Re: [time-nuts] Very Accurate Delta Time RF Pulse Measurements

[Scott Stobbe]

Taking a look for it also turned up a recent time-nuts thread

https://www.febo.com/pipermail/time-nuts/2016-May/097801.html

On Thursday, 28 July 2016, Scott Stobbe  wrote:

> There was a pic app note on alternate uses for the cap sense block a while
> back, not sure it that it will push you into the ps.
>
> On Thursday, 28 July 2016, Jerome Blaha  > wrote:
>
>> Hi Guys,
>>
>> This is a little outside of time-nuts scope, but not by much.  I'm
>> interested in finding the time between two rising edges above a set
>> threshold with preferably nS or high ps timing accuracy.  Can this be
>> simply done with a few programmed Microchip PICs or with a good short term
>> OCXO clock?  The issue I see is that a 10Mhz timing reference with 1 cycle
>> difference in time yields 100ns resolution, which is far too large, so
>> maybe a PIC can solve this.
>>
>> This weekend project would be a multi-element antenna array, each with a
>> super-fast response log peak power detector fed into several PICs for time
>> of arrival.  Whenever a nearby high energy RF pulse is detected, the time
>> of arrival between two antenna elements and hence the direction toward the
>> TX could be roughly computed.  Some typical log peak detectors have an 8ns
>> input pulse response time, so I'm hoping that rise times are similar
>> between multiple detectors, negating the delayed response.
>>
>> There are time of arrival/AoA systems out there with synthetic doppler,
>> phased arrays, correlative interferometers, and phase comparators, but it
>> would be interesting to accomplish super wideband AoA timing on two rising
>> pulses with relatively cheap parts.
>>
>> Thanks,
>>
>> -Jerome
>> ___
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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] Very Accurate Delta Time RF Pulse Measurements

[Bob Camp]

Hi

If you have a need to do < 1 ns with a counter approach, the counter will need 
to have a GHz clock in it. If you want to use an MCU counter, it will need to 
have a GHz level clock routed to it. You are unlikely to find an MCU that will 
do that. An FPGA can get you to 1.25 ns with direct counting. With gate based 
delay line techniques you can get down below 100 ps in an FPGA. 

The other approach is to build a counter to get as fast as you practically can 
and then do an analog TDC to get a few more bits. 

There are a *lot* of messy details past all that.

Bob

> On Jul 28, 2016, at 7:12 PM, Jerome Blaha  wrote:
> 
> Hi Guys,
> 
> This is a little outside of time-nuts scope, but not by much.  I'm interested 
> in finding the time between two rising edges above a set threshold with 
> preferably nS or high ps timing accuracy.  Can this be simply done with a few 
> programmed Microchip PICs or with a good short term OCXO clock?  The issue I 
> see is that a 10Mhz timing reference with 1 cycle difference in time yields 
> 100ns resolution, which is far too large, so maybe a PIC can solve this.
> 
> This weekend project would be a multi-element antenna array, each with a 
> super-fast response log peak power detector fed into several PICs for time of 
> arrival.  Whenever a nearby high energy RF pulse is detected, the time of 
> arrival between two antenna elements and hence the direction toward the TX 
> could be roughly computed.  Some typical log peak detectors have an 8ns input 
> pulse response time, so I'm hoping that rise times are similar between 
> multiple detectors, negating the delayed response.
> 
> There are time of arrival/AoA systems out there with synthetic doppler, 
> phased arrays, correlative interferometers, and phase comparators, but it 
> would be interesting to accomplish super wideband AoA timing on two rising 
> pulses with relatively cheap parts. 
> 
> Thanks,
> 
> -Jerome
> ___
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Re: [time-nuts] Very Accurate Delta Time RF Pulse Measurements

[Scott Stobbe]

There was a pic app note on alternate uses for the cap sense block a while
back, not sure it that it will push you into the ps.

On Thursday, 28 July 2016, Jerome Blaha  wrote:

> Hi Guys,
>
> This is a little outside of time-nuts scope, but not by much.  I'm
> interested in finding the time between two rising edges above a set
> threshold with preferably nS or high ps timing accuracy.  Can this be
> simply done with a few programmed Microchip PICs or with a good short term
> OCXO clock?  The issue I see is that a 10Mhz timing reference with 1 cycle
> difference in time yields 100ns resolution, which is far too large, so
> maybe a PIC can solve this.
>
> This weekend project would be a multi-element antenna array, each with a
> super-fast response log peak power detector fed into several PICs for time
> of arrival.  Whenever a nearby high energy RF pulse is detected, the time
> of arrival between two antenna elements and hence the direction toward the
> TX could be roughly computed.  Some typical log peak detectors have an 8ns
> input pulse response time, so I'm hoping that rise times are similar
> between multiple detectors, negating the delayed response.
>
> There are time of arrival/AoA systems out there with synthetic doppler,
> phased arrays, correlative interferometers, and phase comparators, but it
> would be interesting to accomplish super wideband AoA timing on two rising
> pulses with relatively cheap parts.
>
> Thanks,
>
> -Jerome
> ___
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>
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Re: [time-nuts] NCOCXO anyone?

[Bruce Griffiths]

Diophantine Frequency Synthesizer Design for Timekeeping Systems
|   |
|   |  |   |   |   |   |   |
| Diophantine Frequency Synthesizer Design for Timekeepi...Abstract Diophantine 
Frequency Synthesis (DFS), a number-theoretic approach to the design of very 
high resolution frequency synthesizers, was introduced in 2006.  |
|  |
| View on www.hindawi.com | Preview by Yahoo |
|  |
|   |




Discusses a diophantine synthesiser.Note Sotiriadis' work on diophantine 
numbers and frequency synthesis appears to be a rehash of an old Patent perhaps 
due to a lack of competent searching for prior art.This issue was discussed on 
the list some time ago,
Bruce
 

On Friday, 29 July 2016 6:31 AM, Attila Kinali  wrote:
 

 On Fri, 22 Jul 2016 08:19:43 + (UTC)
Bruce Griffiths  wrote:

> No, the first one merely uses a pair of cascaded heterodyne PLLs
> as shown on p3 of the manual.

Ok. I tried to understand how this circuit works. While I can see
how a small and precise frequency offset can be produced, I do not
see how a small phase offset with fixed frequency can be produced.
At least not at the 100fs resolution level they are claiming in
the manual. Would someone be so kind and explain the working
of the circuit?

> A diophantine setup may be useful here if one wished to construct something 
> similar.

What is a diophantine setup?


                Attila Kinali

-- 
It is upon moral qualities that a society is ultimately founded. All 
the prosperity and technological sophistication in the world is of no 
use without that foundation.
                -- Miss Matheson, The Diamond Age, Neil Stephenson
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[time-nuts] phase noise in digital divider, 2nd harmonic

[life speed via time-nuts]

Hi,

Been a while since I visited, I recall there are many, well, time nuts here.  I 
am trying to track down a source of phase noise in a frequency synthesizer 
design.  One part of the frequency reference upconverts a DDS and then divides 
it down again using a digital divider - standard technique for DDS angle 
modulation spurious reduction.

The DDS tunes over more than an octave, so obviously the single low pass filter 
isn't going to cut it.  I am noticing up to 3 dB phase noise degradation at the 
output of the divider as the DDS frequency decreases and the 2nd harmonic is 
in-band to the LPF.  I suspect this is disturbing the threshold crossing in the 
high speed digital logic divider, as described in "The Effect of Harmonic 
Distortion on Phase errors in Frequency Distribution and Synthesis" by F.L. 
Walls et al at NIST.

What do you think?  I should probably put in a switched filter to get my 3 dB 
back  ;)

- Lifespeed
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[time-nuts] Very Accurate Delta Time RF Pulse Measurements

[Jerome Blaha]

Hi Guys,

This is a little outside of time-nuts scope, but not by much.  I'm interested 
in finding the time between two rising edges above a set threshold with 
preferably nS or high ps timing accuracy.  Can this be simply done with a few 
programmed Microchip PICs or with a good short term OCXO clock?  The issue I 
see is that a 10Mhz timing reference with 1 cycle difference in time yields 
100ns resolution, which is far too large, so maybe a PIC can solve this.

This weekend project would be a multi-element antenna array, each with a 
super-fast response log peak power detector fed into several PICs for time of 
arrival.  Whenever a nearby high energy RF pulse is detected, the time of 
arrival between two antenna elements and hence the direction toward the TX 
could be roughly computed.  Some typical log peak detectors have an 8ns input 
pulse response time, so I'm hoping that rise times are similar between multiple 
detectors, negating the delayed response.

There are time of arrival/AoA systems out there with synthetic doppler, phased 
arrays, correlative interferometers, and phase comparators, but it would be 
interesting to accomplish super wideband AoA timing on two rising pulses with 
relatively cheap parts. 

Thanks,

-Jerome
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Re: [time-nuts] Q/noise of Earth as an oscillator

[Jim Palfreyman]

Hi All,

Tom gave me a nudge to look here - I hadn't been following this thread.

For those that don't know, I study pulsars and so the way we measure what
pulsars do could be relevant to this discussion.

First, I have never heard of a Q measure when referencing a pulsar. I think
the key here is that it's not resonating as such. Rotating yes, resonating
no.

Pulsars spin and slow down due to giving off energy (magnetic dipole
radiation). So in the pulsar world we mainly refer to spin frequency (F0)
and frequency derivative (F1). With some of the younger and more "erratic"
pulsars, F2 (and further) can be modelled.

Here's some data on the Vela pulsar (hot off the presses - measured just
now):

F0  11.1867488542579
F1  -1.55859177352837e-11
F2  1.23776878287221e-21

Vela is young and erratic. Millisecond pulsars are outstanding clocks.
Here's the data for J0437-4715 - one of the most stable pulsars we know
about:

F0  173.6879458121843
F1  -1.728361E-15

I'm sure the "Q" of Vela would be pretty decent - but I can tell you now,
as a time-keeper, she's useless.


Jim Palfreyman



On 28 July 2016 at 20:50, Tony Finch  wrote:

> Neville Michie  wrote:
>
> > The conical pendulum has a simple form of a weight on a string, instead
> > of oscillating in one plane as a conventional pendulum, it swings around
> > in a circular orbit in the horizontal plane. It has a definite resonant
> > frequency.
>
> I don't think it does have a resonant frequency, any more than the Earth
> does: the angular velocity of the pendulum is sqrt(g/h) where h is the
> height of the pendulum; give it more energy, it swings higher, so h is
> smaller, so the frequency is higher.
>
> Tony.
> --
> f.anthony.n.finch    http://dotat.at/  -  I xn--zr8h
> punycode
> South Thames, Dover: Southwesterly 5 or 6. Slight or moderate. Rain or
> showers. Good, occasionally poor.
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Re: [time-nuts] NCOCXO anyone?

[Attila Kinali]

On Thu, 28 Jul 2016 14:06:09 -0700
Alex Pummer  wrote:

> On 7/28/2016 11:03 AM, Attila Kinali wrote:
> > On Fri, 22 Jul 2016 08:19:43 + (UTC)
> > Bruce Griffiths  wrote:
> >
> >> No, the first one merely uses a pair of cascaded heterodyne PLLs
> >> as shown on p3 of the manual.
> > Ok. I tried to understand how this circuit works. While I can see
> > how a small and precise frequency offset can be produced, I do not
> > see how a small phase offset with fixed frequency can be produced.
> > At least not at the 100fs resolution level they are claiming in
> > the manual. Would someone be so kind and explain the working
> > of the circuit?

> if you send the circuit to me Attila, I would try to help you

Ah.. sorry. the link got cut off when i trimmed the mail.
It's the one on page three in the FemtoStepper manual:
http://www.spectratime.com/products/itest/clock-instruments/FemtoStepper/


Attila Kinali

-- 
Malek's Law:
Any simple idea will be worded in the most complicated way.
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Re: [time-nuts] NCOCXO anyone?

[Alex Pummer]

if you send the circuit to me Attila, I would try to help you

73
KJ6UHN
Alex
by the way aside of that ham license, I have some fifty years of 
experience and also an MSEE


On 7/28/2016 11:03 AM, Attila Kinali wrote:

On Fri, 22 Jul 2016 08:19:43 + (UTC)
Bruce Griffiths  wrote:


No, the first one merely uses a pair of cascaded heterodyne PLLs
as shown on p3 of the manual.

Ok. I tried to understand how this circuit works. While I can see
how a small and precise frequency offset can be produced, I do not
see how a small phase offset with fixed frequency can be produced.
At least not at the 100fs resolution level they are claiming in
the manual. Would someone be so kind and explain the working
of the circuit?


A diophantine setup may be useful here if one wished to construct something 
similar.

What is a diophantine setup?


Attila Kinali



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[time-nuts] Histogram of T2 arrival times

[Hal Murray]

http://users.megapathdsl.net/~hmurray/time-nuts/T2-hist.png

24K samples from KS-24361
200K samples from Z3801A

The systems collecting the data have 200-300 microsec peak-peak of clock 
offset, mostly tracking daily temperature swings.

A major fraction of the timing difference is explained by the baud rate 
difference.  If I did the math right, there is a 12 ms difference in 
transmissions times.

-- 
These are my opinions.  I hate spam.



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Re: [time-nuts] NCOCXO anyone?

[Attila Kinali]

On Fri, 22 Jul 2016 08:19:43 + (UTC)
Bruce Griffiths  wrote:

> No, the first one merely uses a pair of cascaded heterodyne PLLs
> as shown on p3 of the manual.

Ok. I tried to understand how this circuit works. While I can see
how a small and precise frequency offset can be produced, I do not
see how a small phase offset with fixed frequency can be produced.
At least not at the 100fs resolution level they are claiming in
the manual. Would someone be so kind and explain the working
of the circuit?

> A diophantine setup may be useful here if one wished to construct something 
> similar.

What is a diophantine setup?


Attila Kinali

-- 
It is upon moral qualities that a society is ultimately founded. All 
the prosperity and technological sophistication in the world is of no 
use without that foundation.
 -- Miss Matheson, The Diamond Age, Neil Stephenson
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[time-nuts] GPS receiver time message offsets to 1PPS (updated)

[Mark Sims]

The Skylab is effectively useless for sub-second timing.  The message arrival 
time periodically jumps around,  up to +/- 300 msecs.  There are a couple of 
values that it seems to prefer, but any value can be seen.



NMEA works a lot better on most receivers that I expected.   They send several 
messages a second (and depending upon the receiver the time can appear in more 
than one message... Heather has a hierarchy of preferences for which message to 
get the time from if it sees it in more than one message.   By sending all 
those (rather long) messages each second, one might expect quite a bit of 
variation in time message arrival, but this does not appear to be the case 
(except for the Skylab).  It is also interesting that most NMEA receivers have 
their time message come out around 300 msecs +/- 100 msecs.  For a generic NMEA 
receiver, Heather uses a default correction value of -300 msecs.



---


> There is the Skylab SKM53 at 37.8 ms. I've never seen one of those, so no 
> guess about that one.

The surprise in the crowd is the Res-T SMT at 63.7 ms. I wonder what they messed
up
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[time-nuts] GPS receiver time message offsets to 1PPS (updated)

[Mark Sims]

Lady Heather keeps the date/time time in two sets of variables. One is the 
receiver time message values in UTC (or GPS) time.  The other is local time 
(UTC/GPS adjusted for time zone or time scale) that is used for the clock 
displays.  There are integer year,month,day, hours,minutes,seconds values and a 
double precision fractional seconds value.   All time calculations are done 
using these variables converted to Julian date/times.



The Motorola format time message has the hours,minutes,seconds fields and a 
separate nanosecond correction field (which can be positive or negative), which 
I convert to double by dividing by 1.0E9.  Turns out I had moved some code 
around and accidentally wound up dividing it by 1.0E9 again a few lines down, 
effectively wiping out the nanosecond correction.



The Z38xx time string has no fractional seconds value and I was not setting it 
to 0.0 when I decoded the #T2 format time string.  Originally I only supported 
the #T2 format, but when I added support for the #T1 format,  I moved the line 
that cleared the fractional seconds value to the #T1 code instead of copying 
the line.



Ahhh, the subtle joys of copy-paste code editing...



---


> And the problem was?
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Re: [time-nuts] Q/noise of Earth as an oscillator

[Bob Camp]

Hi


> On Jul 27, 2016, at 12:57 PM, Ron Ott  wrote:
> 
> There might be two Qs: one relating to the axil rotation and another 
> concerning the volume behavior of the earth as a giant bowl of Jello.  But 
> you'd have to figure out how to really slam the planet to excite the entire 
> volume. Earthquakes are probably too wimpy.

Run into a bit smaller Earth with an object somewhat larger than the moon?
Give us all a bit of a warning before you run the experiment so we can book 
that flight to Mars ...

Bob

> Ron
> 
> 
>  From: Chris Caudle 
> To: time-nuts@febo.com 
> Sent: Wednesday, July 27, 2016 8:50 AM
> Subject: Re: [time-nuts] Q/noise of Earth as an oscillator
> 
> On Wed, July 27, 2016 10:33 am, Chris Caudle wrote:
>> Does that imply that this value is not constant:
 And if you take the classic definition
 Q = 2 pi * total energy /energy lost per cycle
 then it would seem earth has a Q factor.
> 
> After re-reading "The Story of Q" I agree that Q of a rotating body could
> be non-constant, but also consistent with the original definition of Q as
> the ratio of reactance to resistance of an inductor, which of course would
> vary almost completely linearly over a wide frequency range where the
> resistive dissipation was not frequency dependent (i.e. where skin effect
> was negligible).
> 
> Perhaps a more useful question is whether that is still a useful
> definition compared to how the term is more typically used now to refer to
> resonance bandwidth.
> 
> -- 
> Chris Caudle
> 
> 
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> 
> 
> 
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Re: [time-nuts] Q/noise of Earth as an oscillator

[Tony Finch]

Neville Michie  wrote:

> The conical pendulum has a simple form of a weight on a string, instead
> of oscillating in one plane as a conventional pendulum, it swings around
> in a circular orbit in the horizontal plane. It has a definite resonant
> frequency.

I don't think it does have a resonant frequency, any more than the Earth
does: the angular velocity of the pendulum is sqrt(g/h) where h is the
height of the pendulum; give it more energy, it swings higher, so h is
smaller, so the frequency is higher.

Tony.
-- 
f.anthony.n.finch    http://dotat.at/  -  I xn--zr8h punycode
South Thames, Dover: Southwesterly 5 or 6. Slight or moderate. Rain or
showers. Good, occasionally poor.
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Re: [time-nuts] GPS receiver time message offsets to 1PPS (updated)

[Bob Camp]

Hi

So everything is inside a 10 ms sdev except:

UBLOX LEA-6T NMEA at 11.1 ms (Binary is much better) 
Adafruit Ultimate at 39.8 ms

Neither one of those are really surprising. NMEA is not the best thing on uBlox.
The specs on the Adafruit part have never made much sense for timing. Somebody
was a bit confused when they did (or at least spec’d)  that part. 

There is the Skylab SKM53 at 37.8 ms. I’ve never seen one of those, so no guess
about that one. 

The surprise in the crowd is the Res-T SMT at 63.7 ms. I wonder what they messed
up? 

Bob


> On Jul 27, 2016, at 10:13 PM, Mark Sims  wrote:
> 
> I found what was causing the apparent ramps in the message offset time for 
> the Motorola mode receivers and the Z38xx receivers.  Here is the updated and 
> corrected info.  Note that a couple of receivers do have some minor ramp 
> sawtooths in their message timing.  They are less than +/- 10 msecs from 
> nominal.
> 
> ---  
> 
> Here are the results of measuring the difference between the time code in a 
> GPS receiver time message and the arrival time of the last byte of the 
> message.  Negative values mean that the receiver sends the timing message 
> after the 1PPS pulse that it describes. The table also shows the standard 
> deviation of the message arrival times.
> 
> 
> The test configuration was a Compaq N610C laptop (2 GHz Pentium, hardware 
> serial port) running Linux Ubuntu Mate 15.10).  The time of the 
> messagearrival was from the system clock synced to NTP.  The receivers were 
> tested in native binary protocol and, if supported, NMEA.  The com port was 
> runningat the default value for the receiver.  If not specified that was 
> 9600:8:N:1Data was collected after the receiver had been tracking satellites 
> for at least 1 hour and averaged over 4 hours.  The timings were also checked 
> andagree with those on a Raspberry PI 3 and a quad-core 3 GHz box.
> 
> 
> Although measuring the arrival time of the first byte of the timing 
> messagemakes more technical sense (less variation due to timing message 
> length and baud rate) these measurements are of the last byte of the message. 
>  This was chosen to assist people trying to sync a clock to a GPS receiver 
> without relying on the 1PPS pulse.  They are also useful to people that want 
> to knowhow long they have to process a timing message (like to set a sawtooth 
> compensation delay line) before the next 1PPS pulse comes out.
> 
> 
> A few receivers appear to not fully sync their timing message to some 
> referenceclock.  This causes the timing message arrival time to follow a ramp 
> curve.The ramp size is fairly small (+/- 5 to 10 msecs) in most receivers.
> 
> 
> Device Protocol   Firmware   (msg-arrival)  sdev
>(msecs)
> =       =
> Thunderbolt TSIP App:3.0 GPS:10.2 -52.9  6.2   (gold box)
> Thunderbolt TSIP App:2.22 GPS:10.2-67.2 10.2   (red box)
> Resolution-TTSIP GPS:1.26-140.0  5.4
> Res-T SMT   TSIP GPS 2.7 -475.0 63.7
> Starloc II  TSIP App:1.10 GPS:1.2-267.5  7.2
> Trimble NTWx?   TSIP GPS 10.4 -44.9  1.2 
> Nortel NTPx TSIP GPS 10.1 -61.8  1.4
> Nortel NTGx TSIP GPS 10.5 -57.2  2.4
> 
> 
> Ublox LEA-6Tbinary6.02 (36023)   -242.7  4.4
> Ublox LEA-6TNMEA  6.02 (36023)   -198.7 11.1
> Ublox Neo6M binary7.03 (45969)   -211.6  9.3
> Ublox Neo6M NMEA  7.03 (45969)   -149.0  8.4
> Ublox 7 binary1.00 (59842)   -186.9  2.6
> Ublox 7 NMEA  1.00 (59842)   -152.9  7.9
> Ublox NEO-8Mbinary2.01 (75350)   -192.7  9.1
> Ublox NEO-8MNMEA  2.01 (75250)   -182.4  8.0
> 
> V.KEL SIRFIII   binaryGSW3.2.5   -432.8  6.1
> V.KEL SIRFIII   NMEA  GSW3.2.5   -427.6  5.0
> 
> Navspark Mini   Venus81.7.27 15.8.18 -139.3  7.1
> 
> Adafruit Ultimate  NMEA  -428.2 39.8
> 
> Skylab SKM53NMEA -492.0 37.8  (has short 
> jumps to usually -180)
> 
> Jupiter-T   Zodiac93.07 -1263.6  3.3
> Juptier-T   Motorola  93.07  -287.9  3.2 
> Jupiter PicoZodiac14.00 11/28/05-1235.5  0.4  (ramps 
> -1225 .. -1245 over 130 minutes)
> Jupiter PicoMotorola  14.00 11/28/05 -298.0  1.8 
> 
> Motorola UT+Motorola  R5122U1112 -258.2  3.7 
> Synergy M12+Motorola  P273T12T11 -194.8  1.4  
> 
> Z3812A  SCPI  X98-4-A 949.5  0.8  (ramps 945 
> .. 955 over 16 seconds)
> 

Re: [time-nuts] Q/noise of Earth as an oscillator

[Ron Ott]

There might be two Qs: one relating to the axil rotation and another concerning 
the volume behavior of the earth as a giant bowl of Jello.  But you'd have to 
figure out how to really slam the planet to excite the entire volume. 
Earthquakes are probably too wimpy.
Ron


  From: Chris Caudle 
 To: time-nuts@febo.com 
 Sent: Wednesday, July 27, 2016 8:50 AM
 Subject: Re: [time-nuts] Q/noise of Earth as an oscillator
   
On Wed, July 27, 2016 10:33 am, Chris Caudle wrote:
> Does that imply that this value is not constant:
>>> And if you take the classic definition
>>> Q = 2 pi * total energy /energy lost per cycle
>>> then it would seem earth has a Q factor.

After re-reading "The Story of Q" I agree that Q of a rotating body could
be non-constant, but also consistent with the original definition of Q as
the ratio of reactance to resistance of an inductor, which of course would
vary almost completely linearly over a wide frequency range where the
resistive dissipation was not frequency dependent (i.e. where skin effect
was negligible).

Perhaps a more useful question is whether that is still a useful
definition compared to how the term is more typically used now to refer to
resonance bandwidth.

-- 
Chris Caudle


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Re: [time-nuts] GPS receiver time message offsets to 1PPS (updated)

[Gary E. Miller]

Yo Mark!

On Thu, 28 Jul 2016 02:13:09 +
Mark Sims  wrote:

> I found what was causing the apparent ramps in the message offset
> time for the Motorola mode receivers and the Z38xx receivers. 

And the problem was?

RGDS
GARY
---
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
g...@rellim.com  Tel:+1 541 382 8588


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