[time-nuts] Pendulum clock suspension

[iovane--- via time-nuts]

This puzzled me since yesterday as I discovered how the suspension of pendulum 
clocks is made, that is a springy plate.
I thought that:
-the suspension point (i.e. the point the pendulum moves about) cannot be 
considered fixed,
-following the above, the lenght of the pendulum varies during a swing,
-the spring contributes to the oscillation (it cumulates and releases energy), 
i.e. not only gravity at work..
Ok that we can neglect the above yet having an extremely good approximation, 
but is it conceptually right?
Thanks for the answers.
ant
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Re: [time-nuts] Fwd: [hpsdr] SDR experiment for the solar eclipse

[iovane--- via time-nuts]

there is no reason for an eclipse to affect time. However, working on the 1999 
data made available by the German group, I had found a periodicity in the noise 
in one of the time series. In particular, a pattern (a peak) was repeated every 
35 minutes, which was the periodicity recorded by a gravimeter in Trieste 
(Italy)
http://xoomer.virgilio.it/iovane/xtrieste.htm
I discarded those data because they didn't match in time the Trieste's 
disturbances.
I suspect that an eclipse-related cause might affect in some way the atomic 
clock circuitry (or even magnetic shielding) with a (weak)  possibility of 
causing artifacts.

Keep an open eye.

i8iov

> 
> Il 4 agosto 2017 alle 16.22 Tom Van Baak  ha scritto:
> 
> > > 
> > We were originally going to put a 5071A-locked beacon on three ham
> > bands, but decided WWV and CHU would be better sources, and 
> > logistics
> > were turning into a problem: I'm going to be doing my wideband 
> > recording
> > from a cottage in northern Michigan. But I'm still a time-nut, so 
> > the
> > receiver will be GPSDO-controlled, and there will be a stratum 1 NTP
> > server in the cottage to provide timestamps. :-)
> > 
> > John
> > 
> > > 
> Hi John,
> 
> My favorite write-up about atomic clocks and eclipses (a null result) is 
> at:
> 
> http://www2.mpq.mpg.de/~haensch/oldStuff/eclipse/eclipse.html
> 
> There you will find a good summary, thorough methodology, and many plots 
> for the 1999 eclipse. Plus they posted all the raw data (H-maser, cesium, 
> rubidium), a time-nuts dream. There is no model for why an eclipse should 
> affect time at the atomic (quantum) level so a null result is fine. If 
> nothing else, it sets an upper bound on measurement precision or a lower 
> bound on clock anomalies, if they exist.
> 
> Much more dramatic is what an eclipse might do to the ionosphere, as this 
> may affect both GPS and HF radio. So I'm very please to see the ham community 
> milking this rare opportunity for all it's worth.
> 
> /tvb
> 
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Re: [time-nuts] The clocks at Windsor Castle, UK

[iovane--- via time-nuts]

THAT was the time is the best comment


>Messaggio originale
>Da: "Will Kimber" 
>Data: 17/06/2017 4.22
>A: 
>Ogg: Re: [time-nuts] The clocks at Windsor Castle, UK
>
>And when those clocks were made there was no thought that in few
>centuries time a system that decrees that the time be put forward and
>back would be invented. They ran continuously and THAT was the time!
>
>Will
>
>On 06/17/2017 01:05 PM, William H. Fite wrote:
>> The clocks at Windsor range from C14 wooden-geared pieces to French
>> masterpieces of haute horlogerie with multiple complications including
>> perpetual calendars, sidereal time, equation of time, true local solar
>> time, date of Easter, various star charts and astronomical data, orreries,
>> animated figures and other automata. The more exotic and delicate of these
>> are not run continually but are started up periodically to test their
>> operation and when the Royals wish to demonstrate them to guests.
>>

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Re: [time-nuts] Next Aug 21 eclipse and time flow

[iovane--- via time-nuts]

As far as atomic clocks are involved, I wish to better point out where I stand, 
along with some tips and info.

- no exotic physics;   
- gravity is totally extraneous;  
- time is not involved;  
- the recorded anomalies are instrumental artifacts. The instruments responded 
to something however related to the eclipse, but not to nothing.   
- there are already known effects of solar eclipses on ionosphere, 
temperature, pressure, winds etc., but my interest doesn't go there;   
- the effects of solar eclipses on the magnetosphere are much less known, They 
might be rather local around the eclipse path. Note that the vacuum of solar 
wind is not coaxial to the optical shadow as solar wind has its own path 
following the Parker spiral (google it) whose shape is further affected by 
several variables;  
- I would recall that sudden geomagnetic variations (such as following a 
*switched off* solar wind)  might induce currents in conductors (even mu-
metal);
- along with sudden geomagnetic disturbances, also the disturbance of the 
stream of particles might be involved;  
- is is mandatory to look at EFC, as the failing component might just be the 
crystal;   
Maybe more to come.  

The above highlights that this not a time-nuts stuff, but time-nuts happen to 
own an intrument that seems to have responded sometimes in some way to the 
occurrence of a solar eclipse.   
I would stress once again that this is a unique opportunity of study.   

Antonio I8IOV


>Messaggio originale
>Da: "Magnus Danielson" 
>Data: 29/05/2017 10.43
>A: 
>Cc: 
>Ogg: Re: [time-nuts] Next Aug 21 eclipse and time flow
>
>Hi,
>
>On 05/29/2017 09:56 AM, Poul-Henning Kamp wrote:
>> 
>> In message 
>> , Michael Wouters writes:
>>
>>> The effect you're looking for depends on a comparison of two different
>>> kinds of atomic clocks eg Cs vs H-maser so the maser comparison presumably
>>> will be a null measurement.
>>
>> It would have to be between clocks where the clock-atoms have very
>> different masses (for instance Cs vs. H) but it would *also* have to
>> be clocks where the clock-photons have very different energy.
>>
>> So the best setup would be H-maser Cs or Rb foundtain and an trapped
>> ion optical clock.
>>
>> Since any physicists at NIST will be keenly aware of the Nobel
>> Prize dangling in front of any competently measured effect, I think
>> we can trust them to be on the ball :-)
>>
>
>Somewhat south of NIST Boulder is the USNO backup clock at Shriever 
>Airforce base, just next to the GPS Master Clock. USNO has rubidium 
>fountains and hydrogen masers there, and some cesiums. If there would be 
>any significant effect, I'm sure USNO would also look at it, and also 
>compare to its Washington DC set of clocks.
>
>Honestly, I'm sceptical that there is very much going on there. We have 
>three orbital masses that will almost align, but they almost align on a 
>regular basis, it's just that the shadow of the moon just don't hit the 
>earth very often. The graviational pull of moon, sun and earth keeps 
>adding continuously so we should already be able to measure these 
>individual effects separately and not only when it happens to occur at 
>the same time.
>
>What we can expect is the effect of the shadow, which can potentially 
>affect the ionspheric TEC delay and for that matter temperature of 
>troposphere and thus delay there, and that way cause our measurements to 
>get skewed. This has however nothing to do with the clocks itself.
>
>Humans is a bit too occupied by alignment in the sky. While a nice show, 
>I'm not to impressed about its scientific significance in this case. 
>There is things to learn from most perturbations sure, but as always, 
>some reasoning to sort out what we could expect is always good.
>
>Cheers,
>Magnus
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Re: [time-nuts] Next Aug 21 eclipse and time flow

[iovane--- via time-nuts]

My suspicion is just about the solar wind being switched off, which also has 
effects on the magnetosphere.  
Anyway, this very unique opportunity should not be lost.
Antonio I8IOV


>Messaggio originale
>Da: "Neville Michie" 
>Data: 29/05/2017 10.18
>A: "Discussion of precise time and frequency measurement"
>Ogg: Re: [time-nuts] Next Aug 21 eclipse and time flow
>
>
>Maybe there is an effect when the solar wind is switched off for half an 
hour.
>The ionosphere may shift in that time. This is a great opportunity when an 
impulse 
>is applied to the system. The switching off of the solar UV is sure to affect 
the 
>ozone layer. You will not have an opportunity to make these observations 
again for
>a long time. A good OCXO will keep time for half an hour, will the apparent 
GPS time
>show a deviation?
>
>cheers, 
>
>Neville Michie
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[time-nuts] Next Aug 21 eclipse and time flow

[iovane--- via time-nuts]

On august 21 2017 a solar eclipse will sweep USA from coast to coast. A 
lifetime opportunity to do coordinated experiments to check this or that. One 
of the questions that doesn't have a final answer yet is whether or not solar 
eclipses could affect the flow of time. They exist conflicting reports: 
Negative: http://www.nature.com/nature/journal/v402/n6763/full/402749a0.html 
Positive: http://home.t01.itscom.net/allais/blackprior/zhou/zhou-1.pdf  
http://home.t01.itscom.net/allais/blackprior/zhou/zhou-2.pdfPersonally I 
believe that the positive results were due to spurious responses of the atomic 
clocks to something else than gravity, or the clocks failed for some reason 
(e.g. jumping crystals then steered), or lower quality clocks had been sold to 
China. Anyway the recorded data do show an anomaly.As far as I know, no atomic 
clock tests are planned anywhere for that circumstance, but sincerely I don't 
believe this is the truth.Maybe the US time-nuts community, using its plenty 
 of atomic clocks, could give the final answer doing tests during the above 
mentioned eclipse.US time-nuts, what about the idea of doing yourselves a large 
scale coordinated test? Or do you actually believe that this question is 
already definitively closed?(Even discovering that atomic clocks might respond 
to someting else than gravity would be of great interest).Antonio I8IOV
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Re: [time-nuts] Car Clock drift - the lowly 32kHz tuning fork crystal specs

[iovane--- via time-nuts]

>I only set the car clock twice a year, at daylight savings time changes.
>Yet between daylight savings time changes, the car clock never drifts by
>more than a minute.

Just to testify that I do exactly the same on the clock of my old mercedes. I' 
ve alwais been unable to estimate the half-year drift because it is always very 
less than 1 minute.

iov
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Re: [time-nuts] Antique precision timing device without electronics

[iovane--- via time-nuts]

This is mine, used to calibrate some aircraft related equipment:

https://www.flickr.com/photos/103726899@N08/33326340242/in/dateposted-public/ 

and its diagram:

https://www.flickr.com/photos/103726899@N08/33482556075/in/dateposted-public/

iov


>Messaggio originale
>Da: "Mike Seguin" 
>Data: 16/03/2017 22.33
>A: "Discussion of precise time and frequency measurement"
>Ogg: Re: [time-nuts] Antique precision timing device without electronics
>
>Very interesting use of a tuning fork.
>
>I have only seen this once before. I have the tuning fork used with an 
>Ampex Model 300 reel to reel tape machine. The tuning fork was used as a 
>reference in the power supply that drove the capstan motor for accurate 
>speed.
>
>It's 60 Hz not 25 Hz. It's marked B E Eisenhour. Patent is here:
>
>https://www.google.com/patents/US1880923
>
>Pic is here:
>
>https://www.dropbox.com/s/opmxr521qqkx76r/60%20Hz%20Fork.jpg?dl=0
>
>Mike
>
>On 3/16/2017 2:04 PM, Bill Hawkins wrote:
>> Hi Morris,
>>
>> If there's no active devices (and you'd be sure to see them, not solid
>> state) where does the power to operate the motor come from? Is it the
>> same contacts that drive the fork?
>>
>> It's amazing that there is high Q when contacts must be operated by the
>> fork.
>>
>> Did it come with instructions for setting the weights at the end of the
>> fork tines?
>>
>> Best regards,
>> Bill Hawkins
>>
>> -Original Message-
>> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Morris
>> Odell
>> Sent: Thursday, March 16, 2017 4:23 AM
>> To: time-nuts@febo.com
>> Subject: [time-nuts] Antique precision timing device without electronics
>>
>> Hi all,
>>
>> I was recently asked to resurrect this interesting device by a colleague
>> who collects antique scientific instruments. It's a "Chronoscope" made
>> by the H. Tinsley company in London in the early 20th century and used
>> to measure time intervals with the precision of those days. It's large
>> and heavy in a polished wooden case with a top deck that hinges up to
>> reveal the innards.
>>
>> The timing reference is a large tuning fork about 30 cm (1 foot) long
>> and running at 25 cps. It's normally in a glass fronted housing (removed
>> for the video) that includes a pair of hinged mechanical arms for
>> starting it. It's maintained in oscillation by an electromagnet and
>> contact arrangement powered from a 12V DC supply. The fork amplitude is
>> controlled by a rheostat - too much and the tines impact on the magnet.
>> The video frame rate makes the fork look slower than it actually is. I
>> was able to extract a signal and measure the frequency with a modern GPS
>> disciplined counter - it's 0.007% off its specified 25 Hz! The frequency
>> is too low for my HP 5372A so I was not able to easily get an idea of
>> stability or do an ADEV measurement. The fork has quite a high Q and
>> takes over a minute to stop oscillating after the power is turned off.
>> There's a built in higher voltage AC power supply, probably a mains
>> transformer, potted in beeswax in a polished wooden box inside that is
>> intended to
>>   energise a large neon strobe lamp used to adjust the fork.
>> Unfortunately the lamp was not with the unit and is no doubt
>> irreplaceable.
>>
>> The 25 Hz signal is filtered by an LC network  and used to run a
>> synchronous motor in the Chronoscope unit. Synchronous motors not being
>> self-starting, you need to tweak a knob to get it going - there's a joke
>> in there but I can't for the life of me think what it could be ?? The
>> "Contact" switch and associated socket on the back controls an
>> electromagnetic clutch that connects the clockwork counter mechanism to
>> the motor and the contact "on" time is indicated on the dials with 10 mS
>> resolution.
>>
>> There's not a single active device in there and after a clean and lube
>> it runs very nicely from a modern 12V DC plugpack. My friend is very
>> pleased with it and it will take pride of place in his collection.
>>
>> I'd be interested to know if any time nuts have knowledge or experience
>> of this lovely instrument.
>>
>> A video of it is at  https://youtu.be/i5S8WS9iN_E
>>
>> Enjoy!
>>
>> Morris
>>
>>

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Re: [time-nuts] Vintage Frequency Measurement

[iovane--- via time-nuts]

This Canadian RCA apparatus was also called wavemeter but is a heterodyne 
frequency meter and a signal generator.

https://www.pa3esy.nl/military/us/meet/TE149/html/te149_set-gb.html 

iov


>Messaggio originale
>Da: "Tim Shoppa" 
>Data: 15/02/2017 17.29
>A: "Discussion of precise time and frequency measurement"
>Ogg: Re: [time-nuts] Vintage Frequency Measurement
>
>For those of us who have to translate between the old "cps" and the modern
>"Hz", I found this handy conversion table on the web:
>http://www.aqua-calc.com/convert/frequency/hertz-to-cycle-per-second
>
>Tim N3QE
>
>[image: Inline image 1]
>
>On Tue, Feb 14, 2017 at 5:29 AM, Peter Vince 
>wrote:
>
>> On 14 February 2017 at 04:23, Raj  wrote:
>>
>> > I have a Marconi T.F. 643 C, in Megacycles !
>> >
>>
>> Ah, a sensible, descriptive name for the unit.  Some of these modern units
>> really do Hert(z) :-)
>>
>>  Peter
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Re: [time-nuts] FS HP 5335A

[iovane--- via time-nuts]

The HP 5335A born with factory installed option 010 might happen not to have 
both the regular crystal and the jumper at all. This is the case of one of 
mine.

Antonio I8IOV

>Messaggio originale
>Da: Tom Holmes 
>Data: 18/05/2016 4.06
>A: "Discussion of precise time and frequency measurement"
>Ogg: Re: [time-nuts] FS HP 5335A
>
>HI Bob...
>
>Thanks for the tip. Have been down that road with this one and it didn't fix 
it. I think someone may have deliberately disabled the internal timebase to 
prevent users from having anything but the house standard in play. 
>
>Tom Holmes, N8ZM
>
>-Original Message-
>From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Stewart
>Sent: Tuesday, May 17, 2016 7:08 PM
>To: Discussion of precise time and frequency measurement 
>Subject: Re: [time-nuts] FS HP 5335A
>
>Hi,
>
>I know this is a for sale post, but there's a jumper that needs to be there 
to work with the regulator oscillator.  Page 2-4 of the Operating and Service 
Manual (05335-90021) details the instructions for installing the Option 010, 
the 10811 OCXO.  Instruction "c" is below.  You'd need to add the jumper back 
in.  The factory jumper looks like a resistor.  It may simply be cut with side 
cutters on your unit.  You can use just a piece of wire, of course.
>
>"c. Remove electrical lead (jumper), PIN 8159-0005, that connects A4U1B(6) 
and U2B(6)."
>
>Bob

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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[iovane--- via time-nuts]

Wayne,

I suggest another test too, but this requires a bit of luck.
Power up the unit, and wait until it warms up, say 5 minutes. The VCXO voltage 
will stuck at 14.5V. Then power down the unit in order to restart the sweep 
cycle, just enough, say one second, then power up. If you are lucky and the 
VCXO voltage at lock would be greater than your 7.2V, you will get a lock. As 
your BITE signal is always low, you could notice the lock just looking at pin 
9, which will not reach 14.5V. This worked for me, but will not work if the 
VCXO voltage at lock would be less than your 7.2V.

Antonio I8IOV

>Hi
>
>Which strongly suggests that the BITE line is telling the truth. The unit is 
not in lock
>and it’s broke. If you have the gear, you can verify this by running the tune 
input up and
>down and seeing if the output varies by about 0.02 Hz or not. 
>
>Bob
>
>> On Mar 22, 2016, at 11:36 PM, Wayne Holder  wrote:
>> 
>> The signal on pin 9 starts at about 7.2 volts then slowly increments up to
>> 14.5 volts over a period of about 138 seconds.  It then seems to stay stuck
>> at 14.5 volts and only repeats the cycle if I power down,w wait and then
>> power back on.
>> 
>> Wayne

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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[iovane--- via time-nuts]

Hey Wayne,
I said "you should read more than 1 Mohm", but if R215 is interrupted, of 
course.
Antonio





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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[iovane--- via time-nuts]

>From: Hal Murray 
>
>iovane wrote:
>> are you sure your LPRO actually locks? You say you have measured 10.000 MHz
>> but you don't mention the other decimals. Some years ago I characterized
>> some  LPROs of mine, and from my notebook I take that, on one sample for
>> instance,  prior to lock the frequency swept up and down between (about)
>> 9.999860 and  10.000230.

>How long does it take to do a sweep cycle?
>
>If your gear is averaging over a longer time to get a more accurate 
frequency 
>value, will it give you the average frequency?

A sweep cycle lasts in the order of the minute. Typically the LPRO locks in 
about 3.5 minutes. I used gate time of 0.1 and 1 second on a 9 digit counter.

Antonio I8IOV

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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[iovane--- via time-nuts]

Perfect !!
The swept voltage should not reach 14V, but only about 12.5V and then reverse. 
Your upper comparator is faulty. Check resistor R215 on the PCB bottom face, 
100K SMD. You could chech it on board, and probably you will read more than 1 
Mohm. I bet the trouble is there. R215 is near the longer slot and is of the 
smallest size.
Antonio I8IOV



From: Wayne Holder <wayne.hol...@gmail.com>


I don't currently have a way to accurately measure the frequency of the output, 
but my assumption is that oscillator is running, but not locked.  I did some 
more poking around and found that the crystal volts monitor (pin 9) starts low 
(around 4 volts) and then slowly rises as the unit runs.  It rises to about 14 
volts and then stops.  So, this may be a similar problem to what you described. 
 However, lacking proper schematics, I'm not sure where to look next.
Wayne
On Tue, Mar 22, 2016 at 8:43 AM, iovane--- via time-nuts <time-nuts@febo.com> 
wrote:
Wayne,



are you sure your LPRO actually locks? You say you have measured 10.000 MHz

but you don't mention the other decimals. Some years ago I characterized some

LPROs of mine, and from my notebook I take that, on one sample for instance,

prior to lock the frequency swept up and down between (about) 9.999860 and

10.000230. Such a span was rather typical among units. A faulty unit of mine

remained stuck at the upper limit without reversing the sweep. This was due to

a faulty resistor in one of the two (upper) voltage comparator circuits. Anyway

I don't know if this would affect the BITE, but I suggest you to check the

other decimals.



Antonio I8IOV



>

>The BITE signal is the only way to to know if it has a lock...

>

>Wayne

>

>> On Mar 22, 2016, at 4:37 AM, Bob Camp <kb...@n1k.org> wrote:

>>

>> Hi

>>

>> There are probably a dozen or more things that contribute to the BITE

output. It could be

>> a regulator out of range. It also could be the VCXO nearing tune limit. If

the unit locks up and

>> seems to work, I’d ignore it and move on.

>>

>> Bob

>>

>>> On Mar 21, 2016, at 9:42 PM, Wayne Holder <wayne.hol...@gmail.com> wrote:

>>>

>>> I have a surplus LPRO-101 that seems to power up OK.  The power draw

starts

>>> at 1.7 Amps and then, after a few minutes, drops down to 600 mA, or so

and,

>>> after this startup, the output shows a 10.000 MHz signal thats 's

>>> accurately as I can measure it.  The lamp voltage is 6.2 volts, which

seems

>>> within spec.  However, the BITE signal that's supposed to indicate lock

>>> with a LOW level is always LOW and never changes.  The docs say that BITE

>>> signal should start at a HIGH level to indicate no lock and then drop to a

>>> LOW when lock is obtained.  So, this behavior seems all wrong.

>>>

>>> I opened the case and observed the purple glow of the lamp and probed

>>> around IC U401, which buffers the BITE signal, and saw the same signal LOW

>>> level.  U401 is getting 5 volt power and the inputs to the AND gate used

as

>>> a buffer for the BITE signal match what I'd expect.  But, lacking a proper

>>> schematic, I'm not sure how to trace this back to the problem.  Has anyone

>>> ever seen a symptom like this with an LPRO101?

>>>

>>> Wayne

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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[iovane--- via time-nuts]

Wayne,

are you sure your LPRO actually locks? You say you have measured 10.000 MHz 
but you don't mention the other decimals. Some years ago I characterized some 
LPROs of mine, and from my notebook I take that, on one sample for instance, 
prior to lock the frequency swept up and down between (about) 9.999860 and 
10.000230. Such a span was rather typical among units. A faulty unit of mine 
remained stuck at the upper limit without reversing the sweep. This was due to 
a faulty resistor in one of the two (upper) voltage comparator circuits. Anyway 
I don't know if this would affect the BITE, but I suggest you to check the 
other decimals.

Antonio I8IOV 

>
>The BITE signal is the only way to to know if it has a lock...
>
>Wayne
>
>> On Mar 22, 2016, at 4:37 AM, Bob Camp  wrote:
>> 
>> Hi
>> 
>> There are probably a dozen or more things that contribute to the BITE 
output. It could be
>> a regulator out of range. It also could be the VCXO nearing tune limit. If 
the unit locks up and
>> seems to work, I’d ignore it and move on.
>> 
>> Bob
>> 
>>> On Mar 21, 2016, at 9:42 PM, Wayne Holder  wrote:
>>> 
>>> I have a surplus LPRO-101 that seems to power up OK.  The power draw 
starts
>>> at 1.7 Amps and then, after a few minutes, drops down to 600 mA, or so 
and,
>>> after this startup, the output shows a 10.000 MHz signal thats 's
>>> accurately as I can measure it.  The lamp voltage is 6.2 volts, which 
seems
>>> within spec.  However, the BITE signal that's supposed to indicate lock
>>> with a LOW level is always LOW and never changes.  The docs say that BITE
>>> signal should start at a HIGH level to indicate no lock and then drop to a
>>> LOW when lock is obtained.  So, this behavior seems all wrong.
>>> 
>>> I opened the case and observed the purple glow of the lamp and probed
>>> around IC U401, which buffers the BITE signal, and saw the same signal LOW
>>> level.  U401 is getting 5 volt power and the inputs to the AND gate used 
as
>>> a buffer for the BITE signal match what I'd expect.  But, lacking a proper
>>> schematic, I'm not sure how to trace this back to the problem.  Has anyone
>>> ever seen a symptom like this with an LPRO101?
>>> 
>>> Wayne
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Re: [time-nuts] LPRO-101 BITE (~lock) Signal Always Low

[iovane--- via time-nuts]

>Da: Tom Miller 
>
>- Original Message - 
>From: "Wayne Holder" 
>
>
>>I have a surplus LPRO-101 that seems to power up OK.  The power draw starts
>> at 1.7 Amps and then, after a few minutes, drops down to 600 mA, or so 
>>...
>> schematic, I'm not sure how to trace this back to the problem.  Has anyone
>> ever seen a symptom like this with an LPRO101?
>>
>> Wayne
>
>Does it need a pull up resistor?

No pull-up resistor required, it should work.

Antonio I8IOV
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[time-nuts] Counter?

[iovane--- via time-nuts]

This tube type item on ebay is equipped with E1T high speed decade counting 
tubes.
222022951573

I'm not affiliated,  etc...
Antonio i8iov

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Re: [time-nuts] Seeking HP 3561A schematic diagrams

[iovane--- via time-nuts]

Volume 2 actually contains Section VII (250 pages) with schematics. I bought a 
reasonably good scan, including oversized fold outs, at Qservice in Greece for 
25 dollars (ebay item 380066695055 ). For fairness to the seller,I donì't offer 
to send you a copy. If I remember, it is possible to save on shipping asking 
the seller to send a copy by email.
Antonio I8IOV

>Messaggio originale
>Da: Dan Rae 
>Data: 12/02/2016 21.33
>A: "Discussion of precise time and frequency measurement"
>Ogg: Re: [time-nuts] Seeking HP 3561A schematic diagrams
>
>On 2/12/2016 11:28 AM, Charles Steinmetz wrote:
>> I'm helping a colleague resurrect a hard-luck HP 3048A phase noise 
>> measurement system.  In particular, he asked me to help get the 3561A 
>> dynamic signal analyzer working again.  I downloaded Volume 1 of the 
>> service manual from Keysight, which contains Sections I through VI but 
>> does not contain Section VII (schematics and service information).  I 
>> suspect that Section VII is Volume 2 of the manual, but do not know 
>> for sure.
>>
>>
>Vol 2 does indeed contain all the schematics and is about 2 inches thick 
>with a lot of oversized fold outs, it will not be an easy one to 
>scan...  There is also an operating manual.  Have you asked Dave at 
>Artek, he might have one in the pending pile?
>> (I'm not sure if there are any hardware differences between "regular" 
>> 3561As and the ones supplied as part of the 3048A system.  I'm pretty 
>> sure the faults [at least the major ones] lie in the basic hardware, 
>> so I don't think we need schematics particular to the 3048A if there 
>> are differences.)
>>
>The 3048 system uses a standard (working!) 3561A.  There are no 
>differences.  I don't think the optional extra memory is required either.
>
>Dan

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Re: [time-nuts] Glass Envelope Quartz Crystals

[iovane--- via time-nuts]

I think that these crystals were designed to be placed in an oven, which worked 
as a shield too. I have a similar crystal made by Racal in the 60's, and in my 
case it is fitted with the classic octal tube-type plug. It was housed (still 
is) in a heavy massive shimmering chrome-plated cylindrical brass enclosure, a 
beauty to see, It was the timebase of a tube-type synthesizer with lots of 
tubes. Themperature control was achieved by means of a mercury thermometer in 
which mercury actuated a contact when reaching a wire crossing the capillary 
tube.

Antonio I8IOV

>Da: Bob Camp 
>Data: 02/02/2016 13.15
>A: "Discussion of precise time and frequency measurement"
>Ogg: Re: [time-nuts] Glass Envelope Quartz Crystals
>
>Hi
>
>Since the 25 MHz crystal has already been soldered into a circuit, putting it 
in a 
>socket is probably not a real good idea. It’s also a leaded part. Even with 
fat pins
>sockets can be an issue. With wire leads, you are asking for trouble. 
>
>Functionally, there is little there is little difference between a glass 
package crystal 
>and a metal package. About the only real one is the obvious - one has a metal 
shield
>you can (but sometimes don’t)  ground. 
>
>Bob
>
>
>> On Feb 1, 2016, at 9:58 PM, Daniel Watson  wrote:
>> 
>> Hi,
>> 
>> I purchased a pair of interesting glass envelope crystals for a project.
>> Here are some pictures:
>> 
>> http://syncchannel.blogspot.com/2016/02/glass-envelope-quartz-crystals.html
>> 
>> Does anyone have an idea about what mount/socket I should buy for these? I
>> read a previous thread on the list about Bliley crystals using a B7G mount,
>> but I'm not sure if that type might work here.
>> 
>> Also, when building up a circuit to make these oscillate, are there any
>> specific differences about crystals in this package that I should keep in
>> mind?
>> 
>> 
>> Thanks much,
>> 
>> Dan W.


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[time-nuts] Why sunspots affect a pendulum?

[iovane--- via time-nuts]

In the other thread "How did they distribute time in the old days?" Bill wrote:
> It loses or gains about a minute a month
>depending on the moon phase or sunspots. 

Why should sunspots affect the rate of a pendulum clock? Sunspots are not 
related to gravity. What about?  Any other kind of clocks is affected by 
sunspots? Who knows? Is what Bill stated reliable? Any paper or website about?I 
would be interested in recorded pendulum clock drift data.
Antonio I8IOV
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Re: [time-nuts] Why sunspots affect a pendulum?

[iovane--- via time-nuts]

>Antonio - that sunspot comment was made as a joke!
>
>73,
>
>Bill

Ok, I really didn't realize this.
73,
Antonio

>
>-Original Message-
>From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of iovane---
>via time-nuts
>Sent: Wednesday, October 14, 2015 12:31 PM
>To: time-nuts@febo.com
>Subject: [time-nuts] Why sunspots affect a pendulum?
>
>In the other thread "How did they distribute time in the old days?" Bill
>wrote:
>> It loses or gains about a minute a month depending on the moon phase 
>>or sunspots.
>
>Why should sunspots affect the rate of a pendulum clock? Sunspots are not
>related to gravity. What about?  Any other kind of clocks is affected by
>sunspots? Who knows? Is what Bill stated reliable? Any paper or website
>about?I would be interested in recorded pendulum clock drift data.
>Antonio I8IOV

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Re: [time-nuts] HP 3586A documents

[iovane--- via time-nuts]

I attach the schematics. I could send you off list my copy of the PRACTICAL 
GUIDE these schematics are taken from. Let me know.
Antonio I8IOV


Messaggio originale
Da: kc0...@gmail.com
Data: 21/06/2015 20.38
A: Discussion of precise time and frequency measurementtime-nuts@febo.com
Ogg: [time-nuts] HP 3586A documents

I have recently acquired a used HP 3586A.

Awhile back, in 2013, there was a thread that discussed the availability 
of Mr. Bill Feldman's A PRACTICAL GUIDE FOR USING THE HP3586A.pdf, 
which I have found on the BAMA website. However, as pointed out in the 
earlier thread, the schematics for the various accessories are not 
contained in the document.

Has anyone since found the relevant PDF files (I believe that they are 
named C1-C2.PDF, C3.PDF).

There was also, apparently, a list of caps that should be replaced in 
this instrument. If anyone has a copy of that, it would be very useful 
to me.

Thanks
DaveD
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[time-nuts] GPS data show how Nepal quake disturbed ionosphere

[iovane--- via time-nuts]

http://www.nasa.gov/jpl/gps-data-show-how-nepal-quake-disturbed-earth-s-upper-atmosphere
 

starting from there I've found also this interesting link 
http://igs.org/network 

I was not aware of.
Antonio I8IOV
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