Re: [time-nuts] Non electrical time-nuttery

[Don Latham]

not hard to visualize.  If done that way, perhaps the two rods/tubes and the 
bob should be stress relieved by liquid nitrogen treatment. Seems to work 
for rifle barrels (one of my other time absorbers)

Don

- Original Message - 
From: "Lux, Jim (337C)" 
To: "Discussion of precise time and frequency measurement" 


Sent: Tuesday, January 12, 2010 5:14 AM
Subject: Re: [time-nuts] Non electrical time-nuttery





BTW, Invar has a really low tempcoefficient, but tends to random
shifts in its structure, yielding to abrupt length changes. Can't
have everything, I suppose...




That's what my friend trying to build the 1ppm pendulum found.  He found
that the standard technique is to build the pendulum out of two metals 
with

different CTE, arranged so that as the temperature changes, the center of
mass of the pendulum stays the same.

Imagine the long shaft of, say, 1 meter, with a CTE of 10 ppm/degree. You
support the bob with a sleeve attached at the bottom of the main shaft of
30cm with a CTE of 30 ppm material (so the bob sits at 70cm from the 
pivot).

As the temperature rises, the main shaft gets longer, but so does the
sleeve, so it pushes the bob back to the proper location.   (Wow, is this
difficult to describe in words)


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[time-nuts] Analog Devices precision voltage source

[Michael Baker]

Hello, TimeNutters--

I used the Analog Devices AD588 chip

> http://www.analog.com/static/imported-files/data_sheets/AD588.pdf <

to build a precision current reference for an older
model HP-628B clamp-on current meter.

I used the precision 10VDC to feed a 0.1% 1K resister for
a 10mA reference.  I brought a loop of wire in series
with the 10K resistor out to the front panel for access
by the probe.  The meter's full-scale meter ranges are:
1mA -  3mA - 10mA - 30mA - 100mA - 300mA - 1A - 10A

The HP628B clamp-on current meter has been a very useful
item on my work bench and the precision 10mA current reference
to check the meter calibration has been very handy.

Mike Baker

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Re: [time-nuts] Characterization of Oscillator w/ HP5345a

[jmfranke]

Yes you do, just read the hands.  The clock is precisely right at the 
displayed time..


John  WA4WDL

--
From: "Jean-Louis Oneto" 
Sent: Tuesday, January 12, 2010 9:17 PM
To: ; "Discussion of precise time and frequency measurement" 


Subject: Re: [time-nuts] Characterization of Oscillator w/ HP5345a


Yes, but the only problem is that you never know _when_ ;-}
Cheers,
Jean-Louis
- Original Message - 
From: "J. Forster" 
To: "Discussion of precise time and frequency measurement" 


Sent: Wednesday, January 13, 2010 2:04 AM
Subject: Re: [time-nuts] Characterization of Oscillator w/ HP5345a



The one that does not run at all is PRECISELY correct twice a day.

-John

=



paul swed wrote:

The more you know, the more you don't actually know.
Whats the saying?
A man with one watch knows what time it is. The man with three never
does.


 From an old film:

Q: Why do you have three watches?
A: Well, one runs slow, one runs quick and the third one doesn't run at
all.

This is why a man with three clocks does not know what time it is.

Cheers,
Magnus




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Re: [time-nuts] Characterization of Oscillator w/ HP5345a

[Jean-Louis Oneto]

Yes, but the only problem is that you never know _when_ ;-}
Cheers,
Jean-Louis
- Original Message - 
From: "J. Forster" 
To: "Discussion of precise time and frequency measurement" 


Sent: Wednesday, January 13, 2010 2:04 AM
Subject: Re: [time-nuts] Characterization of Oscillator w/ HP5345a



The one that does not run at all is PRECISELY correct twice a day.

-John

=



paul swed wrote:

The more you know, the more you don't actually know.
Whats the saying?
A man with one watch knows what time it is. The man with three never
does.


 From an old film:

Q: Why do you have three watches?
A: Well, one runs slow, one runs quick and the third one doesn't run at
all.

This is why a man with three clocks does not know what time it is.

Cheers,
Magnus




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Re: [time-nuts] Characterization of Oscillator w/ HP5345a

[J. Forster]

The one that does not run at all is PRECISELY correct twice a day.

-John

=


> paul swed wrote:
>> The more you know, the more you don't actually know.
>> Whats the saying?
>> A man with one watch knows what time it is. The man with three never
>> does.
>
>  From an old film:
>
> Q: Why do you have three watches?
> A: Well, one runs slow, one runs quick and the third one doesn't run at
> all.
>
> This is why a man with three clocks does not know what time it is.
>
> Cheers,
> Magnus



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Re: [time-nuts] I think I've become a Volt nut too.

[Magnus Danielson]

Bob Camp wrote:

Hi

For open box pendulums, the air swishing around in the cave should be very effective at locking every single one of them up. 


For something like a vacuum enclosed clock you would need lock modes that are a 
bit more crazy.


Vacuum enclosure still allows acoustical coupling through the support 
mechanics. Consider a speaker element, it pushes a bit of air away along 
with push its cone in that direction. However, the force has a counter 
fource to the underlying ground. While the movement is smaller, due to 
its higher acoustical impedance, it is still there. Similar for a 
pendulum, as it swings, the support mecanics feels a shift in force with 
the rate of the swing, so counter-acting force is need for not moving 
around. Maybe the best illustration would be the placement of a pendulum 
on top of a piece of ice over wet ice.


So, by saying acoustical, I by no means imply the waves in air.

Cheers,
Magnus

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Re: [time-nuts] Characterization of Oscillator w/ HP5345a

[Magnus Danielson]

paul swed wrote:

The more you know, the more you don't actually know.
Whats the saying?
A man with one watch knows what time it is. The man with three never does.


From an old film:

Q: Why do you have three watches?
A: Well, one runs slow, one runs quick and the third one doesn't run at all.

This is why a man with three clocks does not know what time it is.

Cheers,
Magnus

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Re: [time-nuts] I think I've become a Volt nut too.

[Magnus Danielson]

Hal Murray wrote:

a...@comcast.net said:

It is not impossible that for a sample of 100,000 secondary
standards, that the errors would be all be off in the same  direction,
compared to the standard's value.



Now, granted, this would be a small probability indeed.  But it  is
possible to toss a coin fifty times and have fifty "heads".  The smart
bet is that it won't. 


You need to consider systematic errors.

50 heads is simple if you are using a 2 headed coin.  Yes, that's an extreme 
example.


Consider lead-head and aluminium-back-sided coins. Systematic bias.
Consider that the same coin is used for many tosses, the lead would wear 
 off over time, so you have an aging mechanism which shifts the statistics.


But consider 100,000 pendulums that are all right-on and then the temperature 
changes.


Temperature gradients always occur from one end of the cave?

Cheers,
Magnus

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Re: [time-nuts] I think I've become a Volt nut too.

[Magnus Danielson]

Mike Naruta AA8K wrote:


Sure Chuck.  What I was talking about was a part of statistics that we 
in our gnat-hair-splitting compulsive group may forget about.


Let's assume that our 100,000 standards were carefully calibrated 
against THE standard.  There is a small amount of error in the 
calibration process.  Let us even assume that the error in the 
calibration process is normally distributed.


It is not impossible that for a sample of 100,000 secondary standards, 
that the errors would be all be off in the same direction, compared to 
the standard's value.


Now, granted, this would be a small probability indeed.  But it is 
possible to toss a coin fifty times and have fifty "heads". The smart 
bet is that it won't.


Well, if the distribution of these is only random and of benign 
randomness like gaussian noise.


If you have an aging mechanism for instance, over time this huge set 
would drift in that direction and that would produce a moving average 
value...


The rate of calibration to a primary standard would be one of the 
parameters needed to set the limit of drift.


So, systematic drift is not canceled by large number statistics. It just 
doest not obey the underlying assumption. Long-term noise of clocks 
obery the f^-3 noise which does not converge nicely and statistical 
measures needs to be adapted to provide reasnoble measures. This is why 
we have ADEV and friends.


Again, this is why you need to separate stability with reproducability 
aspects.


Cheers,
Magnus

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[time-nuts] OT Sorta

[J. Forster]

World Clock:



-John

==


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[time-nuts] New GPS Configuration: 24+3=Win/Win

[John Allen]

Three existing SVs to be moved to provide better coverage - details -

 

http://www.gpsworld.com/gnss-system/gps-modernization/new-gps-configuration-
243winwin-9369

 

 

John, K1AE

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Re: [time-nuts] I think I've become a Volt nut too.

[Bob Camp]

Hi

For open box pendulums, the air swishing around in the cave should be very 
effective at locking every single one of them up. 

For something like a vacuum enclosed clock you would need lock modes that are a 
bit more crazy.

Bob


On Jan 12, 2010, at 5:53 PM, Magnus Danielson wrote:

> Bill Hawkins wrote:
>> I'm picturing 100,000 pendula in a cave, all gravity locked to
>> their neighbors. (How small would they have to be to fit into
>> the main cave at Carlsbad Caverns, New Mexico?)
> 
> Gravity-lock? Wouldn't just the ordinary sound-waves be sufficient?
> 
> With a pendulum there will be mechanical bending and torsion as it swings 
> here and there... here and there... far more likely than the gravity shift of 
> the swings.
> 
> Regardless, even for well balanced, counter-swinging and whatever, putting 
> distance between two clocks will reduce both acoustical and gravity coupling 
> between them. Acoustical damping adapted to the pendulum rate would also 
> help, both as a transmitter and as a receiver, just as with any EMC case.
> 
> Cheers,
> Magnus
> 
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Re: [time-nuts] I think I've become a Volt nut too.

[Magnus Danielson]

Bill Hawkins wrote:

I'm picturing 100,000 pendula in a cave, all gravity locked to
their neighbors. (How small would they have to be to fit into
the main cave at Carlsbad Caverns, New Mexico?)


Gravity-lock? Wouldn't just the ordinary sound-waves be sufficient?

With a pendulum there will be mechanical bending and torsion as it 
swings here and there... here and there... far more likely than the 
gravity shift of the swings.


Regardless, even for well balanced, counter-swinging and whatever, 
putting distance between two clocks will reduce both acoustical and 
gravity coupling between them. Acoustical damping adapted to the 
pendulum rate would also help, both as a transmitter and as a receiver, 
just as with any EMC case.


Cheers,
Magnus

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[time-nuts] Lady Heather Software

[Mark Sims]

'486?  Gee,  even I don't live that far into the stone age...   

I'm rather surprised that the program works at that speed...  I've heard rumors 
that it is a hideously inefficient hog of system resources that needs at least 
a full core on a 3 GHz processor ;-)  (I know it runs just fine on a 100 Mhz 
Fujitsu Milan laptop with a Pentium processor)

I suspect that at 66,000 seconds and then every 33,000 seconds it will become 
rather sluggish for a while as it recalculates all the adev values from 
scratch...



BTW,  Compaq does have a lot of drivers available for ancient machines...
---
The computer is an old 486 Compaq I use for radio Programming and as
such, finding updates for the Video Drivers may be a problem !! 
  
_
Hotmail: Trusted email with powerful SPAM protection.
http://clk.atdmt.com/GBL/go/196390707/direct/01/
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Re: [time-nuts] T-Bolt Question

[Richard W. Solomon]

Sorry, fat fingers !!


-Original Message-
>From: "Richard W. Solomon" 
>Sent: Jan 12, 2010 3:20 PM
>To: time-nuts@febo.com
>Subject: [time-nuts] E-Bolt Question
>
>I am in T-Bolt Monitor software. The "Saved Position" is
>Yellow. How do I get the T-Bolt to save the survey results ?
>
>Thanks, Dick, W1KSZ
>
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Re: [time-nuts] Lady Heather Software

[Richard W. Solomon]

Thanks, that works a lot better. Part of the bottom seems cut off,
but I can live with that.
The computer is an old 486 Compaq I use for radio Programming and as
such, finding updates for the Video Drivers may be a problem !!

73, Dick, W1KSZ


-Original Message-
>From: John Miles 
>Sent: Jan 12, 2010 1:37 PM
>To: Discussion of precise time and frequency measurement 
>Subject: Re: [time-nuts] Lady Heather Software
>
>That normally means you're trying to run it at a fullscreen resolution your
>video card/monitor doesn't support.  Try the /vs /f combination to see if a
>lower resolution will work?  Otherwise, you may need to update the video
>drivers on the machine.
>
>-- john, KE5FX
>
>> -Original Message-
>> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on
>> Behalf Of Richard W. Solomon
>> Sent: Tuesday, January 12, 2010 10:14 AM
>> To: Discussion of precise time and frequency measurement
>> Subject: Re: [time-nuts] Lady Heather Software
>>
>>
>> I installed Lady Heather but when I try to get a full screen version
>> I get two error messages and the program aborts:
>>
>> Set Display Mode Failed
>>
>> DirectDraw could not be initialized
>>
>> Any hints on what to try ?
>>
>> Putting a /f in the target line does not work.
>>
>> 73, Dick, W1KSZ
>>
>>
>>
>>
>>
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>>
>
>
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Re: [time-nuts] I think I've become a Volt nut too.

[Rex]

Were you guys around (about a year back, I think) when this reference 
was mentioned?

http://www.voltagestandard.com/

Seems like excellent price/performance to me. I see he has a more 
accurate, more expensive model too.



paul swed wrote:

Wow thats a nice chip indeed

On Tue, Jan 12, 2010 at 2:58 PM, Nic McLean  wrote:

  

Roy,
The standard is based on the Analog Devices AD588 chip.
http://www.analog.com/static/imported-files/data_sheets/AD588.pdf
You can buy the magazine article at
http://siliconchip.com.au/cms/A_111365/article.html
Regards,
Nic


Hi Nick
Is it possible to let us have the schematic/details of this SC Magazine
Voltage Reference project, thanks
Roy








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[time-nuts] E-Bolt Question

[Richard W. Solomon]

I am in T-Bolt Monitor software. The "Saved Position" is
Yellow. How do I get the T-Bolt to save the survey results ?

Thanks, Dick, W1KSZ

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Re: [time-nuts] AVAR calculation

[Tom Van Baak]

Second thought, look at the tau=1 to 10 s and you see that it first 
rises before the usual slope. This is the effect of averaging in the 
counter. I would suspect that a HP53132A is being used.


Magnus,

You're correct about averaging effects; for example, see:
http://www.leapsecond.com/pages/adev-avg/

But, I think in this case it's not the measurement system
that's causing it because I saw the same PRS10 hump:

http://www.leapsecond.com/museum/prs10/1sigma2.gif
http://www.leapsecond.com/museum/prs10/log16084v.gif
http://www.leapsecond.com/museum/prs10/

What we see then would appear to be a feature of the PRS10
itself and not  the measurement system. Since the PRS10 is
based on a quality SC-cut OCXO, this might be an artifact of
their blending the OCXO and Rb cell; i.e., it looks just like a
GPSDO PLL hump, only moved two decades to the left.

/tvb


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Re: [time-nuts] I think I've become a Volt nut too.

[Hal Murray]

b...@iaxs.net said:
> I'm picturing 100,000 pendula in a cave, all gravity locked to their
> neighbors. (How small would they have to be to fit into the main cave
> at Carlsbad Caverns, New Mexico?)

Wikipedia says:
  Big Room or The Hall of the Giants
  The largest chamber in Carlsbad Caverns, with a floor space of 33,210 m2 
(357,469 sq ft).

So that's 3 sq ft per clock.  Round up for all the other parts of the cave.  
Round down for the edges that aren't tall enough.

That's ignoring height.  You could also stack them on top of each other, at 
least in some places.


Tuxedo Park has a good story.

Loomis had 3 of the Shortt clocks.  They were down in a basement room dug out 
of bedrock.

He had to work hard to get them not to lock up.
  "He found that when he placed the clocks in the
  corners of an equilateral triangle, facing inward,
  the coupling was broken."



-- 
These are my opinions, not necessarily my employer's.  I hate spam.




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[time-nuts] I think I've become a Volt nut too.

[Dr. Frank Stellmach]

 True, but there is always a probability that they all happen to
 be off one way.



 Quite a small probability, but not impossible.



 Sorry for the disturbing thought.




In the case of the 732A, and the early 732B, this is in fact the case!


Fluke mentioned, that all the 732A and the early 732B containing the
Motorola reference had a systematic positive drift, whereas the later 732B, 
LTZ1000 based,
showed a negative drift.

Ref.: fluke.ae/comx/applications/deaver_msc01.pdf


Therefore, for an ensemble of references, it is important to have a very
good instant calibration

(referred to a Josephson effect based standard), plus a determination of
the annual drift rate by repeated

calibration. Only then, statistical improvement by an ensemble makes sense.


Btw.: Many artifact references cannot/define/  the VOLT:


Such a definition by Weston ensembles drifted apart 10ppm between the
different National Standard Institutes during the years.

Only the introduction of the 'Josephson-Volt' in 1970 lead to the
reproducibilty of the VOLT within 1e-9 worldwide.


But the VOLT still is uncertain by 1e-7 in the SI system..

Perhaps next year this will change by redefinition of the SI-System (h,
e, k, kg,..).


Frank


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Re: [time-nuts] Lady Heather Software

[John Miles]

That normally means you're trying to run it at a fullscreen resolution your
video card/monitor doesn't support.  Try the /vs /f combination to see if a
lower resolution will work?  Otherwise, you may need to update the video
drivers on the machine.

-- john, KE5FX

> -Original Message-
> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on
> Behalf Of Richard W. Solomon
> Sent: Tuesday, January 12, 2010 10:14 AM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] Lady Heather Software
>
>
> I installed Lady Heather but when I try to get a full screen version
> I get two error messages and the program aborts:
>
> Set Display Mode Failed
>
> DirectDraw could not be initialized
>
> Any hints on what to try ?
>
> Putting a /f in the target line does not work.
>
> 73, Dick, W1KSZ
>
>
>
>
>
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Re: [time-nuts] AVAR calculation

[Magnus Danielson]

Magnus Danielson wrote:

Filip Ozimek wrote:
I'm trying to calculate AVAR from collected data, but I would expect a 
different behavior of my DUT. Does anybody can calculate the AVAR for me?

Gate time was 1s, without any deadtime between measurements,
this is a file http://www.fuw.edu.pl/~fozimek/pomiar61-frep.txt
with collected data.


Would you care to elaborate on how this data was collected?

By the looks of things, if this is indeed frequency data, then it is 
interesting to note that data is in steps of 1/4000 Hz every second. For 
a 250 MHz oscillator having 4 ns period time, this amounts to a time 
resolution of 1 ps. A quick histogram displays that 115 bins is filled 
in what looks like Gaussian-like... but it is dragged out by the drift.


Few counters give such numbers, so I am curious. There are ways to 
improve frequency measures, but they tend to smooth over data in a 
fashion that you don't want for normal ADEV analysis. At the first look 
on the data, the source looks very quiet. The ADEV curves plotted looks 
more normal.


Second thought, look at the tau=1 to 10 s and you see that it first 
rises before the usual slope. This is the effect of averaging in the 
counter. I would suspect that a HP53132A is being used.


Cheers,
Magnus

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Re: [time-nuts] I think I've become a Volt nut too.

[paul swed]

Wow thats a nice chip indeed

On Tue, Jan 12, 2010 at 2:58 PM, Nic McLean  wrote:

> Roy,
> The standard is based on the Analog Devices AD588 chip.
> http://www.analog.com/static/imported-files/data_sheets/AD588.pdf
> You can buy the magazine article at
> http://siliconchip.com.au/cms/A_111365/article.html
> Regards,
> Nic
>
>
> Hi Nick
> Is it possible to let us have the schematic/details of this SC Magazine
> Voltage Reference project, thanks
> Roy
>
>
>
>
>
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Re: [time-nuts] I think I've become a Volt nut too.

[J. Forster]

Hmmm...  gravity locking. I wonder if you could actually power a torsion
pendulum that way?

-John

==




> I'm picturing 100,000 pendula in a cave, all gravity locked to
> their neighbors. (How small would they have to be to fit into
> the main cave at Carlsbad Caverns, New Mexico?)
>
> So, how much would the temperature gradient have to be to break
> the lock?
>
> Ah, maybe it isn't gravity, but the common floor support.
>
> What a great day for thought experiments.
>
> Bill Hawkins



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Re: [time-nuts] I think I've become a Volt nut too.

[Bill Hawkins]

I'm picturing 100,000 pendula in a cave, all gravity locked to
their neighbors. (How small would they have to be to fit into
the main cave at Carlsbad Caverns, New Mexico?)

So, how much would the temperature gradient have to be to break
the lock?

Ah, maybe it isn't gravity, but the common floor support.

What a great day for thought experiments.

Bill Hawkins


-Original Message-
From: Hal Murray
Sent: Tuesday, January 12, 2010 1:28 PM

But consider 100,000 pendulums that are all right-on and then the
temperature 
changes.


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Re: [time-nuts] I think I've become a Volt nut too.

[Nic McLean]

Roy,
The standard is based on the Analog Devices AD588 chip.
http://www.analog.com/static/imported-files/data_sheets/AD588.pdf
You can buy the magazine article at
http://siliconchip.com.au/cms/A_111365/article.html
Regards,
Nic


Hi Nick
Is it possible to let us have the schematic/details of this SC Magazine 
Voltage Reference project, thanks
Roy





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[time-nuts] I think I've become a Volt nut too.

[Dr. Frank Stellmach]

 Hi All,

 I have been a time nut for some time now. I think I've become a Volt nut
 too! I build the Silicon Chip magazine Voltage reference late last year but
 didn't have anything to compare it against so I bought a Fluke 732A DC
 reference standard.



 I there a group I can subscribe to that can help me with this?



 Can I coin the phrase; A man that has one DC Voltage standard knows how
 accurate his meter is, whereas a man with two standards is not quite sure!



 Regards,



 Nic



 VK2KXN VK5ZAT



 Hi Nic,

please goto febo.com/pipermail/volt-nuts; John Ackermann opened a parallel 
mailing list to time-nuts to have a distinct discussion platform.

I'm interested also, what kind of reference is used in the Silicon Chip 
magazine..is it LTZ1000 based?


A single volt-reference would be sufficient, if it is calibrated peridiocally, 
i.e. if its drift rate is determined during at least 5 calibrations or so.
In this case, a certainty of around 1ppm would be achievable.

A 2nd reference would be better for keeping a working standard at home while 
the other is out for calibration.
And an ensemble of 4 is good for averaging the VOLT below 1 ppm.

Frank





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Re: [time-nuts] Question about Firmware for EIP Counters

[J. Forster]

Try the EIP_Microwave Group on YahooGroups.

-John





> Is anyone on the list familiar with the firmware for EIP 578 or 548 series
> counters?  I have a favorite 578 counter, with power measuring  option,
> that I have owned for years.  All of this time I have wished it had  the
> Frequency Extension option.  Recently I bought a mechanically-damaged  578
> with
> the desired extended frequency range feature on eBay.  I removed  the
> optional
> RF parts and added them to my old counter.  I also  transferred the
> associated firmware PROM (U20) to my counter's A-105  microprocessor
> board, and
> added the jumper required to activate the feature on a  second board.  But
> the
> option failed to work.  By pressing buttons I  determined the cause was a
> firmware rather than RF problem.
>
> While my old firmware set of 5 PROMS was Version-B, the "parts"  counter
> had Version-D PROMS, even though it was not far removed in  serial number
> and
> bore the same CCN code.  So I transferred the remaining  Version-D PROMS
> to
> my counter and presto! the frequency extension option worked  great!
> However, before I could celebrate by closing the case, I realize  the
> prized power
> measurement feature no longer worked.  I tried  interchanging the first
> then last PROMs in the programming sequence, but this  just caused the
> microprocessor to lock-up.  I am left with the feeling  that the various
> firmware
> versions might correspond to the eight  permutations of the three options
> requiring microprocessor intervention (A to  D Converter, Power Meter, &
> Frequency Extension).  If this is the  case, my augmentation project seems
> doomed
> unless I can obtain a copy of  the appropriate firmware.  Has any list
> member
> had experience adding  options to the EIP counters of this family?   I
> have
> already  asked this question on the Microwave Reflector, but with no
> responses.
>
> Bruce Hunter, KG6OJI
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Re: [time-nuts] I think I've become a Volt nut too.

[Hal Murray]

a...@comcast.net said:
> It is not impossible that for a sample of 100,000 secondary
> standards, that the errors would be all be off in the same  direction,
> compared to the standard's value.

> Now, granted, this would be a small probability indeed.  But it  is
> possible to toss a coin fifty times and have fifty "heads".  The smart
> bet is that it won't. 

You need to consider systematic errors.

50 heads is simple if you are using a 2 headed coin.  Yes, that's an extreme 
example.

But consider 100,000 pendulums that are all right-on and then the temperature 
changes.



-- 
These are my opinions, not necessarily my employer's.  I hate spam.




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Re: [time-nuts] Lady Heather Software

[Richard W. Solomon]

I installed Lady Heather but when I try to get a full screen version 
I get two error messages and the program aborts:

Set Display Mode Failed

DirectDraw could not be initialized

Any hints on what to try ?

Putting a /f in the target line does not work.

73, Dick, W1KSZ





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Re: [time-nuts] Question about Firmware for EIP Counters

[Bruce Lane]

If you do happen to run across the image files for the EPROMs in
question, I would appreciate a copy of them for my FTP archive, so they
may be of help to others.

Thanks.


*** REPLY SEPARATOR  ***

On 12-Jan-10 at 12:54 brucekar...@aol.com wrote:

>Is anyone on the list familiar with the firmware for EIP 578 or 548
>series  
>counters?  I have a favorite 578 counter, with power measuring  option, 
>that I have owned for years.  All of this time I have wished it had  the

>Frequency Extension option.  Recently I bought a mechanically-damaged
578
>with 
>the desired extended frequency range feature on eBay.  I removed  the
>optional 
>RF parts and added them to my old counter.  I also  transferred the 
>associated firmware PROM (U20) to my counter's A-105  microprocessor
>board, and 
>added the jumper required to activate the feature on a  second board.
But
>the 
>option failed to work.  By pressing buttons I  determined the cause was
a 
>firmware rather than RF problem.   
> 
>While my old firmware set of 5 PROMS was Version-B, the "parts"  counter

>had Version-D PROMS, even though it was not far removed in  serial
number
>and 
>bore the same CCN code.  So I transferred the remaining  Version-D PROMS
>to 
>my counter and presto! the frequency extension option worked  great!  
>However, before I could celebrate by closing the case, I realize  the
>prized power 
>measurement feature no longer worked.  I tried  interchanging the first 
>then last PROMs in the programming sequence, but this  just caused the 
>microprocessor to lock-up.  I am left with the feeling  that the various
>firmware 
>versions might correspond to the eight  permutations of the three
options 
>requiring microprocessor intervention (A to  D Converter, Power Meter, &

>Frequency Extension).  If this is the  case, my augmentation project
seems
>doomed 
>unless I can obtain a copy of  the appropriate firmware.  Has any list
>member 
>had experience adding  options to the EIP counters of this family?   I
>have 
>already  asked this question on the Microwave Reflector, but with no 
>responses.
> 
>Bruce Hunter, KG6OJI
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>__ Information from ESET Smart Security, version of virus
>signature database 4765 (20100112) __
>
>The message was checked by ESET Smart Security.
>
>http://www.eset.com


Bruce Lane, Owner & Head Hardware Heavy,
Blue Feather Technologies (http://www.bluefeathertech.com)
Assoc. member, AZA & AAZK for many moons.
"Salvadore Dali's computer has surreal ports..."


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[time-nuts] Question about Firmware for EIP Counters

[brucekareen]

Is anyone on the list familiar with the firmware for EIP 578 or 548 series  
counters?  I have a favorite 578 counter, with power measuring  option, 
that I have owned for years.  All of this time I have wished it had  the 
Frequency Extension option.  Recently I bought a mechanically-damaged  578 with 
the desired extended frequency range feature on eBay.  I removed  the optional 
RF parts and added them to my old counter.  I also  transferred the 
associated firmware PROM (U20) to my counter's A-105  microprocessor board, and 
added the jumper required to activate the feature on a  second board.  But the 
option failed to work.  By pressing buttons I  determined the cause was a 
firmware rather than RF problem.   
 
While my old firmware set of 5 PROMS was Version-B, the "parts"  counter 
had Version-D PROMS, even though it was not far removed in  serial number and 
bore the same CCN code.  So I transferred the remaining  Version-D PROMS to 
my counter and presto! the frequency extension option worked  great!  
However, before I could celebrate by closing the case, I realize  the prized 
power 
measurement feature no longer worked.  I tried  interchanging the first 
then last PROMs in the programming sequence, but this  just caused the 
microprocessor to lock-up.  I am left with the feeling  that the various 
firmware 
versions might correspond to the eight  permutations of the three options 
requiring microprocessor intervention (A to  D Converter, Power Meter, & 
Frequency Extension).  If this is the  case, my augmentation project seems 
doomed 
unless I can obtain a copy of  the appropriate firmware.  Has any list member 
had experience adding  options to the EIP counters of this family?   I have 
already  asked this question on the Microwave Reflector, but with no 
responses.
 
Bruce Hunter, KG6OJI
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Re: [time-nuts] Lady Heather Software

[Peter Vince]

Latest official version (2.0) can be downloaded via

http://www.thegleam.com/ke5fx/heather/readme.htm

The 3.0 beta version is at

http://www.ke5fx.com/heather/beta.exe




2010/1/12 Richard W. Solomon :
> Where will I find the latest version ?
>
> Thanks, Dick, W1KSZ
>
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[time-nuts] Lady Heather Software

[Richard W. Solomon]

Where will I find the latest version ?

Thanks, Dick, W1KSZ

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Re: [time-nuts] I think I've become a Volt nut too.

[paul swed]

There are numbers of low power references
I like to take 2-3 of these put them together with 3 resistors to average
the diff.

On Tue, Jan 12, 2010 at 11:26 AM, Richard W. Solomon wrote:

> Maxim has a number of voltage reference chips. I built
> one using a 2.5 vdc output.
>
> 73, Dick, W1KSZ
>
>
> -Original Message-
> >From: Roy Phillips 
> >Sent: Jan 12, 2010 3:19 AM
> >To: Discussion of precise time and frequency measurement <
> time-nuts@febo.com>
> >Subject: Re: [time-nuts] I think I've become a Volt nut too.
> >
> >Hi Nick
> >Is it possible to let us have the schematic/details of this SC Magazine
> >Voltage Reference project, thanks
> >Roy
> >
> >
> >--
> >From: "Nic McLean" 
> >Sent: Tuesday, January 12, 2010 3:12 AM
> >To: "'Discussion of precise time and frequency measurement'"
> >
> >Subject: [time-nuts] I think I've become a Volt nut too.
> >
> >> Hi All,
> >>
> >> I have been a time nut for some time now. I think I've become a Volt nut
> >> too! I build the Silicon Chip magazine Voltage reference late last year
> >> but
> >> didn't have anything to compare it against so I bought a Fluke 732A DC
> >> reference standard.
> >>
> >>
> >>
> >> I there a group I can subscribe to that can help me with this?
> >>
> >>
> >>
> >> Can I coin the phrase; A man that has one DC Voltage standard knows how
> >> accurate his meter is, whereas a man with two standards is not quite
> sure!
> >>
> >>
> >>
> >> Regards,
> >>
> >> Nic
> >>
> >> VK2KXN VK5ZAT
> >>
> >> ___
> >> time-nuts mailing list -- time-nuts@febo.com
> >> To unsubscribe, go to
> >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> >> and follow the instructions there.
> >>
> >
> >
> >___
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Re: [time-nuts] I think I've become a Volt nut too.

[Richard W. Solomon]

Maxim has a number of voltage reference chips. I built
one using a 2.5 vdc output.

73, Dick, W1KSZ


-Original Message-
>From: Roy Phillips 
>Sent: Jan 12, 2010 3:19 AM
>To: Discussion of precise time and frequency measurement 
>Subject: Re: [time-nuts] I think I've become a Volt nut too.
>
>Hi Nick
>Is it possible to let us have the schematic/details of this SC Magazine 
>Voltage Reference project, thanks
>Roy
>
>
>--
>From: "Nic McLean" 
>Sent: Tuesday, January 12, 2010 3:12 AM
>To: "'Discussion of precise time and frequency measurement'" 
>
>Subject: [time-nuts] I think I've become a Volt nut too.
>
>> Hi All,
>>
>> I have been a time nut for some time now. I think I've become a Volt nut
>> too! I build the Silicon Chip magazine Voltage reference late last year 
>> but
>> didn't have anything to compare it against so I bought a Fluke 732A DC
>> reference standard.
>>
>>
>>
>> I there a group I can subscribe to that can help me with this?
>>
>>
>>
>> Can I coin the phrase; A man that has one DC Voltage standard knows how
>> accurate his meter is, whereas a man with two standards is not quite sure!
>>
>>
>>
>> Regards,
>>
>> Nic
>>
>> VK2KXN VK5ZAT
>>
>> ___
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>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
>> 
>
>
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Re: [time-nuts] time-nuts Digest, Vol 66, Issue 55

[Chuck Harris]

Do a search on volt-nuts.



Volt-nuts is populated by many of the members
of time-nuts.

-Chuck

Dick Moore wrote:

Nic, many times volt-nut questions are posted here, including by me, and no one has 
ever said "get outta here, we're
TIME-NUTS."

I currently have two 732As, a Fluke 5440B, a couple of Datron 1082s, and not 
too long ago got an HP3458A and had it
cal'd by HP in Loveland. One thing I've discovered so far about the 732As is 
that you really only need one unless
you're a belt-and-suspender kind of guy. Either of mine reliably return to 
better than 0.1ppm of base from several
cold starts, given a warm-up of a day or so, so I've dispensed with the 
batteries completely. Over the last few
months, the two 732s track within 0.05ppm as measured by the 3458, which also 
tells me that the 3458 is pretty good
too.

I know of no other "volt-nut" sites, but others here may know of some -- I hope 
they do. I do have a web site of my
own, but I haven't yet set up a volt-nut blog -- I'm looking at the Phorum 
open-source software for another project,
and if I think the traffic won't be real high (how could it?) then I'll look 
into the possibility of hosting such a
thing. In the mean time, Volt On!!

Dic k Moore


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Re: [time-nuts] I think I've become a Volt nut too.

[Raj]

It is possible for 100k secondary standards average to be skewed if they were 
calibrated to the same primary standard. All the primary standards would have 
to different for the secondary average to be an real average.

Coin toss analogy would be slightly different if the coins were all different 
shapes and sizes.. but probably not!

>It is not impossible that for a sample of 100,000 secondary standards, that 
>the errors would be all be off in the same direction, compared to the 
>standard's value.
>
>Now, granted, this would be a small probability indeed.  But it is possible to 
>toss a coin fifty times and have fifty "heads". The smart bet is that it won't.
>

-- 
Raj, VU2ZAP
Bangalore, India. 


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Re: [time-nuts] I think I've become a Volt nut too.

[Mike Naruta AA8K]

Sure Chuck.  What I was talking about was a part of statistics 
that we in our gnat-hair-splitting compulsive group may forget 
about.


Let's assume that our 100,000 standards were carefully 
calibrated against THE standard.  There is a small amount of 
error in the calibration process.  Let us even assume that the 
error in the calibration process is normally distributed.


It is not impossible that for a sample of 100,000 secondary 
standards, that the errors would be all be off in the same 
direction, compared to the standard's value.


Now, granted, this would be a small probability indeed.  But it 
is possible to toss a coin fifty times and have fifty "heads". 
The smart bet is that it won't.




Chuck Harris wrote:

That will only be true of primary standards.  Secondary standards
must be calibrated to some "primary standard".  If all 100,000 of
your secondary standards were calibrated to the wrong value, they
will all have values that hover around that wrong value.

-Chuck Harris



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Re: [time-nuts] Non electrical time-nuttery

[Brooke Clarke]

Hi Tom:

One problem with adjusting the rate of a pendulum clock is that you 
don't want to stop it to make fine adjustments.  That's why the tray for 
the micro weights.  In the case of the Western Union Self Winding Clocks 
you can slow down the pendulum by dropping candle wax on the bob.

http://www.prc68.com/I/SWCC.shtml

Have Fun,

Brooke Clarke
http://www.PRC68.com


Tom Van Baak wrote:

How does the pressure change the frequency?


Assuming a fixed mechanical impulse, an increase in
pressure will result in a slight decrease in amplitude
due to the increased friction of the air. Then because
of circular error this will result in a very slight change
in period (by a few tens to hundreds of ppm). Thus
you can use pressure as a fine-adjustment of rate.

Equivalently, if one does not maintain the pressure to
some level of stability, it will affect the stability of the
amplitude which will affect the stability of the period
which will affect the timekeeping performance of the
clock. The exact numerical relationship among these
factors depends on the design of the clock.

So as you can imagine open-case pendulum clocks
make good barometers as well as thermometers. And
that's one reason why all the best pendulum clocks
make use of a sealed, low pressure, chamber.

That does raise an interesting issue.  How would you fine tune a 
pendulum?


Typically one adjusts the effective length by placing
micro-weights to slightly move the center of gravity
of the bob. Larger adjustments are made by raising
or lowering the bob itself with the rating nut.

These technique is also used for vacuum pendulum
clocks but one does not want to do it more than once
or twice.

/tvb


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[time-nuts] Eclipse alert - Call for VCO traces

[iov...@inwind.it]

Time-nuts,

many of you are routinely recording - or may easily do it - the 
trace 
of the control voltage of non-free-running crystal oscillators 

(disciplined by atomic resonance or GPS).

Once again I'm here asking you to 
keep an open eye during a solar 
eclipse, which will occur on January 15. 

My 
current opinion is that the eclipse couldn't affect atomic 
resonances at a 
measurable level for the state of the art, but could 
affect massive (as 
compared to atoms) pieces of vibrating matter. 

The control voltage trace 
tells us whether a crystal deviated, even in 
front of a constant rate of the 
whole clock. 

I recall (already mentioned in this list) that previous tests 
(Max 
Plank Institute) showed no deviations of atomic resonances, but we 
don't 
have info about control voltages, and that S.W.Zhou instead 
claimed to have 
observed deviations that indeed I believe were 
deviations of crystals not 
promptly steered.

During this eclipse a numerous team of researchers will be 
conducting 
sophisticated pendulum tests at the Maldives (latitude near to 
zero, 
no Foucault effect), and a number of US institutions, located in the 

anti-eclipse path, will provide gravimeter data. Elsewhere, Russia and 
Florida 
at least, torsion balance tests will be conducted. Just to mention 
what I'm 
aware of.

As far as I know, nobody will provide clock (I would say 
oscillator)  
data. Hence I' m asking this list to give a contribution. 

What 
I ask is to send me your control voltage data, possibly for the 
days 14-15-16 
January, and from preferred locations -but not only- in 
the eclipse or anti-
eclipse path, even penumbra or anti-penumbra. 

Googling "fred espenak" you 
will immediately find the data for the 
incoming eclipse. 

Thanks in advance.


Antonio I8IOV


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Re: [time-nuts] Non electrical time-nuttery

[Lux, Jim (337C)]

>> BTW, Invar has a really low tempcoefficient, but tends to random
>> shifts in its structure, yielding to abrupt length changes. Can't
>> have everything, I suppose...
>

That's what my friend trying to build the 1ppm pendulum found.  He found
that the standard technique is to build the pendulum out of two metals with
different CTE, arranged so that as the temperature changes, the center of
mass of the pendulum stays the same.

Imagine the long shaft of, say, 1 meter, with a CTE of 10 ppm/degree. You
support the bob with a sleeve attached at the bottom of the main shaft of
30cm with a CTE of 30 ppm material (so the bob sits at 70cm from the pivot).
As the temperature rises, the main shaft gets longer, but so does the
sleeve, so it pushes the bob back to the proper location.   (Wow, is this
difficult to describe in words)


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Re: [time-nuts] Non electrical time-nuttery

[Neville Michie]

These are both good books, in fact the best out there, but both have  
significant flaws.
For instance they cannot unequivocally accept that high Q is  
fundamental to good time keeping

in a clock.
They look at an un-sustained pendulum and say it only oscillates for  
10 minutes, so
obviously it cannot measure beyond that time. They fail to realise  
that in a clock,
losses are made good so the oscillator has infinite Q. And an  
oscillator with infinite Q

can define any length of time.

Any form of friction or loss is bad as it increases the amount of  
make-up energy
that must be supplied. That can only increase the possibility of  
frequency or phase drift.


There are two main barometric pressure effects. First is buoyancy,  
the pendulum losing
apparent weight by floatation in the air. The inertia stays the same,  
but the attraction to
the centre of the earth is decreased. That attraction is the  
restoring force.
The second effect is that the pendulum bob displaces a mass of air  
that sloshes around
the clock case. This air has momentum and adds slightly to the  
momentum of the pendulum.


The air will also cause the increase in damping that effects  
amplitude, and via circular error,
change the frequency, but this is a lesser effect or non-existent  
when electronic feedback
is used control amplitude. Only clock people think they can run an  
oscillator without

amplitude control.
In my experimental clock I control amplitude and use circular error  
to adjust timing.


You may have gathered that my time nut activities are directed to  
pendulum clocks,

in particular an improved pendulum.

Buoyancy can be neutralised in a suitably shaped compound pendulum.   
Consider a light

cylinder pivoted in the middle.
No matter how dense the medium it is in it will experience no torque.  
Put a weight in one end

and you have a buoyancy compensated pendulum.

Circular error is more difficult, but if you have a knife-edge  
suspension with a finite radius,
the circular curve crosses the cycloid (the curve of an isochronic  
pendulum) at a low amplitude,
 and like a quartz crystal at its thermal turnover, you have an  
amplitude where small changes

in amplitude have no effect on time.

Torsion pendulums are also sensitive to gravity. When you twist the  
suspension it gets slightly shorter.


The best mechanical timekeeper is probably the quartz crystal, it has  
stable mass, stable elasticity,
stable dimensions and very low damping losses. Put it in a vacuum,  
keep its temperature constant,

make good its losses  and you have a good clock.

cheers, Neville Michie




On 12/01/2010, at 7:41 PM, Don Latham wrote:

I'm not absolutely certain, Hal, but I think high Q has to do with  
the spectral purity of the source, but not necessarily with its  
long term stability, which depends on other design factors. I can  
only say about the damping that I dimly remember it in connection  
with the Shortt clocks but cannot remember where.
This track caused me to go into my stacks (I really thought I was  
free of the pendulum compulsion, but apparently 'taint so). There  
are two books i'd recommend:
Mathys, Robert J, "Accurate Clock Pendulums",Oxford University  
Press, NY, 2004, ISBN0 19 852971 6 (Hbk) ; this is a real bible  
about vertical pendula. Amazon lists this one, both used and new
And for a personal, very entertaining, refreshing, and thorough  
examination of pendulum clock building,
Woodward, Philip, "My own Right Time : An Exploration of Clockwork  
Design", Oxford University Press, NY, 1995, ISBN 0 19 856522 4 I  
really enjoyed this book! Amazon has this one both used and new.
If you get these used, you'll spend about $170, but you will avoid  
endless hours of fooling around. OTH if the fooling around amuses,  
then. . .
BTW, Invar has a really low tempcoefficient, but tends to random  
shifts in its structure, yielding to abrupt length changes. Can't  
have everything, I suppose...


Best to all,
Don Latham




- Original Message - From: "Hal Murray"  

To: "Discussion of precise time and frequency measurement" n...@febo.com>

Sent: Monday, January 11, 2010 8:04 PM
Subject: Re: [time-nuts] Non electrical time-nuttery




d...@montana.com said:

Also, according to some info I read on pendulum clocks, vacuum does
not work because some viscous drag is needed to damp the free
pendulum;


Why do I need damping?

I thought the general idea on oscillators was to get the highest Q  
(lowest
damping) that was reasonable.  But now that I think about it, I'm  
not sure

why.


--
These are my opinions, not necessarily my employer's.  I hate spam.




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Re: [time-nuts] I think I've become a Volt nut too.

[Roy Phillips]

Hi Nick
Is it possible to let us have the schematic/details of this SC Magazine 
Voltage Reference project, thanks

Roy


--
From: "Nic McLean" 
Sent: Tuesday, January 12, 2010 3:12 AM
To: "'Discussion of precise time and frequency measurement'" 


Subject: [time-nuts] I think I've become a Volt nut too.


Hi All,

I have been a time nut for some time now. I think I've become a Volt nut
too! I build the Silicon Chip magazine Voltage reference late last year 
but

didn't have anything to compare it against so I bought a Fluke 732A DC
reference standard.



I there a group I can subscribe to that can help me with this?



Can I coin the phrase; A man that has one DC Voltage standard knows how
accurate his meter is, whereas a man with two standards is not quite sure!



Regards,

Nic

VK2KXN VK5ZAT

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Re: [time-nuts] Non electrical time-nuttery

[Don Latham]

Ah, but a torsion pendulum is inescapably a kind of vertical pendulum as 
well?

Don
- Original Message - 
From: "J. Forster" 
To: "Discussion of precise time and frequency measurement" 


Sent: Monday, January 11, 2010 9:22 PM
Subject: Re: [time-nuts] Non electrical time-nuttery





namic...@gmail.com said:

The reason that I remember a hard vacuum is not used is because the
low pressure is used to rate the pendulum (fine tune) by slightly
increasing or decreasing, and in a hard vacuum metals tend to weld
together and oils evaporate so the mechanical bits seize up.


How does the pressure change the frequency?


I don't think it does.


Why are oils a problem?  I thought typical pendulums used a spring rather
than a bearing.


I think a torsion pendulum suspended by a fiber woul have no oil to be an
issue.

That does raise an interesting issue.  How would you fine tune a 
pendulum?


A back-and-forth pendulum is tuned by adjusting it's active length. If
it's suspended by a flat spring, you can adjust the spring length,
adjusting the period.

With a torsional pendulum you could also adjust the spring rate or the
wheel moment of inertia with symmetric radial screws.


If you can get close enough, then you can tweak things by varying the
amplitude, or temperature.


I don't think that's a good idea. With a back-and-forth pendulum amplitude
adjusts non-linearity. A good pendulum should be temp independent.


Big Ben is tuned by adding/removing a penny from the pendulum.
  http://en.wikipedia.org/wiki/Big_Ben  (search for penny)
That technique gets more interesting in a vacuum, but you might be able

to rig up something equivalent.

Effectively changing the pendulum length by moving the CG relative to the
pivot point.

-John

===


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Re: [time-nuts] I think I've become a Volt nut too.

[Don Latham]

No. You've already fallen in the rabbit hole.. The next thing is to begin 
your study of randomness.

HeHeHeHe...
Don
- Original Message - 
From: "Nic McLean" 
To: "'Discussion of precise time and frequency measurement'" 


Sent: Monday, January 11, 2010 8:12 PM
Subject: [time-nuts] I think I've become a Volt nut too.



Hi All,

I have been a time nut for some time now. I think I've become a Volt nut
too! I build the Silicon Chip magazine Voltage reference late last year 
but

didn't have anything to compare it against so I bought a Fluke 732A DC
reference standard.



I there a group I can subscribe to that can help me with this?



Can I coin the phrase; A man that has one DC Voltage standard knows how
accurate his meter is, whereas a man with two standards is not quite sure!



Regards,

Nic

VK2KXN VK5ZAT

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Re: [time-nuts] Non electrical time-nuttery

[Don Latham]

I'm not absolutely certain, Hal, but I think high Q has to do with the 
spectral purity of the source, but not necessarily with its long term 
stability, which depends on other design factors. I can only say about the 
damping that I dimly remember it in connection with the Shortt clocks but 
cannot remember where.
This track caused me to go into my stacks (I really thought I was free of 
the pendulum compulsion, but apparently 'taint so). There are two books i'd 
recommend:
Mathys, Robert J, "Accurate Clock Pendulums",Oxford University Press, NY, 
2004, ISBN0 19 852971 6 (Hbk) ; this is a real bible about vertical pendula. 
Amazon lists this one, both used and new
And for a personal, very entertaining, refreshing, and thorough examination 
of pendulum clock building,
Woodward, Philip, "My own Right Time : An Exploration of Clockwork Design", 
Oxford University Press, NY, 1995, ISBN 0 19 856522 4 I really enjoyed this 
book! Amazon has this one both used and new.
If you get these used, you'll spend about $170, but you will avoid endless 
hours of fooling around. OTH if the fooling around amuses, then. . .
BTW, Invar has a really low tempcoefficient, but tends to random shifts in 
its structure, yielding to abrupt length changes. Can't have everything, I 
suppose...


Best to all,
Don Latham




- Original Message - 
From: "Hal Murray" 
To: "Discussion of precise time and frequency measurement" 


Sent: Monday, January 11, 2010 8:04 PM
Subject: Re: [time-nuts] Non electrical time-nuttery




d...@montana.com said:

Also, according to some info I read on pendulum clocks, vacuum does
not work because some viscous drag is needed to damp the free
pendulum;


Why do I need damping?

I thought the general idea on oscillators was to get the highest Q (lowest
damping) that was reasonable.  But now that I think about it, I'm not sure
why.


--
These are my opinions, not necessarily my employer's.  I hate spam.




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