more appropiate.
Best regards
Ulrich Bangert
-Ursprungliche Nachricht-
Von: time-nuts-boun...@febo.com
[mailto:time-nuts-boun...@febo.com] Im Auftrag von Hal Murray
Gesendet: Mittwoch, 3. Juni 2009 20:00
An: Discussion of precise time and frequency measurement
Betreff: Re: [time-nuts
Alberto di Bene skrev:
Magnus Danielson wrote:
Hmm, do you get a feeling that I am actually object very much to just
toss it into the processor. I think you are right. :)
I suppose you are familiar with the old American adage that says that to
a man with
a hammer every problem looks like
Lux, James P skrev:
-Original Message-
From: time-nuts-boun...@febo.com
[mailto:time-nuts-boun...@febo.com] On Behalf Of Rex Moncur
Sent: Tuesday, June 02, 2009 3:06 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] Sound Cards for locking to GPSDO
connie.marsh...@suddenlink.net said:
www.k5cm.com/soundcard.htm
Nice, thanks.
From there:
Sound card drift over this four hour period is about 250 micro Hertz.
The temp in the shack was going up during the measurement period.
Unfortunately I did not track the exact temp rise, but was about
One of the main problems is that in working at milli-Hz binwidths the
FTT word length needs to be very long to cover even a few tens of Hz
range and we run into memory problems.
I'm missing something. How much memory do you have on your laptop?
I'm not a DSP wizard. If you have 10 Hz
There is an overbeleif in what software is suitable for IMHO.
[Fun discussion. Thanks.]
Many years ago, somebody on the FPGA newsgroup pointed out that, in general,
if you can do the problem in software that's probably the better way. One of
the considerations is that it's easier to hire
-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on
Behalf Of Hal Murray
Sent: Wednesday, June 03, 2009 12:24 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Sound Cards for locking to GPSDO 10 MHz
references
connie.marsh...@suddenlink.net
Brian Kirby skrev:
I use a Lynx One sound card, it has analog and digital I/O and MIDI I/O
and clock I/O. Their manuals are available on line at
www.lynxstudio.com. These are profession 24 bit cards, the analog I/O
uses balanced interfaces. They handle AES/EBU and SP DIF digital audio
You could always transform this from a hardware problem to a software
problem. Take the output of your GPSDO, divide it down to somewhere
inside the audio band, feed it to a spare input on your USB sound
card and have software track this reference and correct the received
signal.
JDB.
--
Lux, James P skrev:
-Original Message-
From: time-nuts-boun...@febo.com
[mailto:time-nuts-boun...@febo.com] On Behalf Of Rex Moncur
Sent: Monday, June 01, 2009 3:00 PM
To: 'Discussion of precise time and frequency measurement'
Subject: [time-nuts] Sound Cards for locking to GPSDO 10
-Original Message-
From: time-nuts-boun...@febo.com
[mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson
Sent: Tuesday, June 02, 2009 10:08 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Sound Cards for locking to GPSDO 10
MHz
J.D. Bakker wrote:
You could always transform this from a hardware problem to a software
problem. Take the output of your GPSDO, divide it down to somewhere
inside the audio band, feed it to a spare input on your USB sound
card and have software track this reference and correct the received
Hello The Net:
For portable operations with a laptop, usually only one input channel is
available
and it is at mike (not line) level.
The alternative to sum the analog reference and the analog signal of
interest may be
possible if the reference noise can be kept out of the signal of
Lux, James P skrev:
-Original Message-
From: time-nuts-boun...@febo.com
[mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson
Sent: Tuesday, June 02, 2009 10:08 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Sound Cards for locking
Alberto di Bene skrev:
J.D. Bakker wrote:
You could always transform this from a hardware problem to a software
problem. Take the output of your GPSDO, divide it down to somewhere
inside the audio band, feed it to a spare input on your USB sound card
and have software track this reference and
Magnus Danielson wrote:
No need to switch on the soldering iron...
Never do in hardware what can be done in software :-)
Respectfully I disagree. There are tasks which is better managed by
software and tasks which is better managed by hardware. In the world of
FPGAs, it is also worth
Alberto di Bene skrev:
Magnus Danielson wrote:
No need to switch on the soldering iron...
Never do in hardware what can be done in software :-)
Respectfully I disagree. There are tasks which is better managed by
software and tasks which is better managed by hardware. In the world
of
Magnus Danielson wrote:
Hmm, do you get a feeling that I am actually object very much to just
toss it into the processor. I think you are right. :)
I suppose you are familiar with the old American adage that says that to a man
with
a hammer every problem looks like a nail :-)
Each of
Hi all
Thank you all for you advice and suggestions re my request. At this stage
it does not look like there is a simple solution of a readily available USB
sound card that can be locked to a 10 MHz GPSDO reference.
The constraints of portable operation with a Laptop rule out a number of
-Original Message-
From: time-nuts-boun...@febo.com
[mailto:time-nuts-boun...@febo.com] On Behalf Of Rex Moncur
Sent: Tuesday, June 02, 2009 3:06 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] Sound Cards for locking to GPSDO 10
MHz
Hi Rex,
Here is a plot of my sound card. Maybe I'm just lucky with this particular
sound card/computer, but the drift was only about 250 micro Hertz over a
four hour period. Also for critical measurements I try to run at 200 Hz
center frequency rather than 1000 Hz. Cuts the error by five. Maybe
Hi all
Does anyone have any experience of locking a USB external soundcard to a
GPSDO 10 MHz reference.
I am interested in advice on any good quality soundcards that can be readily
locked to either 10 MHz or if necessary to some other frequency that we can
derive from a GPSDO source. I have
Soundcards for USB are poor at best.
I have a set of PCI cards that were previously made by EMU and they accept
external reference input. They no longer make the model I have but perhaps
they have another PCI card with an external ref input.
I am interested in your modulation technique
...@bigpond.net.au
To: 'Discussion of precise time and frequency measurement'
time-nuts@febo.com
Sent: Monday, June 01, 2009 10:59 PM
Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz references
Hi all
Does anyone have any experience of locking a USB external soundcard to a
GPSDO 10 MHz
Hi Jeff
Thanks for your advice which I will follow up - the reason for going for a
USB sound card is that the system must be operated portable with a Laptop -
but perhaps there is a way to use a PCI sound card on a Laptop.
While we use WSJT at present we have a new Mode under development for the
rmon...@bigpond.net.au said:
For info the purpose of this request is that we are looking at using
very narrow bandwidth modes at less than 1 mHz for light wave
communcation. To date using LEDs and cloud reflection we have worked
over 200 km with WSJT but we should be able to do 20 dB better
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on
Behalf Of Jeffrey Pawlan
Sent: Monday, June 01, 2009 3:08 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Sound Cards for locking to GPSDO 10 MHz
references
-Original Message-
From: time-nuts-boun...@febo.com
[mailto:time-nuts-boun...@febo.com] On Behalf Of Rex Moncur
Sent: Monday, June 01, 2009 3:00 PM
To: 'Discussion of precise time and frequency measurement'
Subject: [time-nuts] Sound Cards for locking to GPSDO 10 MHz
references
I use a Lynx One sound card, it has analog and digital I/O and MIDI I/O
and clock I/O. Their manuals are available on line at
www.lynxstudio.com. These are profession 24 bit cards, the analog I/O
uses balanced interfaces. They handle AES/EBU and SP DIF digital audio
formats.
The sound
Demian Martin skrev:
Magnus Danielson wrote:
The digital link in question is S/PDIF; with the current popularity
of Home Theater systems cheap cards with digital I/O have become
quite prevalent. As an added bonus, S/PDIF can be run over both
coaxial and optical media, the latter being
Maybe I lost track and missed something, but I don't think I ever saw
more on the subject of specific high-end sound cards that might be
useful for nutty measurements.
From an earlier list message:
[F]or best noise/jitter-performance an external ADC should be used,
connected through a digital
J.D. Bakker skrev:
Maybe I lost track and missed something, but I don't think I ever saw
more on the subject of specific high-end sound cards that might be
useful for nutty measurements.
From an earlier list message:
[F]or best noise/jitter-performance an external ADC should be used,
Magnus Danielson wrote:
J.D. Bakker skrev:
Maybe I lost track and missed something, but I don't think I ever saw
more on the subject of specific high-end sound cards that might be
useful for nutty measurements.
From an earlier list message:
[F]or best
optical media, the latter being attractive in further isolating PC
noise from any measurement setup. And of course, a manufacturer's
evaluation board is much better documented and more suited to
measurement-specific mods than a random sound card.
The optical link commonly being used for
Lux, James P wrote:
I was amused when the guy at the stereo store tried to sell me on RF shielded
TOSlink cables, claiming it would provide more clarity and definition in the
sound. Uh-huh.. Sort of like the green marking pen for the edges of your
CDs to reduce internal reflections,
The optical link commonly being used for S/P-DIF is TosLink and it
seems like it can be the cause of many problems. It seems like some
care in doing the optical link setup is needed. I have never digged
into why the optical links have that problem. I can only guess, but
bad optical
At 10:30 +1300 14-01-2009, Bruce Griffiths wrote:
Magnus Danielson wrote:
J.D. Bakker skrev:
[F]or best noise/jitter-performance an external ADC should be used,
connected through a digital link to a PC sound card.[...]
The digital link in question is S/PDIF; with the current
John Ackermann N8UR wrote:
Lux, James P wrote:
I was amused when the guy at the stereo store tried to sell me on RF
shielded TOSlink cables, claiming it would provide more clarity and
definition in the sound. Uh-huh.. Sort of like the green marking pen for
the edges of your CDs to
Lux, James P skrev:
optical media, the latter being attractive in further isolating PC
noise from any measurement setup. And of course, a manufacturer's
evaluation board is much better documented and more suited to
measurement-specific mods than a random sound card.
The optical link commonly
Message-
From: time-nuts-boun...@febo.com
[mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson
Sent: Tuesday, January 13, 2009 3:01 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Sound cards
L
Consumer audio optical links (TOSlink
The optical link commonly being used for S/P-DIF is TosLink and it
seems like it can be the cause of many problems. It seems like some
care in doing the optical link setup is needed. I have never digged
into why the optical links have that problem. I can only guess, but
bad optical
Spoil sport!
Daun
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of John Ackermann N8UR
Sent: Tuesday, January 13, 2009 4:51 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Sound cards
Lux, James P
Magnus Danielson wrote:
The digital link in question is S/PDIF; with the current popularity
of Home Theater systems cheap cards with digital I/O have become
quite prevalent. As an added bonus, S/PDIF can be run over both
coaxial and optical media, the latter being attractive in further
From: time-nuts-boun...@febo.com
[mailto:time-nuts-boun...@febo.com] On Behalf Of Hal Murray
Sent: Tuesday, January 13, 2009 3:24 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Sound cards
I haven't worked with plastic fibers. I'd expect
Firecomm.com has some nice parts to look at
--- On Tue, 1/13/09, Demian Martin demi...@attglobal.net wrote:
From: Demian Martin demi...@attglobal.net
Subject: Re: [time-nuts] Sound Cards
To: time-nuts@febo.com
Date: Tuesday, January 13, 2009, 4:05 PM
Magnus Danielson wrote:
The digital link
Steve
Do you mean?:
http://www.firecom.com/
Bruce
steve heidmann wrote:
Firecomm.com has some nice parts to look at
--- On Tue, 1/13/09, Demian Martin demi...@attglobal.net wrote:
From: Demian Martin demi...@attglobal.net
Subject: Re: [time-nuts] Sound Cards
To: time-nuts@febo.com
Date
John Ackermann wrote:
One very interesting possibility is the HPSDR (High Performance
Software Defined Radio) boards called Ozy and Janus.
I'm not aware of anyone using this system for TF work, but it has some
interesting possibilities.
I bought mine for tf work, but sadly I have not
In the uber-thread Sub Pico Second Phase logger, this exchange took
place on 12/16:
Bruce Griffiths wrote:
Joseph M Gwinn wrote:
time-nuts-boun...@febo.com wrote on 12/15/2008 06:42:59 PM:
I've also looked at the specs for several other high end sound cards.
Quite a few only have
Rex said the following on 01/09/2009 06:37 AM:
Maybe I lost track and missed something, but I don't think I ever saw
more on the subject of specific high-end sound cards that might be
useful for nutty measurements.
I'd be interested to hear what any of the group has to share about
I've been using a Edirol FA-66, a firewire box with two balanced inputs
plus four more unbalanced. I think it can handle 192ks/24bit on 4
channels. A lot of hams use it for software defined radios, but I just
know it has better sound, especially the lows, for playing MP3s compared
to most
Eric Williams wrote:
I've been using a Edirol FA-66, a firewire box with two balanced inputs
plus four more unbalanced. I think it can handle 192ks/24bit on 4
channels. A lot of hams use it for software defined radios, but I just
know it has better sound, especially the lows, for playing
Rex wrote:
In the uber-thread Sub Pico Second Phase logger, this exchange took
place on 12/16:
Bruce Griffiths wrote:
Joseph M Gwinn wrote:
time-nuts-boun...@febo.com wrote on 12/15/2008 06:42:59 PM:
I've also looked at the specs for several other high end sound cards.
John
John Ackermann N8UR wrote:
Rex said the following on 01/09/2009 06:37 AM:
Maybe I lost track and missed something, but I don't think I ever saw
more on the subject of specific high-end sound cards that might be
useful for nutty measurements.
I'd be interested to hear what any of
53 matches
Mail list logo
