> 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
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
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
-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
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
>
bo.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 wo
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 i
gt; - 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
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
>
&g
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
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
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
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).
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
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
e-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] Sta
, 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 quest
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
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
.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
-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
...@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
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
___
time-nuts mailing
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
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
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