Empathy List Archives

R

rcbuck@atcelectronics.com

Wed, Jul 22, 2020 3:51 AM

Paul, thanks for the suggestions. The top of the minute is a good idea.
Since the first second is part of the sync pattern it will always be 0
and the phase would be 0. A differential opamp with one input from WWVB
and the other from the local source fed to the STM32 would tell if the
signals were in phase. A single gate inverter controlled by the STM32
could be used to invert the local source if necessary.

I have worked with the Bluepill for the last year on a few small
projects. The most complex one (which isn't really complex) was to
control two stepper motors. I really like the boards and you can't beat
the prices. I don't use the bootloader so I have no experience with it.

Dana, I looked at the Costas loop and had sort of ruled it out. I may
take another look at it as I get further into the project. I will
probably use a 15.360 MHz oscillator and divide by 256 to get the 60 kHz
local source. Once I get the front end working I will be able to start
some "real" testing.

Suggestions from others are welcome.

Ray,
AB7HE

Paul, thanks for the suggestions. The top of the minute is a good idea. Since the first second is part of the sync pattern it will always be 0 and the phase would be 0. A differential opamp with one input from WWVB and the other from the local source fed to the STM32 would tell if the signals were in phase. A single gate inverter controlled by the STM32 could be used to invert the local source if necessary. I have worked with the Bluepill for the last year on a few small projects. The most complex one (which isn't really complex) was to control two stepper motors. I really like the boards and you can't beat the prices. I don't use the bootloader so I have no experience with it. Dana, I looked at the Costas loop and had sort of ruled it out. I may take another look at it as I get further into the project. I will probably use a 15.360 MHz oscillator and divide by 256 to get the 60 kHz local source. Once I get the front end working I will be able to start some "real" testing. Suggestions from others are welcome. Ray, AB7HE

RA

rodger_adams@yahoo.com

Wed, Jul 22, 2020 2:35 PM

Hey Ray,

Paul and I have a nice piece of code that generates the WWVB BPSK bit stream
using an Arduino and a ublox GPS module. (total cost under $30) You could
use this as a WWVB emulator while you're working on your code. Sorry, I
can't really help with your question about demodulating the WWVB BPSK but
the Costas loop sounds like the way to go. It has also been suggested that
a WWVB SDR wouldn't be too difficult to build and would open up lots of
possibilities. Unfortunately, I don't have a clue where to begin with that.
Maybe somebody with some SDR experience can chime in.

Re your comment about $30 BPSK clocks. The only clock I'm aware of that
uses the BPSK is the Lacrosse Ultratomic. Are you aware of any others?

Thanks,

Rodger

-----Original Message-----
From: time-nuts time-nuts-bounces@lists.febo.com On Behalf Of
rcbuck@atcelectronics.com
Sent: Tuesday, July 21, 2020 11:52 PM
To: Discussion of precise time and frequency measurement
time-nuts@lists.febo.com
Subject: Re: [time-nuts] WWVB PM Time Questions

Paul, thanks for the suggestions. The top of the minute is a good idea.
Since the first second is part of the sync pattern it will always be 0 and
the phase would be 0. A differential opamp with one input from WWVB and the
other from the local source fed to the STM32 would tell if the signals were
in phase. A single gate inverter controlled by the STM32 could be used to
invert the local source if necessary.

I have worked with the Bluepill for the last year on a few small projects.
The most complex one (which isn't really complex) was to control two stepper
motors. I really like the boards and you can't beat the prices. I don't use
the bootloader so I have no experience with it.

Dana, I looked at the Costas loop and had sort of ruled it out. I may take
another look at it as I get further into the project. I will probably use a
15.360 MHz oscillator and divide by 256 to get the 60 kHz local source. Once
I get the front end working I will be able to start some "real" testing.

Suggestions from others are welcome.

Ray,
AB7HE

time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Hey Ray, Paul and I have a nice piece of code that generates the WWVB BPSK bit stream using an Arduino and a ublox GPS module. (total cost under $30) You could use this as a WWVB emulator while you're working on your code. Sorry, I can't really help with your question about demodulating the WWVB BPSK but the Costas loop sounds like the way to go. It has also been suggested that a WWVB SDR wouldn't be too difficult to build and would open up lots of possibilities. Unfortunately, I don't have a clue where to begin with that. Maybe somebody with some SDR experience can chime in. Re your comment about $30 BPSK clocks. The only clock I'm aware of that uses the BPSK is the Lacrosse Ultratomic. Are you aware of any others? Thanks, Rodger -----Original Message----- From: time-nuts <time-nuts-bounces@lists.febo.com> On Behalf Of rcbuck@atcelectronics.com Sent: Tuesday, July 21, 2020 11:52 PM To: Discussion of precise time and frequency measurement <time-nuts@lists.febo.com> Subject: Re: [time-nuts] WWVB PM Time Questions Paul, thanks for the suggestions. The top of the minute is a good idea. Since the first second is part of the sync pattern it will always be 0 and the phase would be 0. A differential opamp with one input from WWVB and the other from the local source fed to the STM32 would tell if the signals were in phase. A single gate inverter controlled by the STM32 could be used to invert the local source if necessary. I have worked with the Bluepill for the last year on a few small projects. The most complex one (which isn't really complex) was to control two stepper motors. I really like the boards and you can't beat the prices. I don't use the bootloader so I have no experience with it. Dana, I looked at the Costas loop and had sort of ruled it out. I may take another look at it as I get further into the project. I will probably use a 15.360 MHz oscillator and divide by 256 to get the 60 kHz local source. Once I get the front end working I will be able to start some "real" testing. Suggestions from others are welcome. Ray, AB7HE _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.

R(

Richard (Rick) Karlquist

Wed, Jul 22, 2020 4:05 PM

On 7/22/2020 7:35 AM, Rodger via time-nuts wrote:

Hey Ray,

Paul and I have a nice piece of code that generates the WWVB BPSK bit stream
using an Arduino and a ublox GPS module. (total cost under $30) You could
use this as a WWVB emulator while you're working on your code. Sorry, I
can't really help with your question about demodulating the WWVB BPSK but
the Costas loop sounds like the way to go.

Rodger

A long time ago, I built a demodulator for some weather satellite
that used BPSK that used a Costas loop driving a VCXO. I had
never built a Costas loop before, but I have to say that it was
quite straightforward and it totally worked as advertised.
The loop requires an analog multiplier, and I didn't have much
trouble sourcing it. Fast forward to today, and the same small
number of multipliers are still available, they just cost a lot.

For 60 kHz, of course, you will want to divide down a VCXO that is
at a reasonable frequency for such.

Rick N6RK

On 7/22/2020 7:35 AM, Rodger via time-nuts wrote: > Hey Ray, > > Paul and I have a nice piece of code that generates the WWVB BPSK bit stream > using an Arduino and a ublox GPS module. (total cost under $30) You could > use this as a WWVB emulator while you're working on your code. Sorry, I > can't really help with your question about demodulating the WWVB BPSK but > the Costas loop sounds like the way to go. > > Rodger > A long time ago, I built a demodulator for some weather satellite that used BPSK that used a Costas loop driving a VCXO. I had never built a Costas loop before, but I have to say that it was quite straightforward and it totally worked as advertised. The loop requires an analog multiplier, and I didn't have much trouble sourcing it. Fast forward to today, and the same small number of multipliers are still available, they just cost a lot. For 60 kHz, of course, you will want to divide down a VCXO that is at a reasonable frequency for such. Rick N6RK

PS

paul swed

Wed, Jul 22, 2020 5:25 PM

The KD2BD receiver is a costas loop.
So look at that and you have the answer. It does not decode the BPSK data
though. Thats quite a project all by itself.
Regards
Paul

On Wed, Jul 22, 2020 at 10:42 AM Rodger via time-nuts <
time-nuts@lists.febo.com> wrote:

Hey Ray,

Paul and I have a nice piece of code that generates the WWVB BPSK bit
stream
using an Arduino and a ublox GPS module. (total cost under $30) You could
use this as a WWVB emulator while you're working on your code. Sorry, I
can't really help with your question about demodulating the WWVB BPSK but
the Costas loop sounds like the way to go. It has also been suggested that
a WWVB SDR wouldn't be too difficult to build and would open up lots of
possibilities. Unfortunately, I don't have a clue where to begin with
that.
Maybe somebody with some SDR experience can chime in.

Re your comment about $30 BPSK clocks. The only clock I'm aware of that
uses the BPSK is the Lacrosse Ultratomic. Are you aware of any others?

Thanks,

Rodger

-----Original Message-----
From: time-nuts time-nuts-bounces@lists.febo.com On Behalf Of
rcbuck@atcelectronics.com
Sent: Tuesday, July 21, 2020 11:52 PM
To: Discussion of precise time and frequency measurement
time-nuts@lists.febo.com
Subject: Re: [time-nuts] WWVB PM Time Questions

Paul, thanks for the suggestions. The top of the minute is a good idea.
Since the first second is part of the sync pattern it will always be 0 and
the phase would be 0. A differential opamp with one input from WWVB and the
other from the local source fed to the STM32 would tell if the signals were
in phase. A single gate inverter controlled by the STM32 could be used to
invert the local source if necessary.

I have worked with the Bluepill for the last year on a few small projects.
The most complex one (which isn't really complex) was to control two
stepper
motors. I really like the boards and you can't beat the prices. I don't use
the bootloader so I have no experience with it.

Dana, I looked at the Costas loop and had sort of ruled it out. I may take
another look at it as I get further into the project. I will probably use a
15.360 MHz oscillator and divide by 256 to get the 60 kHz local source.
Once
I get the front end working I will be able to start some "real" testing.

Suggestions from others are welcome.

Ray,
AB7HE

time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

The KD2BD receiver is a costas loop. So look at that and you have the answer. It does not decode the BPSK data though. Thats quite a project all by itself. Regards Paul On Wed, Jul 22, 2020 at 10:42 AM Rodger via time-nuts < time-nuts@lists.febo.com> wrote: > Hey Ray, > > Paul and I have a nice piece of code that generates the WWVB BPSK bit > stream > using an Arduino and a ublox GPS module. (total cost under $30) You could > use this as a WWVB emulator while you're working on your code. Sorry, I > can't really help with your question about demodulating the WWVB BPSK but > the Costas loop sounds like the way to go. It has also been suggested that > a WWVB SDR wouldn't be too difficult to build and would open up lots of > possibilities. Unfortunately, I don't have a clue where to begin with > that. > Maybe somebody with some SDR experience can chime in. > > Re your comment about $30 BPSK clocks. The only clock I'm aware of that > uses the BPSK is the Lacrosse Ultratomic. Are you aware of any others? > > Thanks, > > Rodger > > -----Original Message----- > From: time-nuts <time-nuts-bounces@lists.febo.com> On Behalf Of > rcbuck@atcelectronics.com > Sent: Tuesday, July 21, 2020 11:52 PM > To: Discussion of precise time and frequency measurement > <time-nuts@lists.febo.com> > Subject: Re: [time-nuts] WWVB PM Time Questions > > Paul, thanks for the suggestions. The top of the minute is a good idea. > Since the first second is part of the sync pattern it will always be 0 and > the phase would be 0. A differential opamp with one input from WWVB and the > other from the local source fed to the STM32 would tell if the signals were > in phase. A single gate inverter controlled by the STM32 could be used to > invert the local source if necessary. > > I have worked with the Bluepill for the last year on a few small projects. > The most complex one (which isn't really complex) was to control two > stepper > motors. I really like the boards and you can't beat the prices. I don't use > the bootloader so I have no experience with it. > > Dana, I looked at the Costas loop and had sort of ruled it out. I may take > another look at it as I get further into the project. I will probably use a > 15.360 MHz oscillator and divide by 256 to get the 60 kHz local source. > Once > I get the front end working I will be able to start some "real" testing. > > Suggestions from others are welcome. > > Ray, > AB7HE > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. >

LV

Lester Veenstra

Wed, Jul 22, 2020 6:14 PM

Software Costas, see MatLab:
https://www.mathworks.com/matlabcentral/fileexchange/16744-demodulating-a-bp
sk-using-costas-loop?s_tid=FX_rc2_behav

Lester B Veenstra K1YCM MØYCM W8YCM 6Y6Y
lester@veenstras.com

452 Stable Ln (HC84 RFD USPS Mail)
Keyser WV 26726

GPS: 39.336826 N 78.982287 W (Google)
GPS: 39.33682 N 78.9823741 W (GPSDO)

Telephones:
Home:                   +1-304-289-6057
US cell                    +1-304-790-9192
Jamaica cell:           +1-876-456-8898

-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@lists.febo.com] On Behalf Of paul
swed
Sent: Wednesday, July 22, 2020 1:26 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] WWVB PM Time Questions

The KD2BD receiver is a costas loop.
So look at that and you have the answer. It does not decode the BPSK data
though. Thats quite a project all by itself.
Regards
Paul

On Wed, Jul 22, 2020 at 10:42 AM Rodger via time-nuts <
time-nuts@lists.febo.com> wrote:

Hey Ray,

Paul and I have a nice piece of code that generates the WWVB BPSK bit
stream
using an Arduino and a ublox GPS module. (total cost under $30) You could
use this as a WWVB emulator while you're working on your code. Sorry, I
can't really help with your question about demodulating the WWVB BPSK but
the Costas loop sounds like the way to go. It has also been suggested

that

a WWVB SDR wouldn't be too difficult to build and would open up lots of
possibilities. Unfortunately, I don't have a clue where to begin with
that.
Maybe somebody with some SDR experience can chime in.

Re your comment about $30 BPSK clocks. The only clock I'm aware of that
uses the BPSK is the Lacrosse Ultratomic. Are you aware of any others?

Thanks,

Rodger

-----Original Message-----
From: time-nuts time-nuts-bounces@lists.febo.com On Behalf Of
rcbuck@atcelectronics.com
Sent: Tuesday, July 21, 2020 11:52 PM
To: Discussion of precise time and frequency measurement
time-nuts@lists.febo.com
Subject: Re: [time-nuts] WWVB PM Time Questions

Paul, thanks for the suggestions. The top of the minute is a good idea.
Since the first second is part of the sync pattern it will always be 0 and
the phase would be 0. A differential opamp with one input from WWVB and

the

other from the local source fed to the STM32 would tell if the signals

were

in phase. A single gate inverter controlled by the STM32 could be used to
invert the local source if necessary.

I have worked with the Bluepill for the last year on a few small projects.
The most complex one (which isn't really complex) was to control two
stepper
motors. I really like the boards and you can't beat the prices. I don't

use

the bootloader so I have no experience with it.

Dana, I looked at the Costas loop and had sort of ruled it out. I may take
another look at it as I get further into the project. I will probably use

a

15.360 MHz oscillator and divide by 256 to get the 60 kHz local source.
Once
I get the front end working I will be able to start some "real" testing.

Suggestions from others are welcome.

Ray,
AB7HE

time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.

Software Costas, see MatLab: https://www.mathworks.com/matlabcentral/fileexchange/16744-demodulating-a-bp sk-using-costas-loop?s_tid=FX_rc2_behav Lester B Veenstra K1YCM MØYCM W8YCM 6Y6Y lester@veenstras.com 452 Stable Ln (HC84 RFD USPS Mail) Keyser WV 26726 GPS: 39.336826 N 78.982287 W (Google) GPS: 39.33682 N 78.9823741 W (GPSDO) Telephones: Home: +1-304-289-6057 US cell +1-304-790-9192 Jamaica cell: +1-876-456-8898 -----Original Message----- From: time-nuts [mailto:time-nuts-bounces@lists.febo.com] On Behalf Of paul swed Sent: Wednesday, July 22, 2020 1:26 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] WWVB PM Time Questions The KD2BD receiver is a costas loop. So look at that and you have the answer. It does not decode the BPSK data though. Thats quite a project all by itself. Regards Paul On Wed, Jul 22, 2020 at 10:42 AM Rodger via time-nuts < time-nuts@lists.febo.com> wrote: > Hey Ray, > > Paul and I have a nice piece of code that generates the WWVB BPSK bit > stream > using an Arduino and a ublox GPS module. (total cost under $30) You could > use this as a WWVB emulator while you're working on your code. Sorry, I > can't really help with your question about demodulating the WWVB BPSK but > the Costas loop sounds like the way to go. It has also been suggested that > a WWVB SDR wouldn't be too difficult to build and would open up lots of > possibilities. Unfortunately, I don't have a clue where to begin with > that. > Maybe somebody with some SDR experience can chime in. > > Re your comment about $30 BPSK clocks. The only clock I'm aware of that > uses the BPSK is the Lacrosse Ultratomic. Are you aware of any others? > > Thanks, > > Rodger > > -----Original Message----- > From: time-nuts <time-nuts-bounces@lists.febo.com> On Behalf Of > rcbuck@atcelectronics.com > Sent: Tuesday, July 21, 2020 11:52 PM > To: Discussion of precise time and frequency measurement > <time-nuts@lists.febo.com> > Subject: Re: [time-nuts] WWVB PM Time Questions > > Paul, thanks for the suggestions. The top of the minute is a good idea. > Since the first second is part of the sync pattern it will always be 0 and > the phase would be 0. A differential opamp with one input from WWVB and the > other from the local source fed to the STM32 would tell if the signals were > in phase. A single gate inverter controlled by the STM32 could be used to > invert the local source if necessary. > > I have worked with the Bluepill for the last year on a few small projects. > The most complex one (which isn't really complex) was to control two > stepper > motors. I really like the boards and you can't beat the prices. I don't use > the bootloader so I have no experience with it. > > Dana, I looked at the Costas loop and had sort of ruled it out. I may take > another look at it as I get further into the project. I will probably use a > 15.360 MHz oscillator and divide by 256 to get the 60 kHz local source. > Once > I get the front end working I will be able to start some "real" testing. > > Suggestions from others are welcome. > > Ray, > AB7HE > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.