how to reduce speed/ amplitude of electronic pendulum??

[N_Cook]

To me the way that makes the most sense is to completely uncouple the
two functions. The accuracy of the cheapest quartz movement is far
better than you can get with the most precise pendulum. The most
efficient pendulum is one that oscillates at it's native frequency.
Googeling electronic pendulum drive circuit yields a great deal of
information, including some designs that simply provide a boost to a
pendulum at it's native frequency. Most of the designs did nothing to
optimize drive current.

PlainBill

Perhaps you could gate the output drive by a divide by 10 counter on the
clock ouput and only power kick every tenth swing of the pendulum. Would
conserve battery and perhaps less amplitude of swing

 

[William Sommerwerck]

What you say makes sense -- but the drive circuit will always compensate

To me the way that makes the most sense is to completely uncouple the
two functions. The accuracy of the cheapest quartz movement is far
better than you can get with the most precise pendulum. The most
efficient pendulum is one that oscillates at it's native frequency.

ALL pendulums oscillate at their native frequency. They can't help but.

Googeling electronic pendulum drive circuit yields a great deal of
information, including some designs that simply provide a boost to a
pendulum at its native frequency.

You're missing the point. The pendulum presumably drives the clock gears. If
all you care about is "efficiency", switch to an all-electronic clock with
an LCD.

If you're going to power the pendulum electronically, it makes sense to have
a system that keeps the pendulum running at the "right" frequency. The
system I described allows the pendulum frequency to be tweaked without
mechanical adjustments.

 

[[email protected]]

ALL pendulums oscillate at their native frequency. They can't help but.

Only true if you add the qualifier 'if there are no additional
forces'. A great deal of effort is required to ensure this is true.
Did you ever wonder why the best Grandfather clocks use weights to
provide power?

In a happier time my wife decided we needed a real pendulum clock on
the mantle of our new (to us) home. She picked up one (made in Korea)
that required monthly winding. With a little care I could adjust it
so it was correct at the begining of the month and again at the end of
the month. The force provided by the spring changed depending on how
tight it was, this changed the force on the escapement, which changed
to force applied to the pendulum. The clock would gain time at the
beginning of the month and lose it toward the end of the month.

Look attractive? Yes. Sound good? Definitely. Keep good time - no
way.

PlainBill

 

[William Sommerwerck]

What you say makes sense -- but the drive circuit will always
compensate

Only true if you add the qualifier 'if there are no additional
forces'. A great deal of effort is required to ensure this is true.
Did you ever wonder why the best Grandfather clocks use
weights to provide power?

No, I never wondered, because I knew why. And it's energy, not power, by the
way.

 

[N_Cook]

Only true if you add the qualifier 'if there are no additional
forces'. A great deal of effort is required to ensure this is true.
Did you ever wonder why the best Grandfather clocks use weights to
provide power?

In a happier time my wife decided we needed a real pendulum clock on
the mantle of our new (to us) home. She picked up one (made in Korea)
that required monthly winding. With a little care I could adjust it
so it was correct at the begining of the month and again at the end of
the month. The force provided by the spring changed depending on how
tight it was, this changed the force on the escapement, which changed
to force applied to the pendulum. The clock would gain time at the
beginning of the month and lose it toward the end of the month.

Look attractive? Yes. Sound good? Definitely. Keep good time - no
way.

PlainBill

Thats why fusees were invented, but could only compensate to a certain
extent

 

[William Sommerwerck]

units analysis ... probably isn't the right term, but I can't think of
what it is.

Dimensional analysis?

That's it! Thank you.

 

[Leif Neland]

Efter mange tanker skrev N_Cook:

Human clocks are the same. Put a human in a cave, out of touch with the
outside world, and his natural day-length reverts to about 24.5 to 25 hour
days, requires the sun etc to sync him to 24 hour days

Not all people "run slow". Some "run fast". These are the people with
the nasty habit of waking up at 5AM pestering the other half until the
early birds go to sleep when the late risers want to have fun.

If you are locked in the office/shop/factory all the hours with
daylight, and never seeing the light of day during the winter, you can
get depressed; this can be reduced by, in the morning, looking into a
strong "wake-up-lamp" designed to have the spectrum of sunlight.