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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
 
M

Michael

[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


If antenna icons mean the same as those of an Oregon Scientific unit,
your clock's losing the icon altogether means the clock did not receive
(enough) usable signal.

Here, near the PA/ NY border, my two different Oregon Scientific clocks
have no trouble receiving WWVB. TX is much closer to Boulder so one
would think that WWVB would be stronger than here in NY. However, I
read - from a person who seems to know what he's about when it comes to
electronics - that where he lives (even closer to Boulder than TX) WWVB
reception varies between poor and non-existant.

A $10 "atomic" clock? Cool. I would like to take a look under the hood
of one of those. But I have never seen a Walgreens here in NY State.
:-(
 
P

Patrick Lee Humphrey

[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

I have a wall clock (Atomix) and a watch (Casio) that receive it with no
trouble -- the wall clock is receiving the signal about 23 hours a day, from
the looks of it...
 
S

Steven M (remove wax and invalid to reply)

Je 6 Feb 2005 07:45:02 -0800, [email protected] skribis:
[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.

I'm going to guess that either it's too cheap, or that you're too far
from a PBS television station.

http://www.boulder.nist.gov/timefreq/general/pdf/1877.pdf

Houston's PBS station is KUHF TV, broadcast on channel 8. If you
can't receive that station over the air, maybe you can take the clock
somewhere closer to the broadcast antenna, but I don't know where that
is. You could probably call the station and ask where it is, and
confirm whether they carry the NIST time signal. 713-748-8888

http://www.houstonpbs.org/site/PageServer?pagename=abt_staff_directory



--
Steven M - [email protected] (remove wax and invalid to reply)

"The problem is not that there are problems. The problem is expecting
otherwise and thinking that having problems is a problem."
-- Theodore Rubin
 
K

Kim Sleep

Take a look under the hood, and see if you can tap into the existing
antenna, and add some wire to extend it. Maybe take it apart, scan it, or
photograph it, and someone here can suggest where you can tap into it.
 
M

Michael Black

Steven M " ([email protected]) said:
Je 6 Feb 2005 07:45:02 -0800, [email protected] skribis:
[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.

I'm going to guess that either it's too cheap, or that you're too far
from a PBS television station.

PBS has nothing to do with this.

Those clocks receive a 60KHz signal from Colorado, the low frequency chosen
for good penetration.

And I've never had a problem with my $20 clock from Radio Shack, here
in Montreal, which has to be further away from Colorada than Houston.

Placement can be a factor. I did have to fiddle a bit with where I put it
when I got it a year ago. And there are some places in the house where
I lose the signal, even though the change in location is in yards.

I suspect there is fairly little difference between clocks, with cosmetics
being the big factor. So cost likely means very little.

Local noise can affect reception. Placing it on a tv set likely will mess
up the clock's ability to receive the WWVB signal.

Many tend to only check the WWVB signal once a day, usually in the very
early hours of the morning when reception may be best and local
interfereance minimal. If that's the design, it may not sync up
until enough time has elapsed. Of course, some have a button to press
to sync on demand, which allows multiple attempts as the clock is moved
around.

Michael
 
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
 
D

DaveM

[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

Location and orientation are key considerations to making one of these guys
work well. Be sure to keep the clock well away (>8 ft) from any TVs and
computers. Orient the clock so that the antenna is broadside to the
direction of Boulder, CO from your location. Check the instructions to see
which way the clock should be positioned relative to Boulder. If your clock
is placed inside a building with a lot of metal in the structure (steel wall
studs) or surroundings (metal sidng), that may inhibit good reception.

These clocks normally only try to sync with WWVB around midnite, which is
normally the time the signal strength is highest. You might wait until late
at night and try to sync manually. I live in Fla, and have had no trouble
making several of these clocks work reliably.

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

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

qquito

I bought one for $14.98 three days ago which is designed for setting on
a table as well as hanging on a wall. It was shortly after 2:00 PM EST
(I am in Virginia), and I tried everything you did, indoor and outdoor,
EXCEPT manually adjusting the time which started at 12:00 AM on January
1, and nothing worked.

In the following one hour and a half, it attempted to receive the
signal again (by showing the radio tower icon) but failed.

Then I put it on a desk and left home. When I got home after 2:00 AM,
the clock HAD successfully received the signal. Month, Date and Day of
the Week were all right.

So far, everything appears fine.

Roland
 
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?
 
J

John Miller

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.
 
M

Michael

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").
 
V

Voice of freedom

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?
 
V

Voice of freedom

John Miller said:
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.
 
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...
 
J

Jim Thompson

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
 
D

DaveM

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!!
 
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