simple frequecny multiplier

measurment?

oscilator?

comparing two

stability.

compromise

Farnell. I

do some

stabilty

devices

ok look up SAW (Surface Acoustic Wave) Oscialltors

but are you saying that you are going to use two seperate oscillators and measure the change in the their frequency and or phase comparing one to the other to do some speed of light measurements. I don't think it will work. The accuracy of any two oscillators that you can buy will not be good enough for this (unless one is going to go REALLY REALLY fast).

I suggest you design the experiment so that you use only ONE oscillator and split it's signal send them through two paths and compare the two signals that come out of the same oscillator. Then the stability of the oscillator is not as important.

Also look up interferometer (I may have spelled that worng)

have fun

Mark

Are you trying to measure the speed of the earth through the aether?

John

wel yes its pretty much like a ring gyro, exept its for detecting linear motion rather than rotational motion. this has been more dificult becuse a rotational gyro can use the same laser to transmit the signal and compare it with the received signal, but you cant do this with a linear device becuase the comparison signal would have to travel the same path as the transmited signal to arive at the detector and so would undergo the same propagation delay change. however the Silvertooth experiment did it with a single light source but i dont realy understand the explanation as to how it avoided this problem, also it required a highly specialised detector and elaberate optical setup and was i beleive rather tempermental, and i have not heard of it being repeated so i am interested in doing this.

im therfore using two clocks 1 meter apart that are synchronised to be precisly in phase over a long average time then rotating them say about

Colin =^.^=

haha very funny (not), wel somthing already configured and tested would be fine and cheaper than the test equipment to check it, but theres only a few components in a x5 multiplier and if you carefully folow an exising design its not too far fetched to expect it to pick out the right frequency. you can easily fine tune it to maximum output with a snifer probe asuming there isnt more than one frequency selectable within the tuning range.

Colin =^.^=

Forget an interferometer. The mechanical noise in an optical system is tremendous. It picks up whatever accoustical vibration that couples into the case. A sort of expensive microphone. There you achieve a

Rene

I read in sci.electronics.design that John Larkin wrote (in ) about 'simple frequecny multiplier', on Thu, 7 Apr 2005:

It is suspected of exceeding the speed limit, and we will all be fined $10 each.

There should be a required PSEUDOSCIENCE AMATEUR heading for threads like this. That would save us a lot of time.

John

Same thing.

Nothing wrong with that.

I believe the M&M experiment has been repeated with lasers at something like 1000x the original sensitivity, with the same null result.. I believe also that Sivertooth is a whacko.

LIGO is interesting in this respect.

John

Shortly after HP introduced their cesium clock (it's a huge, heavy rackmount thing... we have one) they bought two round-the-world airline seats, one for an engineer and one for the clock with battery backup. They synched two clocks then flew one around the world. The flying clock was slower by a few ns, just what relativity predicted. It was written up in the HP Journal.

John

Well im sorry if you feel youve wasted your time, but i do apreciate your other comments.

I got the multiplier working quite easily in the end, and over a long time the control voltage from the PLL doesnt seem to change that I can detect on a 4 digit meter, however the short term phase movement was rather disapointing, I tried your idea of using a heavy aluminium can on the XO but this made little diference. one oscilator definatly seemed to be far more sensitive to anything going near it over the short term than the other but the control voltage always quickly returned to the same value and never moved more than a few milivolts even when touching it with a finger.

These fairly new TC devices from CMAC looked quite good on the product description and seem to perform as brilaintly as they claim over longer time intervals, but like you sugested isnt realy a match for the themral time response and beter operating point of the oven types, wich is a shame.

So I have some cheap OCXO coming soon i hope.

The best OCXO i could find were again from CMAC and they quoute the 1hz phase noise as low as -120db and short term stability over 1S as 2x10-13 wich is obviously ideal, but probably prohibitvly expensive, or hard to obtain.

Im not building a dvice to measure the speed of the earth through the aether as you put it (thats suposed to have been proven not to exist) but something simple and reproducabble that can actualy demonstrate that the speed of light in one direction only isnt (or maybe is) afected by it. Most such experimants have only one source and so inevitably take the speed of light averaged over a return path in order to compare it with the originating source.

I would feel sorry for Michelson, Morley and Sivertooth who have investigated this too, if they are to be condsidered as pseudoscience amatteurs. I dont see whats wrong with building something to measure such fundemental scientific principles, using technlogy thats improved since it was first performed over a century ago. (principles that some say are defied by the ring gyros you mentioned.)

Il keep quiet if i detect its moving over 100mph as its an automatic ban here, however i hear the Vogons are going to build an intergalactic highway through this way soon so maybe the speed restriction wil be lifted.

Colin =^.^=

light

The Laser Gyro would obviously not work if it had to reflect the light path back along the circular fibre, wich is my point for avoiding this in this experiment too. fortunatly for a circular path there is no need to do this as it conveniently comes back to the original source. The return path tends to virtualy cancel out any change in delay exept for very high velocities.

Although the sensitivity of Laser interfermotery can be execeptionaly high, you are suming a very small delay with a very smal and almost identical negative delay. This result is exceptionaly small, and some claim certain mathmatical aproaches (wich might seem dubious) prove this is always a null result, I realy dont wish to debate this last point however as its extremly tiresome and i dont understand some of the maths used well enough to point out or understand any errors in it, there seems to be so much hot air about this issue.

However for measuring the speed of light in a single direction with no such return path there can be no such mathmatical issues, especialy by comparing it with the speed in the oposite direction.

The problem with the silvertooth experiment is that it wasnt exactly repeatable and as it contradicted such strongly held ideas it was inevitable people viewed him that way, personaly i do not believe his explanation of how it gave a result diferent to the M&M experiment. However it did apear in wireless world in 1996 wich i thought of as a well regarded journal at the time, and made me think about it.

It is interesting, and i thought if there was a simple way of proving it one way or the other I would give it a go, the electronics and mechanics of this aproach realy is very simple indeed, although it does rely heavily on incredible accuracy from the clocks, i had envisaged using 2 atomic clocks many years ago wich was obviously impractical as they wernt exactly very movable, however modern XO etc have come a long way and many are claimed to be more acurate than atomic clocks now and only revently did i think it was feasable. The other way i envisaged was to use a freely rotating shaft the ends of wich would always be in perfect angular synch and provide the clock source at each end but might be hard to meet mechanical constraints.

If the device can be built with reasonably obtainable parts without the need for exeptionaly high precision and so would be easily repeatable there would be little need for any further confusion, and may even be demonstrated in the classroom, however i realy must confess i am not totaly convinced about the result, there does seem to be some genuine conflict for either retult, however I would be rather woried if it contradicted the mainstream thinking. there seems to be little comercial aplication for such an effect if it was detectable though, unlike the laser gyros wich are cool.

Yes it seem interesting im going to look at that just now.

Colin =^.^=

ok, here is what I suggest you do....

the carrier frequency of WWV is exactly 10MHz. It is more accurate then any oscillator you can get your hands on.

You can receive that and measure the frequency at your home. (You will need one very accurate oscillator to make that measurment but thats another detail.)

Continue to monitor the frequency of WWV for 1 year during which time the Earth will go around full circle. If you detect any change in the measured frequency of WWV, let us know.

Mark

I read in sci.electronics.design that Mark wrote (in ) about 'simple frequecny multiplier', on Tue, 12 Apr 2005:

You didn't happen to mention that the other accurate oscillator must stay suspended in space while the Earth orbits, or, better still, make it orbit the Sun in the opposite direction to the Earth. Just remember to dodge after six months.

Although sounds like a very interesting experiment, I unclear as to what you think this will measure apart from the acuracy of my local clock. Unless you mean i could extrapolate the varying phase change from the change in frequency this would be more dificult than what i am trying to do i think. phase errors in the signal pasing through the atmosphere would be to great.

If there was a fiber optic cable between two places that both had reference clocks you could do this. although the acuracy needed over 24 hours is a lot more demanding than over 1 second the a distance of several 100km wil comepnsate.

All i need to do this acruratly is to have two clocks wich can free run and stay precisly matched to eachother over a 1 second period, or maybe a lot less if i spin it realy fast. absolute oscilation freq is far less important. of course dont forget i can also integrate the signal over as long as necessary.

As i mentioned before another alternative is to have 2 lasers wich can be tuned to match eachother, I havnt looked into what sort of performance i could expect from this.

Colin =^.^=

If you had a reference clock on mars as well as earth the relative velocity between the two planets various enoumously over 2 years or so, and so the speed of the clocks should also vary significantly or wobble, however if you were an observer on the sun you presunably would not see any such wobble from either clock.

Colin =^.^=

well if you believe the earth is travel though an aether of some sort (which I don't) then you will detect a change in the received frequency of WWV as the earth rotates and travels around the sun because sometimes the signal from WWV will be traveling parallel to the aether wind and sometimes it will be traveling perpendicular to the wind. And unlike the MM experiment, which you apparently don't believe in because it is a two way round trip path, the path from WWV to your house is a one way path.

Mark

"colin" a écrit dans le message de news:tZW6e.20610$ snipped-for-privacy@newsfe5-win.ntli.net...

velocity

you

And you said that you were short on your budget?

Wow :-)

the

Any contributions gladly accepted :D (i just won some cheap ocxos on ebay so thats a good start)

Colin =^.^=

Well, the one ring gyro that I did have an opportunity to manhandle did, in fact, verify that the ether wind does NOT cause doppler shift between the incident beam and the reflected one.

I could tell it was working, because they had their interferometer coupled to an audio amp. You could hear it move when you touched it.

Cheers! Rich