Re: [time-nuts] State of the art of crystal oscillator measurements

[John Miles]

> If the oscillator output is thru the resonator, then at large offsets,
> the source impedance is reactive.  It can easily have an effective
> temperature less than room temperature.  If this "source" is then
> used with a low noise temperature preamp, it is entirely possible
> to go beyond these supposed theoretical limits that are based
> on T=300K.

Sure, until you try to measure it with a Zo=50R instrument, or otherwise do 
something that involves putting real power into a load.

-- john, KE5FX
Miles Design LLC


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Re: [time-nuts] State of the art of crystal oscillator measurements

[Richard (Rick) Karlquist]

On 8/11/2016 3:47 PM, John Miles wrote:

Right, I'm speaking specifically of L(f).  The device being driven by the 
oscillator doesn't care about the NF of the driver stage, only what a PN 
analyzer would measure at the output jack.

For any 50-ohm source, the practical L(f) floor is -177 dBm/Hz - the carrier 
power in dBm.  No oscillator with an output of 0 dBm can be quieter than -177 
dBc/Hz at any offset, but an oscillator that puts out +20 dBm could approach 
-197 dBc/Hz.

Given a proverbial black box containing a +17 dBm oscillator that measures -195 dBc/Hz at 
100 kHz, the interesting question is, "What's in the box?"  There could be a 
passive resonator that's shaving off the broadband noise after the last active stage 
without contributing additive noise of its own.  Another possibility might be 
cross-spectral collapse due to correlated thermal noise from the splitter.

-- john, KE5FX
Miles Design LLC



If the oscillator output is thru the resonator, then at large offsets,
the source impedance is reactive.  It can easily have an effective
temperature less than room temperature.  If this "source" is then
used with a low noise temperature preamp, it is entirely possible
to go beyond these supposed theoretical limits that are based
on T=300K.

Rick
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Re: [time-nuts] State of the art of crystal oscillator measurements

[KA2WEU--- via time-nuts]

-177dBm /Hz at 300 deg  SSB phase noise is correct, not because AM/  FM but 
Single Sideband Energy .
In my last QEX paper I showed the measured AM and FM levels and how to  
calculate them.
 
73 de Ulrich 
 

xx
 
 
In a message dated 8/11/2016 9:00:11 P.M. Eastern Daylight Time,  
mfe...@eozinc.com writes:

That is  interesting. We always used -174 and not -177 as it was concluded 
that at  those low levels AM and PM noise are not discernible, so, the total 
noise  density per Hz was -174. This must be relatively new since I worked 
in  industry. We had a bunch of PhDs from Lincoln helping as well and they 
always  used -174. This sounds like one of those instrument manufacturers 
gimmick to  make the numbers look better :). 

Your last statement is why I started  to question the claims initially. - 
Mike 

Mike B. Feher, EOZ Inc.
89  Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831  cell


-Original Message-
From: time-nuts  [mailto:time-nuts-boun...@febo.com] On Behalf Of John Miles
Sent: Thursday,  August 11, 2016 7:57 PM
To: 'Discussion of precise time and frequency  measurement'
Subject: Re: [time-nuts] State of the art of crystal  oscillator 
measurements

-177 = the -174 dBm/Hz SSB thermal noise floor  at 25C, less 3 dB to 
account for the usual assumption that half of it is AM,  half PM.   

dBm/Hz is obviously equivalent to dBc/Hz for a 0  dBm carrier.  

Anyone who claims to measure noise in a 1 Hz  bandwidth below -177 dBm/Hz 
at room temperature is either doing something  wrong somewhere, or doing 
something amazing somewhere.

-- john,  KE5FX
Miles Design LLC

> -Original Message-
> From:  time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Mike 
>  Feher
> Sent: Thursday, August 11, 2016 4:15 PM
> To: 'Discussion  of precise time and frequency measurement'
> Subject: Re: [time-nuts]  State of the art of crystal oscillator 
> measurements
> 
>  That is why I asked what the Po was. Where did the 177 come from? L(f)  
> is single sided. This is not my first "rodeo" in these matters. 73 -  
> Mike
> 
> Mike B. Feher, EOZ Inc.
> 89 Arnold  Blvd.
> Howell, NJ, 07731
> 732-886-5960 office
>  908-902-3831 cell
>  

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Re: [time-nuts] State of the art of crystal oscillator measurements

[Mike Feher]

That is interesting. We always used -174 and not -177 as it was concluded that 
at those low levels AM and PM noise are not discernible, so, the total noise 
density per Hz was -174. This must be relatively new since I worked in 
industry. We had a bunch of PhDs from Lincoln helping as well and they always 
used -174. This sounds like one of those instrument manufacturers gimmick to 
make the numbers look better :). 

Your last statement is why I started to question the claims initially. - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of John Miles
Sent: Thursday, August 11, 2016 7:57 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements

-177 = the -174 dBm/Hz SSB thermal noise floor at 25C, less 3 dB to account for 
the usual assumption that half of it is AM, half PM.   

dBm/Hz is obviously equivalent to dBc/Hz for a 0 dBm carrier.  

Anyone who claims to measure noise in a 1 Hz bandwidth below -177 dBm/Hz at 
room temperature is either doing something wrong somewhere, or doing something 
amazing somewhere.

-- john, KE5FX
Miles Design LLC

> -Original Message-
> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Mike 
> Feher
> Sent: Thursday, August 11, 2016 4:15 PM
> To: 'Discussion of precise time and frequency measurement'
> Subject: Re: [time-nuts] State of the art of crystal oscillator 
> measurements
> 
> That is why I asked what the Po was. Where did the 177 come from? L(f) 
> is single sided. This is not my first "rodeo" in these matters. 73 - 
> Mike
> 
> Mike B. Feher, EOZ Inc.
> 89 Arnold Blvd.
> Howell, NJ, 07731
> 732-886-5960 office
> 908-902-3831 cell
> 

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Re: [time-nuts] State of the art of crystal oscillator measurements

[John Miles]

-177 = the -174 dBm/Hz SSB thermal noise floor at 25C, less 3 dB to account for 
the usual assumption that half of it is AM, half PM.   

dBm/Hz is obviously equivalent to dBc/Hz for a 0 dBm carrier.  

Anyone who claims to measure noise in a 1 Hz bandwidth below -177 dBm/Hz at 
room temperature is either doing something wrong somewhere, or doing something 
amazing somewhere.

-- john, KE5FX
Miles Design LLC

> -Original Message-
> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Mike
> Feher
> Sent: Thursday, August 11, 2016 4:15 PM
> To: 'Discussion of precise time and frequency measurement'
> Subject: Re: [time-nuts] State of the art of crystal oscillator measurements
> 
> That is why I asked what the Po was. Where did the 177 come from? L(f) is
> single sided. This is not my first "rodeo" in these matters. 73 - Mike
> 
> Mike B. Feher, EOZ Inc.
> 89 Arnold Blvd.
> Howell, NJ, 07731
> 732-886-5960 office
> 908-902-3831 cell
> 

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Re: [time-nuts] State of the art of crystal oscillator measurements

[John Miles]

Good point, the 'milliwatt' part of 'dBm' takes the E^2/R part out of the math. 
 If we were speaking of dBv/Hz, the system Zo would need to be considered to 
determine the power.  

-- john, KE5FX
Miles Design LLC

> -Original Message-
> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Richard
> (Rick) Karlquist
> Sent: Thursday, August 11, 2016 3:01 PM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] State of the art of crystal oscillator measurements
> 
> Zo doesn't matter for these purposes.
> dBm works just as well for 75 ohm systems.
> 

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Re: [time-nuts] State of the art of crystal oscillator measurements

[Mike Feher]

That is why I asked what the Po was. Where did the 177 come from? L(f) is 
single sided. This is not my first "rodeo" in these matters. 73 - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of John Miles
Sent: Thursday, August 11, 2016 4:22 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements

Remember that L(f) is expressed in dBc/Hz, not dBm/Hz.  If it were dBm/Hz, then 
kT would be the limit.  But in dBc/Hz terms, the limit is 177 + the DUT's 
output power in dBm.  

Assuming a 50 ohm system, of course.

-- john, KE5FX
Miles Design LLC


> -Original Message-
> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Mike 
> Feher
> Sent: Thursday, August 11, 2016 12:51 PM
> To: 'Discussion of precise time and frequency measurement'; 
> ka2...@aol.com; t...@leapsecond.com
> Cc: enrico.rubi...@gmail.com
> Subject: Re: [time-nuts] State of the art of crystal oscillator 
> measurements
> 
> kT is indeed relevant for a physical implementation. - Mike
> 
> Mike B. Feher, EOZ Inc.
> 89 Arnold Blvd.
> Howell, NJ, 07731
> 732-886-5960 office
> 908-902-3831 cell

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Re: [time-nuts] State of the art of crystal oscillator measurements

[KA2WEU--- via time-nuts]

Values  of kT at 25°C (298 K) Units  kT = 4.11×10−21 _J_ 
(https://en.wikipedia.org/wiki/Joule)   kT = 4.114 pN⋅nm  kT = 9.83×10−22 _cal_ 
(https://en.wikipedia.org/wiki/Calorie)   kT = 25.7 _meV_ 
(https://en.wikipedia.org/wiki/Electron-volt)Related quantities  kT/hc = 
200 cm-1  kT/e = 25.7 _mV_ 
(https://en.wikipedia.org/wiki/Volt)   RT = kT ⋅ _NA_ 
(https://en.wikipedia.org/wiki/Avogadro's_number)  = 2.479 _kJ⋅mol-1_ 
(https://en.wikipedia.org/wiki/Joule_per_mole)   u = 0.593 _kcal⋅mol−1_ 
(https://en.wikipedia.org/wiki/Kilocalorie_per_mole)   _h_ 
(https://en.wikipedia.org/wiki/Planck_constant) 
/kT = 0.16 _ps_ (https://en.wikipedia.org/wiki/Picosecond) 
 
 
In a message dated 8/11/2016 7:02:13 P.M. Eastern Daylight Time,  
j...@miles.io writes:

Right,  I'm speaking specifically of L(f).  The device being driven by the  
oscillator doesn't care about the NF of the driver stage, only what a PN  
analyzer would measure at the output jack.

For any 50-ohm source, the  practical L(f) floor is -177 dBm/Hz - the 
carrier power in dBm.  No  oscillator with an output of 0 dBm can be quieter 
than 
-177 dBc/Hz at any  offset, but an oscillator that puts out +20 dBm could 
approach -197  dBc/Hz.

Given a proverbial black box containing a +17 dBm oscillator  that measures 
-195 dBc/Hz at 100 kHz, the interesting question is, "What's in  the box?"  
There could be a passive resonator that's shaving off the  broadband noise 
after the last active stage without contributing additive  noise of its own. 
 Another possibility might be cross-spectral collapse  due to correlated 
thermal noise from the splitter.   

--  john, KE5FX
Miles Design LLC


> -Original  Message-
> From: time-nuts [mailto:time-nuts-boun...@febo.com] On  Behalf Of KA2WEU--
> - via time-nuts
> Sent: Thursday, August 11,  2016 2:37 PM
> To: time-nuts@febo.com
> Subject: Re: [time-nuts]  State of the art of crystal oscillator 
measurements
> 
> NO, the  maximum  possible noise dynamic range is ( 177 +  Pout)   [dBm]  
-
> Transistor large signal NF ( dB),
>  the  signal to noise ration is dimensionless 
>  

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Re: [time-nuts] State of the art of crystal oscillator measurements

[John Miles]

Right, I'm speaking specifically of L(f).  The device being driven by the 
oscillator doesn't care about the NF of the driver stage, only what a PN 
analyzer would measure at the output jack.

For any 50-ohm source, the practical L(f) floor is -177 dBm/Hz - the carrier 
power in dBm.  No oscillator with an output of 0 dBm can be quieter than -177 
dBc/Hz at any offset, but an oscillator that puts out +20 dBm could approach 
-197 dBc/Hz.

Given a proverbial black box containing a +17 dBm oscillator that measures -195 
dBc/Hz at 100 kHz, the interesting question is, "What's in the box?"  There 
could be a passive resonator that's shaving off the broadband noise after the 
last active stage without contributing additive noise of its own.  Another 
possibility might be cross-spectral collapse due to correlated thermal noise 
from the splitter.   

-- john, KE5FX
Miles Design LLC


> -Original Message-
> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of KA2WEU--
> - via time-nuts
> Sent: Thursday, August 11, 2016 2:37 PM
> To: time-nuts@febo.com
> Subject: Re: [time-nuts] State of the art of crystal oscillator measurements
> 
> NO, the maximum  possible noise dynamic range is ( 177 +  Pout)  [dBm]  -
> Transistor large signal NF ( dB),
>  the signal to noise ration is dimensionless 
> 

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Re: [time-nuts] State of the art of crystal oscillator measurements

[Richard (Rick) Karlquist]

Zo doesn't matter for these purposes.
dBm works just as well for 75 ohm systems.

On 8/11/2016 1:22 PM, John Miles wrote:

Remember that L(f) is expressed in dBc/Hz, not dBm/Hz.  If it were dBm/Hz, then 
kT would be the limit.  But in dBc/Hz terms, the limit is 177 + the DUT's 
output power in dBm.

Assuming a 50 ohm system, of course.

-- john, KE5FX
Miles Design LLC



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Re: [time-nuts] State of the art of crystal oscillator measurements

[Bob Camp]

Hi

The gotcha is that you don’t *have* to have a 50 ohm system. An output stage 
with
a narrow band tuned tank is one example of a very “not 50 ohms” system. 

There is also a whole debate around the “is 50 ohm source into 50 ohm load 
really 25 ohms”. 
That will give you a 3 db delta to bet beers about. The 3 db split of thermal 
noise between AM
noise and PM noise is fairly well accepted, but it still can be challenged. 

So is the floor -174 - 3 = -177 or is it something else …. 

If we have a -195.4 dbc/ Hz oscillator that puts out < 18 dbm in a 50 ohm 
system it’s not -177 or
it’s not a 50 ohm system. 

Bob

> On Aug 11, 2016, at 4:47 PM, John Miles  wrote:
> 
> Or rather -(177+DUT output power in dBm).  The minus sign makes the 
> difference between the thermal floor and a nuclear war!
> 
> -- john, KE5FX
> Miles Design LLC
> 
>> Remember that L(f) is expressed in dBc/Hz, not dBm/Hz.  If it were dBm/Hz,
>> then kT would be the limit.  But in dBc/Hz terms, the limit is 177 + the 
>> DUT's
>> output power in dBm.
> 
> 
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Re: [time-nuts] State of the art of crystal oscillator measurements

[Tom Holmes]

I am quite intrigued by two things here:
1. What improvements were made to the instruments, and 

2. What were the instrument settings and test setups?

Thanks.

Tom Holmes, N8ZM


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of KA2WEU--- via 
time-nuts
Sent: Thursday, August 11, 2016 4:34 PM
To: time-nuts@febo.com
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements

See below 
 
 
In a message dated 8/11/2016 4:30:47 P.M. Eastern Daylight Time,  
j...@miles.io writes:

Remember  that L(f) is expressed in dBc/Hz, not dBm/Hz.  If it were dBm/Hz, 
then kT  would be the limit.  But in dBc/Hz terms, the limit  is 177 + the 
DUT's output power in dBm - transistor large signal NF in dB  .  

Assuming a 50 ohm system, of course.

-- john,  KE5FX
Miles Design LLC


> -Original Message-
>  From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Mike
>  Feher
> Sent: Thursday, August 11, 2016 12:51 PM
> To: 'Discussion  of precise time and frequency measurement';
> ka2...@aol.com;  t...@leapsecond.com
> Cc: enrico.rubi...@gmail.com
> Subject: Re:  [time-nuts] State of the art of crystal oscillator 
measurements
>  
> kT is indeed relevant for a physical implementation. - Mike
>  
> Mike B. Feher, EOZ Inc.
> 89 Arnold Blvd.
> Howell, NJ,  07731
> 732-886-5960 office
> 908-902-3831  cell

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Re: [time-nuts] State of the art of crystal oscillator measurements

[KA2WEU--- via time-nuts]

NO, the maximum  possible noise dynamic range is ( 177 +  Pout)  [dBm]  - 
Transistor large signal NF ( dB),
 the signal to noise ration is dimensionless 
 
 
In a message dated 8/11/2016 5:00:43 P.M. Eastern Daylight Time,  
j...@miles.io writes:

Or  rather -(177+DUT output power in dBm).  The minus sign makes the  
difference between the thermal floor and a nuclear war!

-- john,  KE5FX
Miles Design LLC

> Remember that L(f) is expressed in  dBc/Hz, not dBm/Hz.  If it were 
dBm/Hz,
> then kT would be the  limit.  But in dBc/Hz terms, the limit is 177 + the 
DUT's
> output  power in  dBm.


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Re: [time-nuts] State of the art of crystal oscillator measurements

[John Miles]

Or rather -(177+DUT output power in dBm).  The minus sign makes the difference 
between the thermal floor and a nuclear war!

-- john, KE5FX
Miles Design LLC

> Remember that L(f) is expressed in dBc/Hz, not dBm/Hz.  If it were dBm/Hz,
> then kT would be the limit.  But in dBc/Hz terms, the limit is 177 + the DUT's
> output power in dBm.


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Re: [time-nuts] State of the art of crystal oscillator measurements

[KA2WEU--- via time-nuts]

See below 
 
 
In a message dated 8/11/2016 4:30:47 P.M. Eastern Daylight Time,  
j...@miles.io writes:

Remember  that L(f) is expressed in dBc/Hz, not dBm/Hz.  If it were dBm/Hz, 
then kT  would be the limit.  But in dBc/Hz terms, the limit  is 177 + the 
DUT's output power in dBm - transistor large signal NF in dB  .  

Assuming a 50 ohm system, of course.

-- john,  KE5FX
Miles Design LLC


> -Original Message-
>  From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Mike
>  Feher
> Sent: Thursday, August 11, 2016 12:51 PM
> To: 'Discussion  of precise time and frequency measurement';
> ka2...@aol.com;  t...@leapsecond.com
> Cc: enrico.rubi...@gmail.com
> Subject: Re:  [time-nuts] State of the art of crystal oscillator 
measurements
>  
> kT is indeed relevant for a physical implementation. - Mike
>  
> Mike B. Feher, EOZ Inc.
> 89 Arnold Blvd.
> Howell, NJ,  07731
> 732-886-5960 office
> 908-902-3831  cell

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Re: [time-nuts] State of the art of crystal oscillator measurements

[John Miles]

Remember that L(f) is expressed in dBc/Hz, not dBm/Hz.  If it were dBm/Hz, then 
kT would be the limit.  But in dBc/Hz terms, the limit is 177 + the DUT's 
output power in dBm.  

Assuming a 50 ohm system, of course.

-- john, KE5FX
Miles Design LLC


> -Original Message-
> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Mike
> Feher
> Sent: Thursday, August 11, 2016 12:51 PM
> To: 'Discussion of precise time and frequency measurement';
> ka2...@aol.com; t...@leapsecond.com
> Cc: enrico.rubi...@gmail.com
> Subject: Re: [time-nuts] State of the art of crystal oscillator measurements
> 
> kT is indeed relevant for a physical implementation. - Mike
> 
> Mike B. Feher, EOZ Inc.
> 89 Arnold Blvd.
> Howell, NJ, 07731
> 732-886-5960 office
> 908-902-3831 cell

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Re: [time-nuts] State of the art of crystal oscillator measurements

[Mike Feher]

kT is indeed relevant for a physical implementation. - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Richard (Rick) 
Karlquist
Sent: Thursday, August 11, 2016 1:40 PM
To: Discussion of precise time and frequency measurement; ka2...@aol.com; 
t...@leapsecond.com
Cc: enrico.rubi...@gmail.com
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements



On 8/11/2016 5:01 AM, Mike Feher wrote:

> This may be a naive question, but, how can you achieve results that 
> are so close to, and sometimes at further out are below kT? Thanks & 
> 73 - Mike

> Mike B. Feher, EOZ Inc.
>

kT per see is not the relevant parameter.  It is the ratio between kT and 
signal level that determines the limit on phase noise.  Also, when you extract 
an oscillator signal through the resonator, then at offsets from the carrier, 
the resonator filters out noise and the output noise can be way below kT.  
Ulrich first published on this in 1977.  Earliest reference I know of.
I actually remember reading it in 1977.

The old HP608 signal generator routinely produced far out phase noise floor 
well below kT.  AFAIK, for this particular spec, it better than any other 
signal generator ever built.  What's the secret?  It has a tracking 
POST-selector filter that follows the oscillator when you turn the mechanical 
tuning knob.  There is a little tracking adjustment knob to peak it.  Not 
really magic.

Rick
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Re: [time-nuts] State of the art of crystal oscillator measurements

[Richard (Rick) Karlquist]

On 8/11/2016 5:01 AM, Mike Feher wrote:


This may be a naive question, but, how can you achieve results that are so
close to, and sometimes at further out are below kT? Thanks & 73 - Mike



Mike B. Feher, EOZ Inc.



kT per see is not the relevant parameter.  It is the
ratio between kT and signal level that determines the
limit on phase noise.  Also, when you extract an
oscillator signal through the resonator, then at offsets
from the carrier, the resonator filters out noise and
the output noise can be way below kT.  Ulrich first
published on this in 1977.  Earliest reference I know of.
I actually remember reading it in 1977.

The old HP608 signal generator routinely produced far
out phase noise floor well below kT.  AFAIK, for this
particular spec, it better than any other signal generator
ever built.  What's the secret?  It has a tracking
POST-selector filter that follows the oscillator when
you turn the mechanical tuning knob.  There is a little
tracking adjustment knob to peak it.  Not really magic.

Rick
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Re: [time-nuts] State of the art of crystal oscillator measurements

[David J Taylor]

Ulrich -

This may be a naive question, but, how can you achieve results that are so
close to, and sometimes at further out are below kT? Thanks & 73 - Mike 


Mike B. Feher, EOZ Inc.
===

.. by reducing T?

David
--
SatSignal Software - Quality software written to your requirements
Web: http://www.satsignal.eu
Email: david-tay...@blueyonder.co.uk
Twitter: @gm8arv
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Re: [time-nuts] State of the art of crystal oscillator measurements

[Mike Feher]

Ulrich -

 

This may be a naive question, but, how can you achieve results that are so
close to, and sometimes at further out are below kT? Thanks & 73 - Mike 

 

Mike B. Feher, EOZ Inc.

89 Arnold Blvd.

Howell, NJ, 07731

732-886-5960 office

908-902-3831 cell

 

From: ka2...@aol.com [mailto:ka2...@aol.com] 
Sent: Thursday, August 11, 2016 7:03 AM
To: time-nuts@febo.com; t...@leapsecond.com
Cc: enrico.rubi...@gmail.com; mfe...@eozinc.com
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements

 

Good morning,

 

the difference between the two phase noise FWSP systems is the lower noise
internal 10 MHz reference crystal  oscillator (optimized )  as well as also
some of the internal FSWP circuits custom  optimized . The output power was
17 dBm, but we also have build one oscillator with  12 dBm output power and
noise  similar values.

 

This is part of a PhD project which I supervise .   For values so close to
the carrier you need a very low noise power supply and a well shielded
Faraday cage . The measurement with ca 100  correlation took about 2 hours.
Also the heating circuit needs to be low noise and well decoupled .

 

The 100 Hz value of the better analyzer seems suspicious , It needs to be
further  investigated.

 

All very exciting and time consuming .

 

Ulrich 

 

 

 

 

 

In a message dated 8/10/2016 11:02:25 P.M. Eastern Daylight Time,
mfe...@eozinc.com writes:

These seem extremely fantastic results for a 100 MHz oscillator. I am
curious what the Po of the oscillators are Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tom Van
Baak
Sent: Wednesday, August 10, 2016 9:19 PM
To: Discussion of precise time and frequency measurement
Cc: enrico.rubi...@gmail.com
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements

Attached is a GIF of the table Ulrich wants to share.

Note time-nuts is a plain text mailing list so any rtf or html formatting is
discarded.
On the bright side, PDF or data or image attachments are allowed with no
problem.

/tvb

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Re: [time-nuts] State of the art of crystal oscillator measurements

[KA2WEU--- via time-nuts]

Good morning,
 
the difference between the two phase noise FWSP systems is the lower noise  
internal 10 MHz reference crystal  oscillator (optimized )  as  well as 
also some of the internal FSWP circuits custom  optimized . The  output power 
was 17 dBm, but we also have build one oscillator with  12 dBm  output power 
and noise  similar values.
 
This is part of a PhD project which I supervise .For values so close to 
the carrier you need a very low noise power supply  and a well shielded 
Faraday cage . The measurement with ca 100  correlation  took about 2 hours. 
Also the heating circuit needs to be low noise and well  decoupled .
 
The 100 Hz value of the better analyzer seems suspicious , It needs to be  
further  investigated.
 
All very exciting and time consuming .
 
Ulrich 
 
 
 
 
 
 
In a message dated 8/10/2016 11:02:25 P.M. Eastern Daylight Time,  
mfe...@eozinc.com writes:

These  seem extremely fantastic results for a 100 MHz oscillator. I am 
curious what  the Po of the oscillators are Regards - Mike 

Mike B. Feher, EOZ  Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960  office
908-902-3831 cell


-Original Message-
From:  time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tom Van  
Baak
Sent: Wednesday, August 10, 2016 9:19 PM
To: Discussion of precise  time and frequency measurement
Cc: enrico.rubi...@gmail.com
Subject: Re:  [time-nuts] State of the art of crystal oscillator  
measurements

Attached is a GIF of the table Ulrich wants to  share.

Note time-nuts is a plain text mailing list so any rtf or html  formatting 
is discarded.
On the bright side, PDF or data or image  attachments are allowed with no  
problem.

/tvb

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Re: [time-nuts] State of the art of crystal oscillator measurements

[Mike Feher]

These seem extremely fantastic results for a 100 MHz oscillator. I am curious 
what the Po of the oscillators are Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tom Van Baak
Sent: Wednesday, August 10, 2016 9:19 PM
To: Discussion of precise time and frequency measurement
Cc: enrico.rubi...@gmail.com
Subject: Re: [time-nuts] State of the art of crystal oscillator measurements

Attached is a GIF of the table Ulrich wants to share.

Note time-nuts is a plain text mailing list so any rtf or html formatting is 
discarded.
On the bright side, PDF or data or image attachments are allowed with no 
problem.

/tvb

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Re: [time-nuts] State of the art of crystal oscillator measurements

[Tom Van Baak]

Attached is a GIF of the table Ulrich wants to share.

Note time-nuts is a plain text mailing list so any rtf or html formatting is 
discarded.
On the bright side, PDF or data or image attachments are allowed with no 
problem.

/tvb
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Re: [time-nuts] State of the art of crystal oscillator measurements

[KA2WEU--- via time-nuts]

The _time-nuts@febo.com_ (mailto:time-nuts@febo.com)  reformatted the  
offset / phase noise  table so it became almost unreadable compared to the  
original , sorry, 
 
Ulrich 
 
 
In a message dated 8/10/2016 8:00:28 P.M. Eastern Daylight Time,  
time-nuts@febo.com writes:





Test Equipment Improvement 




The  measurement of  the  100 MHz  XO was done on an improved  R  FSWPs.  
Measured data is in the table  below:



XO  100  MHz   

FSWP SN  101143  
FSWP SN   101192   
Offset  
Phase  Noise in  dBc/Hz   
0.1  Hz  
-45.24   
-49.11   
1  Hz  
-82.30   
-82.33   
10  Hz  
-113.87   
-113.74   
100  Hz  
-143.27   
-141.61   
1  kHz  
-166.55   
-167.26   
10  kHz  
-180.54   
-186.91   
100  kHz  
-186.41  
-195.43  






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