Re: [time-nuts] Vibration isolation of quartz oscillators

[Bob kb8tq]

Hi

There are tables made for low vibration test setups. They are (essentially) a 
big heavy cast 
iron table sitting on air cushions under each of the legs. Not a great approach 
for a low G 
OCXO ….

Bob

> On Jun 27, 2020, at 8:09 PM, Neville Michie  wrote:
> 
> An old trick I learned from an Australian standards lab was to make a 
> vibration free
> table with a 2 foot by 2 foot by 2 inch paving slab supported by a partly 
> inflated 
> wheel barrow inner tube.
> I tried it recently for measurements of force in an electric clock movement 
> and it cut out the background vibration in a spectacular way.
> cheers, Neville Michie
> 
>> On 27 Jun 2020, at 22:02, Michael Wouters  wrote:
>> 
>> I have three Oscilloquartz 8607-Bs that I'm rehousing.
>> 
>> In their former life they were part of the frequency synthesis chains
>> for H-masers and they hung vertically from a rubber suspension that was
>> presumably intended to provide vibration isolation. Unfortunately, the
>> person responsible for this has long since retired so is no longer
>> around to ask questions of.
>> 
>> In the experiment I will be averaging over  100 s, which suggests to
>> me that very low frequencies are what I need to filter out (if at
>> all), and I am skeptical that the rubber will do this. Space is tight
>> so I am wondering
>> whether I should simply ditch the isolation.
>> 
>> What do other people do with their quartzes ? I thought I should ask
>> for some advice before attempting measurements.
>> 
>> Cheers
>> Michael
>> 
>> ___
>> time-nuts mailing list -- time-nuts@lists.febo.com
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>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
>> and follow the instructions there.
> 
> 
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Re: [time-nuts] Vibration isolation of quartz oscillators

[Neville Michie]

An old trick I learned from an Australian standards lab was to make a vibration 
free
table with a 2 foot by 2 foot by 2 inch paving slab supported by a partly 
inflated 
wheel barrow inner tube.
I tried it recently for measurements of force in an electric clock movement 
and it cut out the background vibration in a spectacular way.
cheers, Neville Michie

> On 27 Jun 2020, at 22:02, Michael Wouters  wrote:
> 
> I have three Oscilloquartz 8607-Bs that I'm rehousing.
> 
> In their former life they were part of the frequency synthesis chains
> for H-masers and they hung vertically from a rubber suspension that was
> presumably intended to provide vibration isolation. Unfortunately, the
> person responsible for this has long since retired so is no longer
> around to ask questions of.
> 
> In the experiment I will be averaging over  100 s, which suggests to
> me that very low frequencies are what I need to filter out (if at
> all), and I am skeptical that the rubber will do this. Space is tight
> so I am wondering
> whether I should simply ditch the isolation.
> 
> What do other people do with their quartzes ? I thought I should ask
> for some advice before attempting measurements.
> 
> Cheers
> Michael
> 
> ___
> time-nuts mailing list -- time-nuts@lists.febo.com
> To unsubscribe, go to 
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
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Re: [time-nuts] Vibration isolation of quartz oscillators

[Tom Knox]

Hi Michael;
I know Craig Nelson, Archita Hati, and Dave Howe were doing some related 
research at NIST. I did a quick search and think this may be the paper, but 
there may be others.
As I remember cable vibration can be a greater uncertainty then the oscillator.
https://www.intechopen.com/books/aerial_vehicles/vibration-induced_pm_noise_in_oscillators_and_its_suppression
[https://cdn.intechopen.com/books/images_new/3696.jpg]
Vibration-Induced PM Noise in Oscillators and Its Suppression | 
IntechOpen
Archita Hati, Craig Nelson and David Howe (January 1st 2009). Vibration-Induced 
PM Noise in Oscillators and Its Suppression, Aerial Vehicles, Thanh Mung Lam, 
IntechOpen, DOI: 10.5772/6476. Available from:
www.intechopen.com
Cheers;

Tom Knox

SR Test and Measurement Engineer

Ascent Concepts and Technology

4475 Whitney Place

Boulder Colorado 80305

303-554-0307

act...@hotmail.com

"Peace is not the absence of violence, but the presence of Justice" Both MLK 
and Albert Einstein


From: time-nuts  on behalf of Tom Van Baak 

Sent: Saturday, June 27, 2020 12:56 PM
To: time-nuts@lists.febo.com 
Subject: Re: [time-nuts] Vibration isolation of quartz oscillators

Michael,

These are really good oscillators so in addition to guessing what sounds
like a good solution verify with actual vibration / acceleration
experiments.

Last year I tested some Oscilloquartz BVA's for axis sensitivity to
acceleration. It's quite easy. Some plots here:

http://leapsecond.com/pages/bva-rotate/

At the end of that page are two videos showing the Arduino-driven
stepper motor rotating platform that I used. If anyone can't view the
videos let me know off-list (my email is t...@leapsecond.com).

If you end up doing something similar I would very much like to see how
your results compare.

Thanks,
/tvb


On 6/27/2020 5:02 AM, Michael Wouters wrote:
> I have three Oscilloquartz 8607-Bs that I'm rehousing.
>
> In their former life they were part of the frequency synthesis chains
> for H-masers and they hung vertically from a rubber suspension that was
> presumably intended to provide vibration isolation. Unfortunately, the
> person responsible for this has long since retired so is no longer
> around to ask questions of.
>
> In the experiment I will be averaging over  100 s, which suggests to
> me that very low frequencies are what I need to filter out (if at
> all), and I am skeptical that the rubber will do this. Space is tight
> so I am wondering
> whether I should simply ditch the isolation.
>
> What do other people do with their quartzes ? I thought I should ask
> for some advice before attempting measurements.
>
> Cheers
> Michael
>
> ___
> time-nuts mailing list -- time-nuts@lists.febo.com
> To unsubscribe, go to 
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>

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Re: [time-nuts] Vibration isolation of quartz oscillators

[Adrian Godwin]

Would a mechanical image-stabilisation system work ?

https://en.wikipedia.org/wiki/Image_stabilization#Stabilizing_the_camera_body


On Sat, Jun 27, 2020 at 7:58 PM Tom Van Baak  wrote:

> Michael,
>
> These are really good oscillators so in addition to guessing what sounds
> like a good solution verify with actual vibration / acceleration
> experiments.
>
> Last year I tested some Oscilloquartz BVA's for axis sensitivity to
> acceleration. It's quite easy. Some plots here:
>
> http://leapsecond.com/pages/bva-rotate/
>
> At the end of that page are two videos showing the Arduino-driven
> stepper motor rotating platform that I used. If anyone can't view the
> videos let me know off-list (my email is t...@leapsecond.com).
>
> If you end up doing something similar I would very much like to see how
> your results compare.
>
> Thanks,
> /tvb
>
>
> On 6/27/2020 5:02 AM, Michael Wouters wrote:
> > I have three Oscilloquartz 8607-Bs that I'm rehousing.
> >
> > In their former life they were part of the frequency synthesis chains
> > for H-masers and they hung vertically from a rubber suspension that was
> > presumably intended to provide vibration isolation. Unfortunately, the
> > person responsible for this has long since retired so is no longer
> > around to ask questions of.
> >
> > In the experiment I will be averaging over  100 s, which suggests to
> > me that very low frequencies are what I need to filter out (if at
> > all), and I am skeptical that the rubber will do this. Space is tight
> > so I am wondering
> > whether I should simply ditch the isolation.
> >
> > What do other people do with their quartzes ? I thought I should ask
> > for some advice before attempting measurements.
> >
> > Cheers
> > Michael
> >
> > ___
> > time-nuts mailing list -- time-nuts@lists.febo.com
> > To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> > and follow the instructions there.
> >
>
> ___
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Re: [time-nuts] Vibration isolation of quartz oscillators

[Hendrik]

You might try a sandwich of rubbery or foamy stuff alternating with
heavy, stiff stuff, like silicon pads/steel plate. And keep air drafts away.

At least that method I am about to try to decouple my geophones during
experiments.

BR

Hendrik



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Re: [time-nuts] Vibration isolation of quartz oscillators

[Tom Van Baak]

Michael,

These are really good oscillators so in addition to guessing what sounds 
like a good solution verify with actual vibration / acceleration 
experiments.


Last year I tested some Oscilloquartz BVA's for axis sensitivity to 
acceleration. It's quite easy. Some plots here:


http://leapsecond.com/pages/bva-rotate/

At the end of that page are two videos showing the Arduino-driven 
stepper motor rotating platform that I used. If anyone can't view the 
videos let me know off-list (my email is t...@leapsecond.com).


If you end up doing something similar I would very much like to see how 
your results compare.


Thanks,
/tvb


On 6/27/2020 5:02 AM, Michael Wouters wrote:

I have three Oscilloquartz 8607-Bs that I'm rehousing.

In their former life they were part of the frequency synthesis chains
for H-masers and they hung vertically from a rubber suspension that was
presumably intended to provide vibration isolation. Unfortunately, the
person responsible for this has long since retired so is no longer
around to ask questions of.

In the experiment I will be averaging over  100 s, which suggests to
me that very low frequencies are what I need to filter out (if at
all), and I am skeptical that the rubber will do this. Space is tight
so I am wondering
whether I should simply ditch the isolation.

What do other people do with their quartzes ? I thought I should ask
for some advice before attempting measurements.

Cheers
Michael

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Re: [time-nuts] Vibration isolation of quartz oscillators

[Bob kb8tq]

Hi

Accelerometer compensation of OCXO’s is indeed possible. There are parts out 
there
that will do the job. Phase shift is your enemy in this case. You are trying to 
get two AC
signals to sum to zero. Fairly small phase shifts will limit the “floor” of a 
process like this. 
Mounting the accelerometer *very* close to the blank is the key. In a large 
package part
like the 8700 series / working from the outside …. yikes ….. Your “max 
frequency” is going
to be mighty low. Forget about taking care of fan blade noise ….

Bob

> On Jun 27, 2020, at 10:29 AM, Dana Whitlow  wrote:
> 
> If compactness is needed and you're operating in anything like a 1 g field,
> I think that
> it will be impossible to do a spring suspension that is both compact and
> effective
> down to the milli-Hz level (or less).
> 
> It might be worthwhile doing a compensation scheme based on a 3-axis
> accelerometer
> (one should suffice for multiple oscillators) whose outputs are scaled and
> combined
> to form a single signal (per oscillator) to be summed into the EFC input.
> 
> But some strong caveats immediately come to mind:
> 1. Noise in the accelerometers' outputs.
> 2. Dealing with the inevitable tuning nonlinearity of the oscillators.
> 3. Calibrating the compensation system well enough to satisfy.
> 
> Good luck.
> 
> Dana
> 
> 
> On Sat, Jun 27, 2020 at 7:38 AM Michael Wouters 
> wrote:
> 
>> I have three Oscilloquartz 8607-Bs that I'm rehousing.
>> 
>> In their former life they were part of the frequency synthesis chains
>> for H-masers and they hung vertically from a rubber suspension that was
>> presumably intended to provide vibration isolation. Unfortunately, the
>> person responsible for this has long since retired so is no longer
>> around to ask questions of.
>> 
>> In the experiment I will be averaging over  100 s, which suggests to
>> me that very low frequencies are what I need to filter out (if at
>> all), and I am skeptical that the rubber will do this. Space is tight
>> so I am wondering
>> whether I should simply ditch the isolation.
>> 
>> What do other people do with their quartzes ? I thought I should ask
>> for some advice before attempting measurements.
>> 
>> Cheers
>> Michael
>> 
>> ___
>> time-nuts mailing list -- time-nuts@lists.febo.com
>> To unsubscribe, go to
>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
>> and follow the instructions there.
>> 
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Re: [time-nuts] Vibration isolation of quartz oscillators

[Richard (Rick) Karlquist]

On 6/27/2020 5:48 AM, Gerhard Hoffmann wrote:


Am 27.06.20 um 14:02 schrieb Michael Wouters:


What do other people do with their quartzes ? I thought I should ask
for some advice before attempting measurements.


A sand box? Literally? Some bags filled with sand really helped

with my turntable. Make sure that it stays in the bags.


Gerhard




There was a turntable stand with the creative
name "lead balloon" that worked like your sand
box (I actually don't know what substance the
"lead" balloon used for ballast).

You might also consider locating the oscillator
in your garage/basement on the concrete.  The
ideal setup is to pour concrete for a "floor
safe" sort of container and then mount the
oscillator inside the container below ground
level.  For the advanced user, dig a 5 foot
deep hole with a post hole digger than put
in a pipe with the oscillator at the bottom.
As a free bonus, you will get temperature
stabilization.

Rick N6RK

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Re: [time-nuts] Vibration isolation of quartz oscillators

[Tom Knox]

Hi Michael;
So what I did with one of my 8607's was placed it in a cast aluminum box with 
1/2 of soft silicon foam (it will never break down over time and heat) on all 
sides to provide not only mechanical isolation but thermal isolation as well. I 
actually did a bit more then that and would be glad to send you photos directly 
if interested. With an oscillator like the 8607 I think it is worth the effort.
Stay Safe;

Tom Knox

SR Test and Measurement Engineer

Ascent Concepts and Technology

4475 Whitney Place

Boulder Colorado 80305

303-554-0307

act...@hotmail.com

"Peace is not the absence of violence, but the presence of Justice" Both MLK 
and Albert Einstein


From: time-nuts  on behalf of Michael Wouters 

Sent: Saturday, June 27, 2020 6:02 AM
To: Discussion of precise time and frequency measurement 

Subject: [time-nuts] Vibration isolation of quartz oscillators

I have three Oscilloquartz 8607-Bs that I'm rehousing.

In their former life they were part of the frequency synthesis chains
for H-masers and they hung vertically from a rubber suspension that was
presumably intended to provide vibration isolation. Unfortunately, the
person responsible for this has long since retired so is no longer
around to ask questions of.

In the experiment I will be averaging over  100 s, which suggests to
me that very low frequencies are what I need to filter out (if at
all), and I am skeptical that the rubber will do this. Space is tight
so I am wondering
whether I should simply ditch the isolation.

What do other people do with their quartzes ? I thought I should ask
for some advice before attempting measurements.

Cheers
Michael

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Re: [time-nuts] Vibration isolation of quartz oscillators

[Chris Caudle]

On Sat, June 27, 2020 7:02 am, Michael Wouters wrote:
> I have three Oscilloquartz 8607-Bs that I'm rehousing.
>
> In their former life they were part of the frequency synthesis chains
> for H-masers and they hung vertically from a rubber suspension that was
> presumably intended to provide vibration isolation.

That sounds to me like isolation from local equipment vibrations, such as
fans in the same rack, or an air conditioning air handler that was bolted
to the same room structure.  Your assessment should be correct that that
type of suspension could not provide isolation in the deep sub-Hz region
that you say you are interested in.

-- 
Chris Caudle



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Re: [time-nuts] Vibration isolation of quartz oscillators

[ed breya]

I have mounted OCXOs, Rbs, and PLOs on small rubber motor mounts - the 
kind like for fan vibration reduction and such. The problem is that it's 
more of a guessing/empirical task, with no idea of the actual 
susceptibility of the device, or the mounting attenuation specs or 
degree of improvement, without doing actual mechanical vibration tests.


If you have access to a commercial shake table or driver, you can 
readily make such tests. You can make crude DIY shaker setups with 
motors or big loudspeakers to rattle things around, and with proper 
instrumentation, measure the acceleration, displacement, frequency, etc. 
It can get quite complicated though. In any case, with DUTs like these, 
you also have to isolate the effects of magnetic emissions from the 
mover, from the true mechanical displacement effects, by adequate 
shielding and distance, and making comparative measurements. It's a lot 
of stuff to go through.


I think the simplest approach, and most effective in all axes, would be 
to mount the unit in a box of rubbery foam padding material. Of course, 
with an OCXO, you don't want it to insulate too well - the power has to 
be dissipated, and the foam has to handle the operating case 
temperature, so the thermal and material issues would need to be worked out.


If the available space is too small for at least a cm or so foam all 
around, you can look for small vibration isolation mounts, which should 
be available in all sorts of characteristics. Another possibility is to 
suspend the unit assembly on a thin rubber sheet, or from metal 
expansion springs or rubber o-rings tensioned in opposing directions as 
needed. For metal springs, you'd want to use lightest "k" ones as 
possible, that will adequately support the mass, with bits of foam 
shoved inside them to dampen self-resonances. Anyway, there are a lot of 
of options, but you still won't know how well they work without actual 
testing.


Ed



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Re: [time-nuts] Vibration isolation of quartz oscillators

[Dana Whitlow]

If compactness is needed and you're operating in anything like a 1 g field,
I think that
it will be impossible to do a spring suspension that is both compact and
effective
down to the milli-Hz level (or less).

It might be worthwhile doing a compensation scheme based on a 3-axis
accelerometer
(one should suffice for multiple oscillators) whose outputs are scaled and
combined
to form a single signal (per oscillator) to be summed into the EFC input.

But some strong caveats immediately come to mind:
1. Noise in the accelerometers' outputs.
2. Dealing with the inevitable tuning nonlinearity of the oscillators.
3. Calibrating the compensation system well enough to satisfy.

Good luck.

Dana


On Sat, Jun 27, 2020 at 7:38 AM Michael Wouters 
wrote:

> I have three Oscilloquartz 8607-Bs that I'm rehousing.
>
> In their former life they were part of the frequency synthesis chains
> for H-masers and they hung vertically from a rubber suspension that was
> presumably intended to provide vibration isolation. Unfortunately, the
> person responsible for this has long since retired so is no longer
> around to ask questions of.
>
> In the experiment I will be averaging over  100 s, which suggests to
> me that very low frequencies are what I need to filter out (if at
> all), and I am skeptical that the rubber will do this. Space is tight
> so I am wondering
> whether I should simply ditch the isolation.
>
> What do other people do with their quartzes ? I thought I should ask
> for some advice before attempting measurements.
>
> Cheers
> Michael
>
> ___
> time-nuts mailing list -- time-nuts@lists.febo.com
> To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>
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Re: [time-nuts] Vibration isolation of quartz oscillators

[Bob kb8tq]

Hi

First thing to find out is what the per axis sensitivities of your oscillators
are. There should be significant variation between the three directions. 
What you find on one may or may not be what you find on the rest. 
Just about any source of (single directional) vibration will work for this test.
Measure the phase noise sidebands at the vibe frequency and go from
there. As long as the input is < 100 Hz you should be away. from any
internal resonances. 

Next step is to measure the vibe levels in your masers on an axis by axis
basis. This may take a while to do. You want to see what all the bumps and
thumps from operating this or that ( pump …) contribute. 

Conventional vibe isolators will help you above 100 Hz. If you have significant
energy up there, you may want to do a proper sweep of your OCXO’s on
a vibe table. There *will* be resonances ….

The rubber tubing (and other similar approaches) damping is aimed at getting
down into the 10’s or even single Hz range for significant attenuation. The 
trick is that you don’t want things very tight. Tight gets you more of a 
resonance.
You want damping. Hanging on a loose tube is better (attenuation wise) than
suspended between a set of tight tubes. 

Indeed having things hang loose inside the Maser is less than ideal if you ever
need to *move* the beast … there is a bit of a tradeoff. 

Wires and cables get into the act. Flexing a piece of coax can impart phase 
modulation. This is also worth watching out for when you test your OCXO’s. 
Taping the coax down is normally adequate when testing. 

Pretty much any good OCXO should have a worst case vector sensitivity
< 2 ppb / g. I would expect a good SC to be below 5x10^-10 / g. A good BVA
should be even better. 

What tubing works best? What lasts the longest? What do you have in stock?
I’d start with silicone based rubber tubing. It should last the longest. It’s 
also
fairly easy to get. 

Lots of fun !!

Bob

> On Jun 27, 2020, at 8:02 AM, Michael Wouters  
> wrote:
> 
> I have three Oscilloquartz 8607-Bs that I'm rehousing.
> 
> In their former life they were part of the frequency synthesis chains
> for H-masers and they hung vertically from a rubber suspension that was
> presumably intended to provide vibration isolation. Unfortunately, the
> person responsible for this has long since retired so is no longer
> around to ask questions of.
> 
> In the experiment I will be averaging over  100 s, which suggests to
> me that very low frequencies are what I need to filter out (if at
> all), and I am skeptical that the rubber will do this. Space is tight
> so I am wondering
> whether I should simply ditch the isolation.
> 
> What do other people do with their quartzes ? I thought I should ask
> for some advice before attempting measurements.
> 
> Cheers
> Michael
> 
> ___
> time-nuts mailing list -- time-nuts@lists.febo.com
> To unsubscribe, go to 
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Re: [time-nuts] Vibration isolation of quartz oscillators

[Poul-Henning Kamp]

Michael Wouters writes:

> In their former life they were part of the frequency synthesis chains
> for H-masers and they hung vertically from a rubber suspension that was
> presumably intended to provide vibration isolation. Unfortunately, the
> person responsible for this has long since retired so is no longer
> around to ask questions of.

Make sure that you orient the OCXO so it is least sensitive to acceleration
along the vertical axis.

You find this by flipping the OCXO upside/down in various orientations
while measuring the frequency shift.

Notice that in general the minimum sensitivity is not guaranteed to
correspond to any of X/Y/Z.

Check if Oscilloquartz have documented the optimal orientation.

-- 
Poul-Henning Kamp   | UNIX since Zilog Zeus 3.20
p...@freebsd.org | TCP/IP since RFC 956
FreeBSD committer   | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.

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Re: [time-nuts] Vibration isolation of quartz oscillators

[Tim Shoppa]

Damping at time constants of a fraction of second or longer can be done with 
shock absorbers which are usually some form of dashpots filled with viscous 
fluid or gas.

In the industry I work in we often use airbag suspensions up to time constants 
of several seconds.

I might guess that most vibrations in a lab you would want to eliminate would 
be fans humming in the same rack or folks opening and closing doors. These 
would be vibrations that are in the acoustic range.
I’m thinking the original rubber mounts were intended for this class of 
vibration dampening.

Tim N3QE

> 
> -Original Message-
> From: time-nuts [mailto:time-nuts-boun...@lists.febo.com] On Behalf Of
> Michael Wouters
> Sent: Saturday, June 27, 2020 08:03
> To: Discussion of precise time and frequency measurement
> Subject: [time-nuts] Vibration isolation of quartz oscillators
> 
> I have three Oscilloquartz 8607-Bs that I'm rehousing.
> 
> In their former life they were part of the frequency synthesis chains
> for H-masers and they hung vertically from a rubber suspension that was
> presumably intended to provide vibration isolation. Unfortunately, the
> person responsible for this has long since retired so is no longer
> around to ask questions of.
> 
> In the experiment I will be averaging over  100 s, which suggests to
> me that very low frequencies are what I need to filter out (if at
> all), and I am skeptical that the rubber will do this. Space is tight
> so I am wondering
> whether I should simply ditch the isolation.
> 
> What do other people do with their quartzes ? I thought I should ask
> for some advice before attempting measurements.
> 
> Cheers
> Michael
> 
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Re: [time-nuts] Vibration isolation of quartz oscillators

[Mike Garvey via time-nuts]

You could make some reasonable assumptions about vibration levels and
g-sensitivity and calculate the effect on ADEV.  This would let you know if
you're in the ballpark for your requirements.  
Also, Lord makes vibration isolators that address topics like damping and
they are designed to do it in minimalist space.  Likely not to be able to
get much isolation at 100s without the rubber suspensions, I suspect.  You
might also look at the work at NIST on the trapped ion work where they hung
(search Jim Bergquist) local oscillators from surgical tubing.

Mike

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@lists.febo.com] On Behalf Of
Michael Wouters
Sent: Saturday, June 27, 2020 08:03
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] Vibration isolation of quartz oscillators

I have three Oscilloquartz 8607-Bs that I'm rehousing.

In their former life they were part of the frequency synthesis chains
for H-masers and they hung vertically from a rubber suspension that was
presumably intended to provide vibration isolation. Unfortunately, the
person responsible for this has long since retired so is no longer
around to ask questions of.

In the experiment I will be averaging over  100 s, which suggests to
me that very low frequencies are what I need to filter out (if at
all), and I am skeptical that the rubber will do this. Space is tight
so I am wondering
whether I should simply ditch the isolation.

What do other people do with their quartzes ? I thought I should ask
for some advice before attempting measurements.

Cheers
Michael

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Re: [time-nuts] Vibration isolation of quartz oscillators

[Gerhard Hoffmann]

Am 27.06.20 um 14:02 schrieb Michael Wouters:


What do other people do with their quartzes ? I thought I should ask
for some advice before attempting measurements.


A sand box? Literally? Some bags filled with sand really helped

with my turntable. Make sure that it stays in the bags.


Gerhard




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[time-nuts] Vibration isolation of quartz oscillators

[Michael Wouters]

I have three Oscilloquartz 8607-Bs that I'm rehousing.

In their former life they were part of the frequency synthesis chains
for H-masers and they hung vertically from a rubber suspension that was
presumably intended to provide vibration isolation. Unfortunately, the
person responsible for this has long since retired so is no longer
around to ask questions of.

In the experiment I will be averaging over  100 s, which suggests to
me that very low frequencies are what I need to filter out (if at
all), and I am skeptical that the rubber will do this. Space is tight
so I am wondering
whether I should simply ditch the isolation.

What do other people do with their quartzes ? I thought I should ask
for some advice before attempting measurements.

Cheers
Michael

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