Can atomic clock in Houston receive NIST signal?

[cross-posted to sci.electronics.misc, houston.general]

I bought a Ravinia atomic travel alarm clock from Wallgreen. It's small
and has built-in antenna. I set timezone and pressed the button to
manually synchronize. It showed flashing tower icon for about a minute
(searching for signals). Then it showed flashing wave tower icon
(receiving signal) and just tower icon alternately. A few minutes
later, I expected to see stable wave tower icon (synchronized). Instead
I see no icon at all. I tried this outdoors and indoors holding in hand
turning in different directions. I let it sit overnight (indoors).
There's no change. Is this because the built-in antenna is too weak,
Houston is too far from Colorado where NIST real atomic clock is, the
unit is too cheap (<$10)? Thanks for suggestions.

Yong Huang
yong321ATyahoo.com

 

[effi]

yes

 

[Fred Abse]

On Sun, 06 Feb 2005 07:45:02 -0800, yong321 wrote:

Is this because the built-in antenna is too weak, Houston is too far from
Colorado where NIST real atomic clock is,

According to the NIST web site, apart from the Pacific Northwest, and
the Florida peninsula, at certain times of day, WWVB is above 100
microvolts per meter in all the lower 48.

TX is well covered.

http://www.boulder.nist.gov/timefreq/stations/wwvbcoverage.htm

--
Then there's duct tape ...
(Garrison Keillor)

 

Thanks to everybody. It's embarrassing to say but I have to admit that
I was not patient enough when I posted the original message this
morning (around 10 Central Time). I just came back home. Now it's
5:40pm. This clock shows stable wave tower icon! And the time is
slightly slower than most clocks at home so I adjust all other clocks
based on this one.

Yes, it is < $10. In fact, it's labeled $9.99 but they charged me $7.99
plus tax for some reason. I put it on my computer desk all day today
but kept laptop in standby mode, a few inches away. The clock faced
east. But I guess none of these matters. Patience does.

Thanks again.

Yong Huang

 

[Zinc Toast]

"effi" <effi@ev1.net> wrote in message
news:110cgv41l2bee75@corp.supernews.com...

yes

The clock is too cheap, defective and being dumped on the market at a low
price.

 

[Doug McLaren]

In article <1107704702.420659.134720@g14g2000cwa.googlegroups.com>,
<yong321@yahoo.com> wrote:

| Is this because the built-in antenna is too weak,
| Houston is too far from Colorado where NIST real atomic clock is, the
| unit is too cheap (<$10)? Thanks for suggestions.

I live in Austin. I've got a few of these clocks, and I paid even
less than you did. All work fine. Given the right time of day, they
often even work as far away as Alaska, South America or maybe even
Africa. (As long as there's an hour where they can pick up the signal
each day, you're good.)

Also, they're not atomic clocks. They're radio controlled clocks.
As another person suggested, they use the 60 hz signal from WWVB in
Colorado.

More on them here --

http://www.boulder.nist.gov/timefreq/stations/radioclocks.htm

--
Doug McLaren, dougmc@frenzy.com
"I believe we are on an irreversible trend toward more freedom and
democracy - but that could change." --Quayle

 

[effi]

"Zinc Toast" <invalid@invalid.com> wrote in message
news:36nrciF53qqlsU1@individual.net...

"effi" <effi@ev1.net> wrote in message
news:110cgv41l2bee75@corp.supernews.com...
yes


The clock is too cheap, defective and being dumped on the market at a low
price.

you obviously haven't read his subsequent post

your response is cheap, defective, and was dumped on this newsgroup

 

I dished out 50 bucks for a radio controlled (projection) clock from
"The Sharper Image" and I have to say I'm kind of disappointed. I
waited for over an hour during initial setup and tried moving it to a
thousand different locations and different orientations and the closest
I could get to receiving a signal was a blinking tower for no longer
than 2 minutes. I've even turned of my LCD monitor, wireless phones,
bluetooth transmitter and still it does not receive the signal. I've
given in and have set it manually but the unit is still supposed to
check every night at 12 and I will wait and see if it will actually
synchronize (ever).

 

I just realized that ever since I purchased my clock the weather has
been nothing but cloudy skies. Could that be the cause of the poor, if
any, reception?

 

[John Miller]

zeytuntsyan@gmail.com wrote:

I just realized that ever since I purchased my clock the weather has
been nothing but cloudy skies. Could that be the cause of the poor, if
any, reception?

Can't rule it out, but if you were doing the initial setup during
daylight hours, you shouldn't be surprised at no reception. While WWVB
can be received during the day, it's really more of a nighttime band.

--
John Miller, N4VU
email domain: n4vu.com; username: jsm(@)

 

[Michael]

zeytuntsyan@gmail.com wrote:

I dished out 50 bucks for a radio controlled (projection) clock from
"The Sharper Image" and I have to say I'm kind of disappointed. I
waited for over an hour during initial setup and tried moving it to a
thousand different locations and different orientations and the closest
I could get to receiving a signal was a blinking tower for no longer
than 2 minutes. I've even turned of my LCD monitor, wireless phones,
bluetooth transmitter and still it does not receive the signal. I've
given in and have set it manually but the unit is still supposed to
check every night at 12 and I will wait and see if it will actually
synchronize (ever).

Be patient. Very often WWVB comes in like gangbusters here in New York State
during the day, but WWVB usually comes in best at night no matter where you
are. I would not be surprised if your clock has set itself by now.

Neato, those projection clocks! I picked one of those off the shelf at a
regional chain store about 10 years ago. Drooled drooled over it for a moment
before sighing and putting it back. The store was too bright to see the
projected image, even at less than 12", so I decided not to risk disappointment
(closeout; "all sales final").

 

[Voice of freedom]

zeytuntsyan@gmail.com wrote :

I dished out 50 bucks for a radio controlled (projection) clock from
"The Sharper Image" and I have to say I'm kind of disappointed. I
waited for over an hour during initial setup and tried moving it to a
thousand different locations and different orientations and the closest
I could get to receiving a signal was a blinking tower for no longer
than 2 minutes. I've even turned of my LCD monitor, wireless phones,
bluetooth transmitter and still it does not receive the signal. I've
given in and have set it manually but the unit is still supposed to
check every night at 12 and I will wait and see if it will actually
synchronize (ever).

I've had all kinds of problems with mine too, and I live in Denver, fer
pete's sake!

One of mine is an Atomix and it synchs most of the time, but then all of a
sudden it's way off. I contacted the mfg about it and was totally ignored,
they never answered me.

I just bought a different brand that takes an AC adapter and tried running
it off that, but it wouldn't synch at all, then I put batteries in it and
it received full signal strength and would, so I plugged the adapter back
in and it's been fine, it just HAS to have batteries in it for some reason.
It had low signal strength ( it reads a scale of 0-5 ) without the
batteries and is ok with them, with a 4-5 strength. Go figure.

But the Atomix one wont use an adapter, only batteries and it's flaky, even
here in Denver, we're like 60 miles from the 60khz transmitter!

It may have something to do with the antenna? Does anyone know? Would a
ground wire help, or just a wire hanging off the battery clips in the case?

--
A Voice Of Freedom in the
United States of America

 

[Voice of freedom]

John Miller <me2@privacy.net> wrote :

zeytuntsyan@gmail.com wrote:
I just realized that ever since I purchased my clock the weather has
been nothing but cloudy skies. Could that be the cause of the poor, if
any, reception?

Can't rule it out, but if you were doing the initial setup during
daylight hours, you shouldn't be surprised at no reception. While WWVB
can be received during the day, it's really more of a nighttime band.

Isn't it 60khz though? These clocks don't work off the 10-15-20 MHz bands,
do they? I thought they used a loop antenna inside.

--
A Voice Of Freedom in the
United States of America

 

Unit still has not be able to successfully synchronize, but Los Angeles
hasn't seen the sky or sun in quite a while so I'm not surprised.
Knowing that the WWVB bounces their signal off the ionosphere (which I
read is above the clouds) it makes sense for this lack of reception.

I'll wait it out and see...

 

[Jim Thompson]

On Fri, 04 Mar 2005 17:00:44 -0600, Voice of freedom
<VoiceFreedom@freedom.naa> wrote:

John Miller <me2@privacy.net> wrote :

zeytuntsyan@gmail.com wrote:
I just realized that ever since I purchased my clock the weather has
been nothing but cloudy skies. Could that be the cause of the poor, if
any, reception?

Can't rule it out, but if you were doing the initial setup during
daylight hours, you shouldn't be surprised at no reception. While WWVB
can be received during the day, it's really more of a nighttime band.


Isn't it 60khz though? These clocks don't work off the 10-15-20 MHz bands,
do they? I thought they used a loop antenna inside.

It's been just shy of 31 years since I designed one of these... IIRC
the electrical component of the radiation is useless due to man-made
noise at 60KHz.

So you use an electrically-shielded loop antenna.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

 

[DaveM]

<zeytuntsyan@gmail.com> wrote in message
news:1109977317.119406.97710@f14g2000cwb.googlegroups.com...

Unit still has not be able to successfully synchronize, but Los Angeles
hasn't seen the sky or sun in quite a while so I'm not surprised.
Knowing that the WWVB bounces their signal off the ionosphere (which I
read is above the clouds) it makes sense for this lack of reception.

I'll wait it out and see...

WWVB at 60Khz is a ground wave over the coverage area. That's why a VLF
frequency was chosen for the broadcast. Typically, frequencies below 1 MHz
are not reflected by the ionosphere. Propagation is best at night because
the D-Layer of the ionosphere is heavily ionized during daytime hours by the
sun, and causes heavy absorption of the radio energy. Since the sun's
effects are minimal at nighttime, the broadcast signal is least absorbed,
increasing signal strength over the area of coverage.

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in
the address)

Never take a laxative and a sleeping pill at the same time!!

 

[John Miller]

Voice of freedom wrote:

Isn't it 60khz though? These clocks don't work off the 10-15-20 MHz bands,
do they? I thought they used a loop antenna inside.

Yes, that's right.

--
John Miller, N4VU
email domain: n4vu.com; username: jsm(@)
Surplus (For sale or trade):
Tektronix 465B oscilloscope

 

DaveM wrote:

WWVB at 60Khz is a ground wave over the coverage area. That's why a
VLF
frequency was chosen for the broadcast. Typically, frequencies below
1 MHz
are not reflected by the ionosphere. Propagation is best at night
because
the D-Layer of the ionosphere is heavily ionized during daytime hours
by the
sun, and causes heavy absorption of the radio energy. Since the
sun's
effects are minimal at nighttime, the broadcast signal is least
absorbed,
increasing signal strength over the area of coverage.

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate
characters in
the address)

Never take a laxative and a sleeping pill at the same time!!

I am not really aware of the technical details but I did read that "The
LF signal propagates by groundwave, following the curvature of the
earth; the HF signal propagates by skywave, and bounces off the
ionosphere. All signals travel at the speed of light." from
http://www.boulder.nist.gov/timefreq/stations/overview.html

Which I must honestly say confuses me even more...How come there is
mention of two signals? Does that mean the information is simulcasted?

(This clock has taken up more of my time than I'd have expected...)

 

[James T. White]

<zeytuntsyan@gmail.com> wrote in message
news:1109913259.460486.90490@f14g2000cwb.googlegroups.com...

I dished out 50 bucks for a radio controlled (projection) clock from
"The Sharper Image" and I have to say I'm kind of disappointed. I
waited for over an hour during initial setup and tried moving it to a
thousand different locations and different orientations and the closest
I could get to receiving a signal was a blinking tower for no longer
than 2 minutes. I've even turned of my LCD monitor, wireless phones,
bluetooth transmitter and still it does not receive the signal. I've
given in and have set it manually but the unit is still supposed to
check every night at 12 and I will wait and see if it will actually
synchronize (ever).

I live in Houston and bought one of the cheap "Atomic Clocks" at the drugstore.

It took several days but it did finally sync. It seems to do better when placed
by a window. Turning off your cell phone and bluetooth equipment shouldn't be
necessary since they operate at much higher frequencies than the 60 KHz NIST
signal unless they are right next to each other. The biggest sources of
interference for the NIST signals is likely to be the power supplies in your
computer and TV so locate the clock as far away from them as possible.

The sync normally takes place in the wee hours of the morning when the radio
propagation characteristics of the atmosphere are more favorable so be patient.

Good luck.

--
James T. White

 

[Voice of freedom]

zeytuntsyan@gmail.com wrote :

DaveM wrote:
WWVB at 60Khz is a ground wave over the coverage area. That's why a
VLF
frequency was chosen for the broadcast. Typically, frequencies below
1 MHz
are not reflected by the ionosphere. Propagation is best at night
because
the D-Layer of the ionosphere is heavily ionized during daytime hours
by the
sun, and causes heavy absorption of the radio energy. Since the
sun's
effects are minimal at nighttime, the broadcast signal is least
absorbed,
increasing signal strength over the area of coverage.

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate
characters in
the address)

Never take a laxative and a sleeping pill at the same time!!

I am not really aware of the technical details but I did read that "The
LF signal propagates by groundwave, following the curvature of the
earth; the HF signal propagates by skywave, and bounces off the
ionosphere. All signals travel at the speed of light." from
http://www.boulder.nist.gov/timefreq/stations/overview.html

Which I must honestly say confuses me even more...How come there is
mention of two signals? Does that mean the information is simulcasted?

Well sorta but not to the same receivers. The shortwave crowd still uses
the HF band transmissions to calibrate their receivers, I suppose.

--
A Voice Of Freedom in the
United States of America