Bruce Griffiths wrote:
Bernd T-Online wrote:
Bi-convex contours are more difficult to manufacture, as it is required
that the symmetry axis of the upper and lower contour must coincide.
Also other parameters become worse. For the BVA the manufacturability
would also be much worse as it
Chuck Harris wrote:
Bruce Griffiths wrote:
Bernd T-Online wrote:
Bi-convex contours are more difficult to manufacture, as it is required
that the symmetry axis of the upper and lower contour must coincide.
Also other parameters become worse. For the BVA the manufacturability
BTW: I proudly own a HP2801A plus two crystal sensor elements. However I
cannot connect them to the instrument, because the 2801A has a special
connector for it. It looks like a smaller version of a BNC connector,
but the bayonet has three nipples instead of two. Does anyone on the
list
Jeff Mock wrote:
How does crystal aging look on a graph of temp versus frequency
What does this graph look like as a crystal ages? Does the optimal
operating temperature change over time, that is, does the graph tend to
move left and right, or does aging tend to move the graph
In message [EMAIL PROTECTED], Bernd T-Online writes:
Jeff Mock wrote:
I can confirm Rick's statement, that there is no noticable effect of
aging on the turnover temperature (TOT).
You got me wondering: How is the TOT determined ? Is it per unit
or is it per batch ? How precisely does an OCXO
Poul-Henning Kamp wrote:
You got me wondering: How is the TOT determined ? Is it per unit
or is it per batch ? How precisely does an OCXO hold the temperature
on the TOT ?
For crystals used in precision OCXO the TOT is measured and recorded per
unit.
There are two main methods: passive and
Bernd T-Online [EMAIL PROTECTED] wrote:
I can confirm Rick's statement, that there is no noticable effect of
aging on the turnover temperature (TOT).
Looking at it from physics standpoint, frequncy aging is mainly caused
by minor changes of vibrating mass and/or by changes in elastic
Tim Shoppa escribió:
For a while, didn't HP sell temperature probes which were in fact
quartz crystals? Oscillation frequency was converted by some simple
electronics to a temperature, and at the time (60's?) they were
exquisitely convenient for measuring way better than a tenth of a
degree.
Javier [EMAIL PROTECTED] wrote:
Tim Shoppa escribi?:
For a while, didn't HP sell temperature probes which were in fact
quartz crystals? Oscillation frequency was converted by some simple
electronics to a temperature, and at the time (60's?) they were
exquisitely convenient for measuring
Tim Shoppa wrote:
For a while, didn't HP sell temperature probes which were in fact
quartz crystals? Oscillation frequency was converted by some simple
electronics to a temperature, and at the time (60's?) they were
exquisitely convenient for measuring way better than a tenth of a
degree.
Javier wrote:
Anyway, a 10544 oscillator has a cold
offset that can easily be of 1000Hz, so if at 80 deg. C the offset is
zero, and at 25 deg. C the offset is 1000Hz, you easily have a rough
15Hz/deg C average tempco in that range - and the aging drift for this
oscillator is quite less
DK1AG wrote:
... the 2801A has a special
connector for it. It looks like a smaller version of a BNC connector,
but the bayonet has three nipples instead of two. Does anyone on the
list know what kind of connector that is and where to get the
counterpart (plug)?
Regards
Bernd
DK1AG
Bernd,
may
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Bernd T-Online
Sent: Sunday, December 09, 2007 8:44 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
Not the best
-Online [EMAIL PROTECTED]
To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Sent: Sunday, December 09, 2007 2:21 PM
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
Tim Shoppa wrote:
For a while, didn't HP sell temperature probes which were in fact
Yes, but that doesn't account for this part of his request
(emphasis added):
It looks like a *smaller* version of a BNC connector,
but the bayonet has three nipples instead of two.
-Chuck Harris
Alan Melia wrote:
Berndt I believe you are describing a Triax connector I found them through
Marco IK1ODO wrote:
may you send me a picture of the connector?
Direct email ik1odo at spin-it.com
Thanks, Marco. I have the unit in my QRL lab, so I can take a photo only
by tomorrow.
Regards
Bernd
DK1AG
___
time-nuts mailing list --
Yes, I know... I was only exposing it as an example of how the
temperature coefficient can be quite higher compared with the aging
effect even if the quartz crystal is not intended to be used as a
temperature sensor :)
Regards,
Javier
Bernd T-Online escribió:
Javier wrote:
Anyway, a
At 17.58 09/12/2007, Bernd wrote:
Thanks, Marco. I have the unit in my QRL lab, so I can take a photo only
by tomorrow.
Ok, good. There are triax connectors with three and two bayonets
around - ask Keithley... they have used both types.
Or it may be something else, HI.
73 - Marco IK1ODO /
Hal Murray wrote:
Why is the top domed? I assume flat would be easier to manufacture.
Why is it not symmetrical? If the top is domed, why not the bottom too?
For a plano-parallel qaurtz resonator the diameter must be at least 60
times larger than the thickness, otherwise the vibration
Bernd T-Online wrote:
Hal Murray wrote:
Why is the top domed? I assume flat would be easier to manufacture.
Why is it not symmetrical? If the top is domed, why not the bottom too?
For a plano-parallel qaurtz resonator the diameter must be at least 60
times larger than the
From: Bernd T-Online [EMAIL PROTECTED]
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
Date: Sat, 08 Dec 2007 09:27:28 +0100
Message-ID: [EMAIL PROTECTED]
Hal Murray wrote:
Why is the top domed? I assume flat would be easier to manufacture.
Why is it not symmetrical
Bernd T-Online wrote:
Hal Murray wrote:
Why is the top domed? I assume flat would be easier to manufacture.
Why is it not symmetrical? If the top is domed, why not the bottom too?
For a plano-parallel qaurtz resonator the diameter must be at least 60
times larger than the
Hal Murray wrote:
[EMAIL PROTECTED] said:
The key points which yield the BVA's improved aging are, that - the
whole resonator package is made from quartz, consisting of the
resonationg quartz plate in the middle section and the two mounting
sealing plaates on top and bottem - you may
[EMAIL PROTECTED] said:
The key points which yield the BVA's improved aging are, that - the
whole resonator package is made from quartz, consisting of the
resonationg quartz plate in the middle section and the two mounting
sealing plaates on top and bottem - you may call it a Hamburger
Thanks for the description, it is very interesting. I have a follow up
question if you don't mind.
How does crystal aging look on a graph of temp versus frequency. This
graph has some temperature point where the slope of frequency variation
goes to zero and the crystal is quite stable around
We did a lot of characterization of crystal temp
vs freq in the E1938 development and never observed
any aging of these curves. Even on green crystals
with zero run time.
Rick Karlquist N6RK
Jeff Mock wrote:
Thanks for the description, it is very interesting. I have a follow up
question if
Hello, All--
In doing some reading to educate myself on the relative
short and long-term stability characteristics of the best
grade quartz resonators, I find that BVA cut resonators
are on the leading edge of quartz crystal technology.
I have found out how a BVA resonator is fabricated, but
I
Michael Baker wrote:
I have found out how a BVA resonator is fabricated, but
I have not discovered what the acronym BVA stands for.
I suspect that the B in BVA may refer to Raymond Besson
the discoverer of the BVA quartz resonator, but I
have not been able to confirm that.
Can anyone on
@febo.com
Sent: Friday, December 07, 2007 11:20 AM
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
Michael Baker wrote:
I have found out how a BVA resonator is fabricated, but
I have not discovered what the acronym BVA stands
@febo.com; [EMAIL PROTECTED]
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
From: Richard (Rick) Karlquist [EMAIL PROTECTED]
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
Date: Fri, 07 Dec 2007 17:28:15 -0800
Message-ID: [EMAIL PROTECTED]
Rick
Coincidentally, I just learned today that the
E1983A is still being made by an OEM called
Scotts Valley Magnetics.
Rick Karlquist N6RK
Magnus Danielson wrote:
Is the E1938 commercially available? If not, is there a followup?
Cheers,
Magnus
07, 2007 5:52 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
Having low aging is nice, but the real problem is frequency
jumps. Do we know that they are the best in that respect?
If a crystal can jump 1E-10
Didier Juges wrote:
Maybe the cut is simply a smoke screen and the outstanding performance
is actually due to other process detail(s) not disclosed?
There's quite a bit of guff on the Oscilloquartz website - especially
if you find your way to the OXCO 8607-B datasheet (pdf).
I'm not
From: Didier Juges [EMAIL PROTECTED]
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
Date: Fri, 7 Dec 2007 17:17:59 -0600
Message-ID: [EMAIL PROTECTED]
I am not aware of other crystal oscillators with better performance, so
either I am missing something (the more likely
Try:
Boîtier à Vieillissement Amélioré
John WA4WDL
- Original Message -
From: John Ackermann N8UR [EMAIL PROTECTED]
To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Sent: Friday, December 07, 2007 11:20 AM
Subject: Re: [time-nuts] Super stable BVA Quartz
Boîtier à Vieillissement Amélioré
This is another version,
Enrico
Enrico Rubiola
professor of electronics
web:http://rubiola.org
e-mail: [EMAIL PROTECTED]
FEMTO-ST Institute
32 av. de l'Observatoire
25044 Besancon, FRANCE
voice: +33(0)381.853940 (E.Rubiola)
voice: +33(0)381.853999
measurement
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
Reminds me of the SC cut crystal.
It either means Stress Compensated or Santa Clara, where
it was discovered :-)
The BVA has been around for a long time and you would think
that if there was really something
From: Richard (Rick) Karlquist [EMAIL PROTECTED]
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
Date: Fri, 07 Dec 2007 17:28:15 -0800
Message-ID: [EMAIL PROTECTED]
Rick,
Coincidentally, I just learned today that the
E1983A is still being made by an OEM called
Scotts
and frequency measurement
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
Having low aging is nice, but the real problem is frequency
jumps. Do we know that they are the best in that respect?
If a crystal can jump 1E-10, then that represents 10 days of
aging all at once
Brian Styles said the following on 12/07/2007 07:15 PM:
There's quite a bit of guff on the Oscilloquartz website - especially
if you find your way to the OXCO 8607-B datasheet (pdf).
[ . . . ]
They've made over 10,000 of them. Anyone know what they're charging...?
Very rough numbers, but
stable BVA Quartz resonators... BVA??
Reminds me of the SC cut crystal.
It either means Stress Compensated or Santa Clara, where
it was discovered :-)
The BVA has been around for a long time and you would think
that if there was really something to it, everybody would be
making them
Reminds me of the SC cut crystal.
It either means Stress Compensated or Santa Clara,
where it was discovered :-)
The BVA has been around for a long time and you
would think that if there was really something to
it, everybody would be making them. Of course, they
are very difficult to make.
Rick
John Ackermann N8UR wrote:
The option -008, ... is about $14K. I'm told the yield
of those is about a dozen per year, and the lead time to get one is
around six months.
Hmm, not quite long enough to save up, then!
Changing the subject slightly, does anyone know the Thomson-CSF
PMT P5-1E ?
PROTECTED]
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
From: Richard (Rick) Karlquist [EMAIL PROTECTED]
Subject: Re: [time-nuts] Super stable BVA Quartz resonators... BVA??
Date: Fri, 07 Dec 2007 17:28:15 -0800
Message-ID: [EMAIL PROTECTED]
Rick
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