Foe word rate generation from 10 MHz, perhaps the TAPR devices:
http://www.tapr.org/kits_clock-block.html
or:
http://www.tapr.org/kits_tadd-2.html
with a type D f/f to get a square wave?
generate your clock for cheap.
Don
Chris Albertson
> There is a profesional "standard" for clock distribution f
azelio.bori...@screen.it said:
[couple some 1-pps energy into the signal being digitized]
> Yes, very smart, this analog time-stamping approach.
There is another trick you can use in this area.
If you can watch a PPS signal, you can figure out the frequency of the clock
used by the A/D system.
There is a profesional "standard" for clock distribution for computer audio
interfaces. They call it a "Word Clock" and it is usually distributed over
75 ohm coax cable. It is common for a studio to have a master word clock
generator and to use audio interfaces that accept an external clock. So
On 07/06/2012 06:57 PM, Azelio Boriani wrote:
The integer greatest common divisor 10MHz/25.576MHz is 16KHz so a simple
PLL should go through that frequency.
There are off the shelf products which accepts among others 10 MHz and
produces the suitable sync signals for audio, video and what have
On 07/06/2012 05:09 PM, Jim Lux wrote:
On 7/6/12 7:51 AM, Azelio Boriani wrote:
Yes, I'm also interested in how-to. At the moment I think it is a hack:
there is no sound card AFAIK that accepts a reference input. I have
recently bought an Acqiris/Agilent DP105/U1067A 150MHz 500Ms/s digitizer
PCI
On 07/06/2012 04:58 PM, John Ackermann N8UR wrote:
I think a number of higher-end sound cards accept a "word clock" or
"world clock" (I've seen it both ways) that's intended to allow syncing
to an external source. The challenge I've seen is that the frequency
(either in the 12 or 24 MHz range) is
Yes, very smart, this analog time-stamping approach.
On Sat, Jul 7, 2012 at 12:36 AM, John Miles wrote:
>
>
> > -Original Message-
> > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
> > Behalf Of Azelio Boriani
> > Sent: Friday, July 06, 2012 2:36 PM
> > To: Disc
> -Original Message-
> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
> Behalf Of Azelio Boriani
> Sent: Friday, July 06, 2012 2:36 PM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] disciplining sound card
>
> Exactly: this
Exactly: this prevented me to buy the ESI Juli@ sound card. It was
suggested by a fellow time-nut and this card is indeed very interesting but
in my opinion sound cards are not well defined about the sampling process.
I need more details. The Juli@ has the greater than usual bandwidth, not
limited
The trick here is the 50% divide-by-5, as you can see rather strange but
needed for the XOR.
On Fri, Jul 6, 2012 at 11:14 PM, Azelio Boriani wrote:
> OK, here the VHDL of the 24.576MHz synchronizer:
>
>
> LIBRARY IEEE;
> USE IEEE.std_logic_1164.ALL;
> USE IEEE.std_logic_unsigned.ALL;
> ENTITY FRS
OK, here the VHDL of the 24.576MHz synchronizer:
LIBRARY IEEE;
USE IEEE.std_logic_1164.ALL;
USE IEEE.std_logic_unsigned.ALL;
ENTITY FRSync IS
PORT (ClkIN, RefIN: IN std_logic; -- ClkIN is 24.576MHz/1536->16KHz, RefIN
is 10MHz/625->16KHz
PWMOut: OUT std_logic);
END ENTITY FRSync;
ARCHITECTURE Proc
With an oversampled ADC (which virtually all soundcards use these days),
do you really know when a sample was taken?
For the traditional ADC that used a sample and hold followed by
successive approximation, you knew the moment of sampling. For MASH
converters, I'm not so sure.
For high accur
Tristan.. I tried to contact you during my searches and I couldn't get
through.. something to do with the captcha. Your project is the only one I
saw that seemed applicable. I would like to know your progress.
--
Doc
Bill Dailey
KXØO
___
time-nuts ma
Another option is to do it yourself, it is one of my projects that is currently
in progress. I have some early information at:
http://electronics.ozonejunkie.com/category/electronics/time/10mhzaudio/
I am aware that the jitter will not be all that low, but I was more interested
in longer term s
It is very simple: let me describe it first. Two dividers and an XOR gate.
This is an FLL and only the frequency consistency is guaranteed but in this
case is enough. The advantage is that only a CPLD is used. I'll send the
VHDL so that it will be possible to use any CPLD. It is possible to
impleme
I'd suggest hacking USB type soundcards. It is certainly easier to get at the
guts.
There is a Chinese card peddled by a few vendors on ebay that comes in a blue
metal case. You can slip out the PCB. The card uses CMedia chips.
This is the first one I spotted on ebay:
http://item.mobileweb.eb
What if I post a schematic with a Lattice M4-64/32 CPLD? If you can program
this CPLD I can send the .JED file, the schematic...
-
I could probably get that done... would have to get a board made... never
done it but could probably manage...some kind of usb blaster
What if I post a schematic with a Lattice M4-64/32 CPLD? If you can program
this CPLD I can send the .JED file, the schematic...
On Fri, Jul 6, 2012 at 7:07 PM, Bill Dailey wrote:
> Yes, that i know. Just don't have the wherewithal to implement that
> myself.
>
>
> The integer
Yes, that i know. Just don't have the wherewithal to implement that myself.
The integer greatest common divisor 10MHz/25.576MHz is 16KHz so a simple
PLL should go through that frequency.
Sent from my iPhone
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time-nuts mailing list
The integer greatest common divisor 10MHz/25.576MHz is 16KHz so a simple
PLL should go through that frequency.
On Fri, Jul 6, 2012 at 6:38 PM, Bill Dailey wrote:
> Tips on this process if anyone wants to do this. From the cards I have
> there are 2 different types of oscillators/resonators... o
A balloonist realized he was lost. He descended and spotted a man on the
ground. He shouted down:
"Excuse me, can you help me? I promised a friend I would meet him half an
hour ago, but I don't know where I am."
The man on the ground replied, "You're at 42° 24.5' North latitude, 71°
11.3' West
Tips on this process if anyone wants to do this. From the cards I have
there are 2 different types of oscillators/resonators... one is SMD with 4
pads and the other was a through hole crystal. The right sided hole when
reading the label is the one you want.. With the SMD (most of the
oscillators
OK, I'll take a look at my cheap audio cards searching for the oscillator.
On Fri, Jul 6, 2012 at 5:59 PM, Bill Dailey wrote:
>
> Removed the oscillator and send it the required freq (24.576MHz) that is
> disciplined to 10MHz. Put an sma connector next to the card in the little
> cover on the p
Removed the oscillator and send it the required freq (24.576MHz) that is
disciplined to 10MHz. Put an sma connector next to the card in the little
cover on the pci slot. Currently using my ds345 but am getting a Valon
Synthesizer board with a divider. Tried ve1alq but the dividers aren't rig
A few cards accept a reference clock in the MHz range (usually under the term
"Superclock"), but most wordclock inputs are made for the wordclock frequency
itself, for example 48 kHz. An internal PLL (of varying quality) multiplies
that up to a multiple of it for driving the converter and shift
On 7/5/2012 9:42 PM, Sam Reaves wrote:
Does anyone know if there are any mods for these receivers for when WWVB
changes their modulation format?
Is the WWVB change a done deal? It makes no sense to me to change this
format as most people that carry a cell phone don't need a watch (nor wear
one)
On 7/5/2012 9:42 PM, Sam Reaves wrote:
Does anyone know if there are any mods for these receivers for when WWVB
changes their modulation format?
Is the WWVB change a done deal? It makes no sense to me to change this
format as most people that carry a cell phone don't need a watch (nor wear
one)
On 7/5/2012 11:02 PM, David I. Emery wrote:
On Thu, Jul 05, 2012 at 04:19:25PM -0700, J. Forster wrote:
If propagation goes south, you loose track of the carrier phase, the basis
of the system. If your local standard is stable and close to right, that's
not a big deal. If not, you can easily go
I don't know if they've been discontinued, but a number of the M-Audio
cards had word clock inputs as well. They are/were pretty widely
available on eBay.
John
On 7/6/2012 11:24 AM, Azelio Boriani wrote:
OK, found it: the RME HDSPe RayDAT PCIe audio card has this reference but
with the opti
Hi
My *guess* is that $50 is in the ball park for parts cost of a pretty good
receiver for the new format. That does not include things like the external
standard, antenna, frequency comparison stuff, power or case. I'd bound the
range of the guess as $25 to $100.
Bob
On Jul 5, 2012, at 11:5
> I think a number of higher-end sound cards accept a "word clock" or "world
> clock" (I've seen it both ways) that's intended to allow syncing to an
> external source. The challenge I've seen is that the frequency (either in
> the 12 or 24 MHz range) is one that's not simple to synthesize pr
Lets see if this comes through. Not sure gmail is sending.
As John has mentioned we have been working on this and I have concluded
that something needs to keep the local oscillator in 1/2 of the cycle.
Hate going back to some vco approach. But that seems to be the case.
Tried forcing the miller
Word clock generators appear to exist that will accept standard external
reference frequencies. One of the vendors also sells a stand alone 10 MHz
rubidium reference for driving their word clock generator.
Sent from my iPod
On 2012-07-06, at 8:09 AM, Jim Lux wrote:
> On 7/6/12 7:51 AM, Azel
OK, found it: the RME HDSPe RayDAT PCIe audio card has this reference but
with the optional extension card (of course). It is $950 for the card + the
expansion card for the world clock...
On Fri, Jul 6, 2012 at 5:09 PM, Jim Lux wrote:
> On 7/6/12 7:51 AM, Azelio Boriani wrote:
>
>> Yes, I'm also
On 7/6/12 7:51 AM, Azelio Boriani wrote:
Yes, I'm also interested in how-to. At the moment I think it is a hack:
there is no sound card AFAIK that accepts a reference input. I have
recently bought an Acqiris/Agilent DP105/U1067A 150MHz 500Ms/s digitizer
PCI card that accepts an external 10MHz as
On 7/6/12 7:51 AM, Azelio Boriani wrote:
Yes, I'm also interested in how-to. At the moment I think it is a hack:
there is no sound card AFAIK that accepts a reference input. I have
recently bought an Acqiris/Agilent DP105/U1067A 150MHz 500Ms/s digitizer
PCI card that accepts an external 10MHz as
I think a number of higher-end sound cards accept a "word clock" or
"world clock" (I've seen it both ways) that's intended to allow syncing
to an external source. The challenge I've seen is that the frequency
(either in the 12 or 24 MHz range) is one that's not simple to
synthesize precisely (
Yes, I'm also interested in how-to. At the moment I think it is a hack:
there is no sound card AFAIK that accepts a reference input. I have
recently bought an Acqiris/Agilent DP105/U1067A 150MHz 500Ms/s digitizer
PCI card that accepts an external 10MHz as a reference for the sampling
process.
On F
... and running it to a sound card (oscillator gps disciplined)
How did you achieve this?
Thanks
Stewart
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On 7/5/12 10:45 PM, Robert Atkinson wrote:
Hi Ed,
It's not just just "cheap and nasy" regens that cause this problem. Some
aircraft navigation and communication receivers where found to have enough local
oscillator harmonic leakage at 1575 MHz through the antenna port to jam GPS then tuned
to
Yes, the 433MHz is the ISM bande here in Europe and, when introduced, the
industry started to use SAW resonators so the emissions are now cleaner
than in the past.
On Fri, Jul 6, 2012 at 7:45 AM, Robert Atkinson wrote:
> Hi Ed,
> It's not just just "cheap and nasy" regens that cause this problem.
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