Novel Zeitgeber devive for antique clock

You mechanically injection-locked it, perhaps? Pendulum clocks will lock to each other if you put them close together on a wooden floor.

Cheers

Phil Hobbs

cuit to make it very accurate. I did not use a sensor, nor did I modify the clock's mechanism or its iron pendulum bob in any way. There is absolutely no circuit or sensor which measures the clock.

ntly..)

That's close...

A coil below the pendulum, pulsed properly, would work.

It should lock to a coil driven from 60 Hz (resistor+diode from AC line) and it might not even need the diode.

Injection locking is fun. I think James has a patent or two.

Parametric entrainment with a magnetic coil at the bottom of the swing driven from a crystal at twice the natural swing of the pendulum but crystal controlled. The pendulum will phase lock to the energy source and only a modest drive needed.

There is a variant of this that can be used to do the Indian rope trick with a broomhandle.

You are being a PITA. You're probably a nym of Jim Thompson.

It's been done for decades. googling this will produce thousands of hits.

rcuit to make it very accurate. I did not use a sensor, nor did I modify th e clock's mechanism or its iron pendulum bob in any way. There is absolutel y no circuit or sensor which measures the clock.

ently..)

and it

yes, that's it. The hint about the iron bob was that the electromagnet was involved. jb

circuit to make it very accurate. I did not use a sensor, nor did I modify the clock's mechanism or its iron pendulum bob in any way. There is absolut ely no circuit or sensor which measures the clock.

erently..)

OK my apologies. I have seen various sensor systems, but not this. Ever seen those wind mill s on towers turning in synchrony? Wonder how that happens?

That's been done a lot, as you say. Of course it has a dead zone right around lock, so the phase noise would be horrible. ;) (You just have to put it slightly off center.)

That's a fun possibility. I wonder how close to 1 Hz it would have to be in order to lock. The locking time would be pretty long, I expect.

Using a vibrator motor or something like that, you could probably make an aftermarket injection locker for pendulum clocks that would require zero mods to the clock. (I can just see an Android app for that. Probably possible in some instances.) ;)

Cheers

Phil Hobbs

On Friday, January 31, 2014 7:24:33 AM UTC-8, snipped-for-privacy@gmail.com wrote: [about locking a pendulum to an electronic source]

There's a nice (expired) patent on this (US patent 3783550), and a cute little toy called "Top Secret" based on the same principle, but with added obfuscation...

You mechanically injection-locked it, perhaps? Pendulum clocks will lock to each other if you put them close together on a wooden floor. Cheers

Phil Hobbs

Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics

hobbs at electrooptical dot net

Why are you always trying to pick a fight? What a waste of (supposed) talent. ...Jim Thompson

And yet they still tune the Big Ben in Londen by adding or removing coins. I'll give them a ring on monday...

You probably could acoustically injection lock it with a speaker thumping rhythmically >:-} ...Jim Thompson

Got to fill up the post with something... Larkin is like a lot of spam E-mail I get that uses random filler words to get past the filters. ...Jim Thompson

Fight? With you? More like clubbing baby seals.

How about a box that you stick to the back of the clock with velcro or something. Inside is a 1 RPS (or is that 0.5 RPS?) synchronous motor driving an eccentric weight on its shaft. It would slightly rock the clock case, probably not noticable.

Yep. That's certainly the kind of "person" you are. ...Jim Thompson

Pendulum driven by a solenoid? I think we are talking about adding a synchronizer to a mechanical clock without altering the original clock mechanism.

I was thinking that a coil pulsed at 60 Hz could be put just below the arc of the pendulum. If the interaction distance/time were small, there would be a decent synchronizing force.

Because we're talking about injection locking here, and it's an electronics discussion group.

Injection locking usually involves a high frequency oscillator and a lower frequency pump. But there's no reason the other direction wouldn't work, like a 1 Hz pendulum pumped by a 60 Hz coil. A coil and a diode, and maybe a resistor, is a lot easier to make than some electronics, and the 60 Hz line is practically the definition of time.

Come on, generate some ideas, instead of whining all the time.