On 25.04.2020 12:19, Hal Murray wrote:
David Taylor said:
With those recommendations, and noting the delays in RPi I/O (at least in
the earlier RPi cards where Ethernet is over USB), I would suggest that an
OCXO is overkill. No reason to deviate from the Raspbian OS.
That's an important poin
On Montag, 27. April 2020 08:47:45 CEST Hal Murray wrote:
> You could also use the Pi for the microcontroller. There is an API to the
> Kernel timekeeping routines. Try man ntp_adjtime. There are 2 knobs. One
> is to adjust the speed of the clock, aka correct for the drift. The other
> is to a
On Sat, Apr 25, 2020 at 03:19:54AM -0700, Hal Murray wrote:
>
> David Taylor said:
> > With those recommendations, and noting the delays in RPi I/O (at least in
> > the earlier RPi cards where Ethernet is over USB), I would suggest that an
> > OCXO is overkill. No reason to deviate from the Raspb
> I was basically planning on feeding the OCXO and the PPS from a GPS module
> into a simple microcontroller.
If you feed the PPS from a GPS into a microconroller, you can work out the
clock speed on the microcontroller.
If you feed the serial signal from the GPS into the microcontroller, you
Would you care to share what you did? I found this online. It looks
interesting. Maybe nothing more than a fun project. Seems to be a lot of debate
on how effective it is. I'm a novice at this stuff so I don't have any value to
add on it's effectiveness...
https://raspberrypi.stackexchange.com
On Fri, Apr 24, 2020 at 04:10:46PM -0700, Hal Murray wrote:
> > Is this a reasonable setup for an affordable NTP server?
>
> How/where are you going to connect up the OCXO?
>
I was basically planning on feeding the OCXO and the PPS from a GPS
module into a simple microcontroller. Using a capture
On Freitag, 24. April 2020 20:46:25 CEST Andreas Kempe wrote:
> I want to build an affordable quality time source for my computer
> club. I've been toying with the idea of using an oven controlled
> oscillator from Ebay for getting a reasonable (0,5 ppm frequency
> stability) 1 PPS signal and a che
David Taylor said:
> With those recommendations, and noting the delays in RPi I/O (at least in
> the earlier RPi cards where Ethernet is over USB), I would suggest that an
> OCXO is overkill. No reason to deviate from the Raspbian OS.
That's an important point. Thanks David. I'm embarrassed
Regarding the temperatur sensitivity of the raspberrypi, i have replaced the
xtal on several if them by a tcxo. This a hell of a difference.
Kind regards,
Stijn Nestra
Verstuurd vanaf mijn iPhone
> Op 25 apr. 2020 om 09:47 heeft David J Taylor via time-nuts
> het volgende geschreven:
>
>
From: Andreas Kempe
Hello everyone,
I want to build an affordable quality time source for my computer
club. I've been toying with the idea of using an oven controlled
oscillator from Ebay for getting a reasonable (0,5 ppm frequency
stability) 1 PPS signal and a cheap GSP chip with UART for synci
> Is this a reasonable setup for an affordable NTP server?
How/where are you going to connect up the OCXO?
> I want to build an affordable quality time source for my computer club.
Assuming "time source" means NTP server, the CPU is where you want to connect
up a good clock. You will probably
Hi
A GPSDO would be the “next step” if you want to continue on when GPS
is not present. They are a < $100 sort of thing from a number of sources.
Bob
> On Apr 24, 2020, at 4:38 PM, Andreas Kempe wrote:
>
> On Fri, Apr 24, 2020 at 04:22:46PM -0400, Bob kb8tq wrote:
>>
>> Hi
>>
>
> Hello Bob,
On Fri, Apr 24, 2020 at 04:22:46PM -0400, Bob kb8tq wrote:
>
> Hi
>
Hello Bob,
> Assuming you can get a good sky view for the GPS / GNSS device, that’s about
> all you need. Feed it into whatever computer you decide to use and move on.
> The
> OCXO is simply a power hungry “non contributor” in
I use Garmin 18 for this purpose. It's like 80 dollars and it's smaller than a
hockey puck. It includes GPS, antenna, and RS232 like interface. You MUST get
LVD version. USB version and PC version does not have 1 second PPS output.
It's quite sensitive. It's magnetic, so I stuck it on top
Hi
Assuming you can get a good sky view for the GPS / GNSS device, that’s about
all you need. Feed it into whatever computer you decide to use and move on. The
OCXO is simply a power hungry “non contributor” in this case.
Bob
> On Apr 24, 2020, at 2:46 PM, Andreas Kempe wrote:
>
> Hello every
Hello everyone,
I want to build an affordable quality time source for my computer
club. I've been toying with the idea of using an oven controlled
oscillator from Ebay for getting a reasonable (0,5 ppm frequency
stability) 1 PPS signal and a cheap GSP chip with UART for syncing the
time. I was thi
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