Subsequent measurements using an improved technique has allowed the true
flicker phase noise characteristics of a pair of OPA653 opamps to be
determined.
Opamp
Gain 1x (6db folled by 6 db attenuator consisting of a 50 ohm
resistor in series with the output of the opamp and the 50 ohm
Very good. I'm fascinated by the figures... how can such phase noise levels
be measured and, in general, being able to sense the most faint signal.
On Tue, Apr 17, 2012 at 11:25 AM, Bruce Griffiths
bruce.griffi...@xtra.co.nz wrote:
Subsequent measurements using an improved technique has
Good, the HP54720. We have one but, unfortunately, lost the calibration
(backup battery dead). Now it need the HP51717 to complete the calibration.
So be warned not to let the backup battery go flat: replace it trying to
supply, with a diode, the NVRAM.
On Tue, Apr 17, 2012 at 7:01 AM,
There are many ways to achieve a reasonably low phase noise floor when
measuring the additive phase noise of amplifiers etc:
1) Use an interferometer to null the carrier and amplify the
interferometer output being careful to ensure that the residual carrier
at the output of the amplifier isnt
Hi
Did you do any temperature stabilization on the op amps?
Bob
On Apr 17, 2012, at 5:25 AM, Bruce Griffiths wrote:
Subsequent measurements using an improved technique has allowed the true
flicker phase noise characteristics of a pair of OPA653 opamps to be
determined.
Opamp
Gain
Not yet, I just used the pair of TI evaluation boards which I obtained
for another project.
I intend to mount the various components (splitters, 180 degree hybrids
etc) on a thick aluminium plate to improve the mechanical and thermal
stability of the system.
Bruce
Bob Camp wrote:
Hi
Did
I quite like the HP 546xx series 'scopes. An analog like interface but good
DSO facilities. My regular 'scope at home is a 54645D mixed signal. Ideal for
lower speed logic/anlog circuits and 8 bit PICs. Takes up a lot less space than
a 16500x logic analyser! I still keep an older analog 'scope
Hi
My *guess* is that your 1Hz data may be as much from ambient changes as from
the op amps themselves. No data to back that up on these specific parts, just a
guess.
Bob
On Apr 17, 2012, at 7:28 AM, Bruce Griffiths wrote:
Not yet, I just used the pair of TI evaluation boards which I
I see the Trimble Resolution SMT Timing GPS OEM board 66974-35 on a
well-known auction site from a weel-know seller fluke.i, at quite a good
price, and free UK post. Is it any good - as good it seems to be. Any
experience?
Thanks,
David
--
SatSignal software - quality software written to
OK, I'll follow the Enrico Rubiola/TSC5120 literature.
On Tue, Apr 17, 2012 at 1:39 PM, Bob Camp li...@rtty.us wrote:
Hi
My *guess* is that your 1Hz data may be as much from ambient changes as
from the op amps themselves. No data to back that up on these specific
parts, just a guess.
Bob
I'll try shielding from air currents (usually effective to a little
below 1Hz).
The Opamp is thermally connected (metal tab under package is soldered
to) to one of the power planes so the thermal time constant is a little
longer than it would otherwise be.
Bruce
Bob Camp wrote:
Hi
My
I agree that memory depth is an under appreciated parameter, but even 2,500
points like what's available on the cheap Tek scopes is quite useful.
On the other hand, I had a few LeCroy with 50k deep memories and there are
cases where that is very useful too. I can't imagine real life use cases
I need lots of memory on scopes. A buddy of mine I worked with in the
ultrasound world actually yelled at the Tek product management and
asked if they actually *use* oscilloscopes. The answer was a sheepish
no, and yet they felt qualified to develop the products for the
company.
The cheap
On 4/17/12 6:56 AM, shali...@gmail.com wrote:
I agree that memory depth is an under appreciated parameter, but even 2,500
points like what's available on the cheap Tek scopes is quite useful.
On the other hand, I had a few LeCroy with 50k deep memories and there are
cases where that is very
On 4/17/12 7:15 AM, Robert Darlington wrote:
I need lots of memory on scopes. A buddy of mine I worked with in the
ultrasound world actually yelled at the Tek product management and
asked if they actually *use* oscilloscopes. The answer was a sheepish
no, and yet they felt qualified to develop
IMO, memory depth is like trying to do CAD on a standard computer
monitor... you keep having to switch between the local and global views
to do really anything. I find it annoying in the extreme.
IMO, you need enough memory depth so that you don't get artifacts, like
those in the pics I posted.
I need lots of memory on scopes. A buddy of mine I worked with in the
ultrasound world actually yelled at the Tek product management and
asked if they actually *use* oscilloscopes. The answer was a sheepish
no, and yet they felt qualified to develop the products for the
company.
Yeah!!
Sometime, just for fun, I'd like to get a Tek sales 'engineer' in to demo
his latest, hideously expensive, digital toy and compare the display to a
453 from 1965 on a WW II LORAN-A simulator that works with- gasp- vacuum
tubes.
Just for laughs, of course.
-John
==
On 4/17/12
One feature of the Agilent and Rohde scopes (maybe Tek, too?) that can help in
some situations is segmented memory. It allows you to capture periodic or
random events with the full sample rate but to ignore all the dead time between
events. For each trigger it stores one sweep with a time
Must be the reason behind the puzzling menus of Microsoft Office 2007 and up...
Everything requires one or two more clicks than the 2003 vintage.
Didier KO4BB
Sent from my BlackBerry Wireless thingy while I do other things...
-Original Message-
From: Scott McGrath scmcgr...@gmail.com
Hi
Tossing a beach towel over it usually does a pretty good job out to 10
seconds.
Bob
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bruce Griffiths
Sent: Tuesday, April 17, 2012 8:46 AM
To: Discussion of precise time and frequency
I have a Piezo 10mHz OCXO Model 2940210. If one of you has the pin-out for it,
I'd appreciate a copy or a source.
73,
Bud
w0lcp
Time is only there to prevent
everything from happening at once.
Einstein
___
time-nuts mailing list --
Please, please, do not tell stories like that regarding the radar to be used
to land on Mars. It makes me feel so sad, and my life so uninteresting...
That was a joke, I want more of that !!
By the way, I was trying to keeping it secret but as Robert just explained,
the Agilent 546XX are
Haven't run into that battery problem.. but rented the 51717 from an Ebay
offerer for low $$ in the past.
I simply sent him an email saying, I see you are selling that unit in your
ebay store, can I rent it from you for a week?
And he did..
I did have a power supply go bad, and simply
On 04/17/2012 06:06 PM, Bob Camp wrote:
Hi
Tossing a beach towel over it usually does a pretty good job out to 10
seconds.
Wet or dry towel? (Sorry could not refuse)
Actually, I'm happy to see that someone would try the interferometer
method. I've never come around to it, but understood
True, the LeCroy I have has +/- trigger, which is sometimes invaluable and very
hard to emulate if your scope does not have that feature.
Didier KO4BB
Sent from my BlackBerry Wireless thingy while I do other things...
-Original Message-
From: Tom Knox act...@hotmail.com
Date: Tue, 17
Right. I'll try to do the same: locating a 54717 to rent.
On Tue, Apr 17, 2012 at 8:52 PM, saidj...@aol.com wrote:
Haven't run into that battery problem.. but rented the 51717 from an Ebay
offerer for low $$ in the past.
I simply sent him an email saying, I see you are selling that unit in
Hi
For what ever reason I've always used a dry towel. I suspect it would also
do pretty well wet...
Bob
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Magnus Danielson
Sent: Tuesday, April 17, 2012 2:54 PM
To: time-nuts@febo.com
On Tue, 17 Apr 2012 01:01:49 -0400 (EDT)
saidj...@aol.com wrote:
It's a bit more than a Rigol, but for around $2200 you can get the
mainframe, two 21A plug ins, three FET probes, and as a side-feature the use
as a
boat anchor..
The problem for me is, that those are not available in
On 4/17/12 7:55 AM, John Lofgren wrote:
One feature of the Agilent and Rohde scopes (maybe Tek, too?) that can help in
some situations is segmented memory. It allows you to capture periodic or
random events with the full sample rate but to ignore all the dead time between
events. For each
On Tue, 17 Apr 2012 17:22:30 -0400
Bob Camp li...@rtty.us wrote:
For what ever reason I've always used a dry towel. I suspect it would also
do pretty well wet...
If you ever get around in measuring the difference between a dry and
a wet towel, i'd be interested in that :-)
Timestamp is good, but ping-pong circular buffers let you look at
precoursers to the trigger event if any, and loads one buffer at a time
to mass storage with accompanying metadata, including the timestamp.
Jim Lux
On 4/17/12 7:55 AM, John Lofgren wrote:
One feature of the Agilent and Rohde
You can buy Rigol from Chinese vendors on ebay. It doesn't pay to do
this in the US since they are well distributed, but I have read posts on
sci.engineering.design about direct from China purchases.
On 4/17/2012 3:22 PM, Attila Kinali wrote:
On Tue, 17 Apr 2012 01:01:49 -0400 (EDT)
Almost worth flying to NYC for the weekend from Switzerland and checking in the
scope as luggage on way back..
Sent From iPhone
On Apr 17, 2012, at 15:22, Attila Kinali att...@kinali.ch wrote:
On Tue, 17 Apr 2012 01:01:49 -0400 (EDT)
saidj...@aol.com wrote:
It's a bit more than a Rigol,
John
I wonder what that same engineer would think when I used to link 2 453's
together when trouble shooting problems on and optical character reader
using a crt and pmt's to scan the document.
Pardon my ignorance but what is deep memory? Please have mercy, I come
from the days of 64k was
John
I wonder what that same engineer would think when I used to link 2 453's
together when trouble shooting problems on and optical character reader
using a crt and pmt's to scan the document.
A Flying Spot scanner is entirely legitimate. I'd use a 600 series monitor
though. There ia a Dutch
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