of the frequency. NO PLL can keep the two clocks perfectly in
sync.

Calling it open loop is just absurd. The loop is closed because it
*measures* the phase of the clocks and adjusts the phase according to
the measurement. It may be binary, but the adjustment is controlled by
the measurement.

Wrong again it is open loop, there is no measurement, just the same
adjustment regardless of the phase difference.

Jeff



Might be easier to define a set entitled "Locked Oscillators, of which
the phase locked loop, injection locked and hit and miss synchronised
are all members.

Are there other candidates ?...

From pre-war, the Goyder Lock?

Which raises an interesting point; before the 3-tier
coffer-filling fiasco was the spawn of the RSCB, the candidature
for the RAE tended to know all about the history of amateur radio
before getting their licence, but now they seem to know
sweet FA even after getting their licences, such as the
difference between sideband and sidetone.




House!

A mechanical phase locked loop!
 

On 08/06/17 12:52, Gareth's Downstairs Computer wrote:
On 06/08/2017 12:24, Chris wrote:
On 08/06/17 10:38, Jeff wrote:

You are making pointless distinctions. A phase locked loop is not
defined by its mechanics but by the nature of its control. The Shortt
clock maintains the relative *phase* of the two clocks by brief
adjustments to the frequency via a spring. This is controlled by
measuring the relative *phase* of the two clocks.


Wrong! It does NOT measure the relative phase, it makes NO measurement
of the phase difference. All it does is detect if there is a phase lag
of any degree. It could be a fraction of a degree or 180 degrees, the
same correction is then applied regardless.

It's that simple. You are just making things more complicated by
talking about the details of how the adjustment works and the time
function of the frequency. NO PLL can keep the two clocks perfectly in
sync.

Calling it open loop is just absurd. The loop is closed because it
*measures* the phase of the clocks and adjusts the phase according to
the measurement. It may be binary, but the adjustment is controlled by
the measurement.

Wrong again it is open loop, there is no measurement, just the same
adjustment regardless of the phase difference.

Jeff



Might be easier to define a set entitled "Locked Oscillators, of which
the phase locked loop, injection locked and hit and miss synchronised
are all members.

Are there other candidates ?...

From pre-war, the Goyder Lock?

Which raises an interesting point; before the 3-tier
coffer-filling fiasco was the spawn of the RSCB, the candidature
for the RAE tended to know all about the history of amateur radio
before getting their licence, but now they seem to know
sweet FA even after getting their licences, such as the
difference between sideband and sidetone.




Hadn't heard of that, so looked it up and found:

http://www.dxmaps.com/discuss/oven.html

Which was an interesting read, but not enlightening.

Some of the early scope timebases, puckle, for example sounded
interesting, but they were effectively injection lock, of course.
I guess a triggered timebase is a variation of the hit and miss model.

Couldn't grok the relevance of the following paragraph above :-)...

Chris

A mechanical phase locked loop!
 

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?

--

Rick C

A mechanical phase locked loop!
 

Jeff wrote on 8/6/2017 6:38 AM:

You are making pointless distinctions. A phase locked loop is not defined
by its mechanics but by the nature of its control. The Shortt clock
maintains the relative *phase* of the two clocks by brief adjustments to
the frequency via a spring. This is controlled by measuring the relative
*phase* of the two clocks.


Wrong! It does NOT measure the relative phase, it makes NO measurement of
the phase difference. All it does is detect if there is a phase lag of any
degree. It could be a fraction of a degree or 180 degrees, the same
correction is then applied regardless.

....and that is a measurement. It determines if the relative phase is plus
or minus, a binary measurement. This is exactly the same as the measurement
taken by a 1 bit ADC. Even though it is one bit it is still a measurement.


It's that simple. You are just making things more complicated by talking
about the details of how the adjustment works and the time function of the
frequency. NO PLL can keep the two clocks perfectly in sync.

Calling it open loop is just absurd. The loop is closed because it
*measures* the phase of the clocks and adjusts the phase according to the
measurement. It may be binary, but the adjustment is controlled by the
measurement.

Wrong again it is open loop, there is no measurement, just the same
adjustment regardless of the phase difference.

Totally wrong. The phase adjustment varies from a constant about to ZERO!
Again it is a binary adjustment.

If there was a three level range of measurement and adjustment +, 0, -,
would that be enough to constitute a measurement and adjustment so it
becomes a PLL? If not, how many bits are required? If any number of bits
can't do it are digital PLLs not PLLs?

--

Rick C

A mechanical phase locked loop!
 

On 06/08/2017 15:27, Chris wrote:
On 08/06/17 12:52, Gareth's Downstairs Computer wrote:
On 06/08/2017 12:24, Chris wrote:
On 08/06/17 10:38, Jeff wrote:

You are making pointless distinctions. A phase locked loop is not
defined by its mechanics but by the nature of its control. The Shortt
clock maintains the relative *phase* of the two clocks by brief
adjustments to the frequency via a spring. This is controlled by
measuring the relative *phase* of the two clocks.


Wrong! It does NOT measure the relative phase, it makes NO measurement
of the phase difference. All it does is detect if there is a phase lag
of any degree. It could be a fraction of a degree or 180 degrees, the
same correction is then applied regardless.

It's that simple. You are just making things more complicated by
talking about the details of how the adjustment works and the time
function of the frequency. NO PLL can keep the two clocks perfectly in
sync.

Calling it open loop is just absurd. The loop is closed because it
*measures* the phase of the clocks and adjusts the phase according to
the measurement. It may be binary, but the adjustment is controlled by
the measurement.

Wrong again it is open loop, there is no measurement, just the same
adjustment regardless of the phase difference.

Jeff



Might be easier to define a set entitled "Locked Oscillators, of which
the phase locked loop, injection locked and hit and miss synchronised
are all members.

Are there other candidates ?...

From pre-war, the Goyder Lock?

Which raises an interesting point; before the 3-tier
coffer-filling fiasco was the spawn of the RSCB, the candidature
for the RAE tended to know all about the history of amateur radio
before getting their licence, but now they seem to know
sweet FA even after getting their licences, such as the
difference between sideband and sidetone.




Hadn't heard of that, so looked it up and found:

http://www.dxmaps.com/discuss/oven.html

Which was an interesting read, but not enlightening.

Some of the early scope timebases, puckle, for example sounded
interesting, but they were effectively injection lock, of course.
I guess a triggered timebase is a variation of the hit and miss model.

Couldn't grok the relevance of the following paragraph above :-)...


It relates to the abysmal lack of technical acumen amongst those
who are today's would-br radio amateurs, most of whom are
really CBers-masquerading-as-radio-hams, identifiable by their
M3 and M6 callsigns past and present.

A mechanical phase locked loop!
 

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.

A mechanical phase locked loop!
 

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?

--

Rick C

A mechanical phase locked loop!
 

On 06/08/2017 18:37, Gareth's Downstairs Computer wrote:
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.



Nothing in any of rick's posts he does understand the above, or anything
else. Plus, what you have posted is exactly what I explained to you
earlier.

It is clear you are on the edge of resorting to your normal abuse.

A mechanical phase locked loop!
 

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.

A mechanical phase locked loop!
 

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.

A mechanical phase locked loop!
 

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.

A mechanical phase locked loop!
 

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 /
http://twitter.com/ukradioamateur

A mechanical phase locked loop!
 

On 08/06/17 17:34, Gareth's Downstairs Computer wrote:


It relates to the abysmal lack of technical acumen amongst those
who are today's would-br radio amateurs, most of whom are
really CBers-masquerading-as-radio-hams, identifiable by their
M3 and M6 callsigns past and present.


Perhaps you are right, but does that matter ?. Might not all have
the tech ability of the past, but just as keen on operating and
the social aspects of the hobby. We can't all be tech experts, but
there are still plenty of deep tech areas for those interested.

Seems a bit of an elitist attitude really, speaking as one who
built his first one valve set at 11 and always more interested
in the tech side than operating...

Chris

A mechanical phase locked loop!
 

On 06/08/2017 19:58, Chris wrote:
On 08/06/17 17:34, Gareth's Downstairs Computer wrote:


It relates to the abysmal lack of technical acumen amongst those
who are today's would-br radio amateurs, most of whom are
really CBers-masquerading-as-radio-hams, identifiable by their
M3 and M6 callsigns past and present.


Perhaps you are right, but does that matter ?. Might not all have
the tech ability of the past, but just as keen on operating and
the social aspects of the hobby. We can't all be tech experts, but
there are still plenty of deep tech areas for those interested.

Seems a bit of an elitist attitude really, speaking as one who
built his first one valve set at 11 and always more interested
in the tech side than operating...

Elitism, yes, and something to be jealously guarded.

AIUI, there are already countries where only commercially
available rigs may be used, and by flooding this country
with technical numbskulls risks the powers-that-would-be
perceiving we all as operators only.

Amateur radio is primarily a technical pursuit with operation
being a trivially simple follow-on; so trivially simple, in fact,
that it is a nonsense to examine based upon operating. The 5-year-old
with her smartphone does not have to pass an exam on her operating
capability!

As to your last comment, Yes, more technician than operative,
I still maintain a logbook, with all test
and CQ calls logged, and yet after 47 years I'm only just half way
through my 2nd log book.

A mechanical phase locked loop!
 

On 06/08/2017 20:18, Gareth's Downstairs Computer wrote:
Amateur radio is primarily a technical pursuit with operation
being a trivially simple follow-on; so trivially simple, in fact,
that it is a nonsense to examine based upon operating.

If operating is so trivially simple why couldn't you tune the PA in the
radio you bought? Even CBers can do that.

A mechanical phase locked loop!
 

mm0fmf wrote:

On 06/08/2017 20:18, Gareth's Downstairs Computer wrote:
Amateur radio is primarily a technical pursuit with operation
being a trivially simple follow-on; so trivially simple, in fact,
that it is a nonsense to examine based upon operating.

If operating is so trivially simple why couldn't you tune the PA in the
radio you bought? Even CBers can do that.

Do you need to trade silly (and, yes, typically junior school stuff)
abuse rehearsed from interminable local arguments all over the Internet?
Why not keep this childish repetitive stuff for ukra where it "belongs"?
You *are* an adult, aren't you? Gareth's silly comments are quite
obviously silly comments without you clutttering the place up arguing
with him about it. If you think his comments about operating being too
easy and of no interest are inaccurate, why not say so, at least it will
soon be obvious he is in a minority of one? I for instance have very
little interest in operating but agree that it is an essential and
worthy part of the hobby (and not so easy as Gareth thinks) so why not
stick to the actual issue when discussing it internationally and outside
of the AR groups?



--

Roger Hayter

A mechanical phase locked loop!
 

Gareth's Downstairs Computer wrote on 8/6/2017 2:15 PM:
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.

Sorry, I was talking about how the Shortt clock adjusts the timing of the
slave pendulum. What are you talking about?

--

Rick C

A mechanical phase locked loop!
 

On 06/08/2017 22:15, rickman wrote:
Gareth's Downstairs Computer wrote on 8/6/2017 2:15 PM:
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.

Sorry, I was talking about how the Shortt clock adjusts the timing of
the slave pendulum. What are you talking about?


This is one of Evans' usual tactics Rick, he is out of his depth so he
is trying to muddy the water. Before long he will be hurling abuse in
earnest.

A mechanical phase locked loop!
 

On 06/08/2017 22:15, rickman wrote:
Gareth's Downstairs Computer wrote on 8/6/2017 2:15 PM:
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.

Sorry, I was talking about how the Shortt clock adjusts the timing of
the slave pendulum. What are you talking about?


I ... explained it for you in excruciating detail.

A mechanical phase locked loop!
 

Gareth's Downstairs Computer wrote on 8/6/2017 6:10 PM:
On 06/08/2017 22:15, rickman wrote:
Gareth's Downstairs Computer wrote on 8/6/2017 2:15 PM:
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.

Sorry, I was talking about how the Shortt clock adjusts the timing of the
slave pendulum. What are you talking about?


I ... explained it for you in excruciating detail.

No, you simply state that the circular error exists for pendulum clocks and
that the swing of the Shortt clock slave pendulum is shortened a small
amount. You imply the shorter swing of the pendulum invokes the circular
error factor to change the speed of the pendulum changing the phase.

None of that is wrong. But the circular arc error a very small effect. As
I have clearly explained to you the leaf spring also causes the first order
effect of changing the constant in the pendulum equation. This is a *much*
larger effect than the small circular error effect.

You say you understand what I am saying, but it directly shows what you are
describing is at best, a second order effect. If you don't disagree with
that how can it be tangential to what you are saying? Or is that a play on
words with the circular error???

--

Rick C