magnetic field

Thad Smith · Sep 29, 2004

Michael wrote:

Screaminet News wrote:

Sorry if this is not the proper newsgroup for this question.

I was wondering if anyone here would know why I saw several battery powered
atomic clocks (which you can buy at Brookstones/Sharper Image/Sams Club,
etc) all in one place that had different times?

I always thought they updated themselves at least daily and they would not
be different by more than a second, if that. I forget now, but they were
VERY different. 20 seconds, at least.

Several possibilities for the different times. First, understand that
none of these clocks displays NIST time in real time; they are, at
heart, stand-along clocks, i.e. with their own oscillators. So after a
clock sets itself from NIST, the time it displays - from that point
until it sets itself the next time - is its own internally incremented
time. If the clock cannot set itself again for "a long time", the time
it displays will show drift with respect to NIST.

Some (most?) of these clocks are programmed to set themselves only once
per day, usually at night because NIST propagation is best during
darkness. So in a location of marginal NIST reception a clock could go
for days or weeks without being able to set itself.

Another factor could be that usually reception is poor in metal
buildings, as retailers tend to use, so the clocks are probably not be
receiving the WWV signal. I have one that instructed me, after
inserting batteries, to place it in a window facing Colorado. Since I
like in Boulder County, Colorado, that was an easy one. ;-) Mine
sports hands, with the second hand jumping each second. It's spot on.

Thad

Harry Conover · Sep 29, 2004

"Screaminet News" <tswirsky@screaminet.com> wrote in message news:<bfmcth0126h@enews2.newsguy.com>...

Sorry if this is not the proper newsgroup for this question.

I was wondering if anyone here would know why I saw several battery powered
atomic clocks (which you can buy at Brookstones/Sharper Image/Sams Club,
etc) all in one place that had different times?

I always thought they updated themselves at least daily and they would not
be different by more than a second, if that. I forget now, but they were
VERY different. 20 seconds, at least.

Realixe first that the "Atomic Clocks" sold by Sharper Image are not
atomic clocks at all, they simply are supposed to syncrohize with the
NBS clock at certain times of day. Read the fine print and that
should give you a clue to what they are selling.

If you find a real atomic clock selling for a price under
$4,000 please email me.

Harry C.

Harry C.

Jerry Greenberg · Sep 29, 2004

They call these battery Atomic Clocks, but in fact they are digital
quartz clocks that take their time from the NIST, or one of the number
of other time standard services.

The correct name would be a "Radio Synchronized Clock", and NOT an
Atomic Clock. The average person would never have the funds, and or
resources to purchase and maintain a real atomic clock!

The clock has to be first set up to the proper time zone, and put in
the mode to receive the time exteraly. The instruction manual should
have the details for the particular model.

In a store environment as like in a shopping plaza or department
store, with all the lighting, concrete walls, and etc, the signal that
it must receive must be highly reduced. At home where the receipton of
outside signals are much better, the clock should work normaly. The
instruction manual should give the details of how to properly set it
up.

As a vendor, I would think it is bad sales practice to have the clocks
all being off time to each other. I would have taken the time to set
them properly, and then to have the necessary information about them
posted. But, this is their problem.

The principle of the clock is that it uses a receiver with a decoder
that can decode the time that is sent on the carrier of the NIST
station, or the service being used. There are a number of frequencies
being used, and the receiver has a system that can scan for the best
one.

The reception is effected by the atmospheric probagation factors.
Shortwave listeners and amature radio operators would be familiar with
this. At different times of the day, and under different atmospheric
conditions, radio reception will be affected.

When the clock is receiving the NIST signal it keeps itself
synchronized to the time signal. When the signal dissapears, the clock
will free-run just like any quartz standard clock.

The average accuracy of the clock is dependent on the quality of
design, and the reception of the serviced signal. Most of the
consumer quartz clocks and watches will keep an accuracy of about 5 to
10 seconds per month. This is for a standard free running quartz
clock or watch. There are some very expensive wathes and clocks that
can do a bit better. With a radio synchronized clock, the time
should be more accurate, because of the periodic corrections during
the coarse of each day.

The only error that these clocks will have is their total internal
delay, and the time it takes for the signal to reach, and be processed
in the clock. This is most likely in the micro-second range of error.

The general trend of many of the manufactures is to start making these
clocks the main stream of clocks. This type of clock will be more
common on the market over the next number of years. There are also a
number of watches coming out with this feature. There are some places
where this type of time keeping is now the main stream.

With all of this, I am still late for work at times...

Jerry Greenberg
http://www.zoom-one.com

--

"Screaminet News" <tswirsky@screaminet.com> wrote in message news:<bfmcth0126h@enews2.newsguy.com>...

Sorry if this is not the proper newsgroup for this question.

I was wondering if anyone here would know why I saw several battery powered
atomic clocks (which you can buy at Brookstones/Sharper Image/Sams Club,
etc) all in one place that had different times?

I always thought they updated themselves at least daily and they would not
be different by more than a second, if that. I forget now, but they were
VERY different. 20 seconds, at least.

They can't all be right, so what good are they?

Thanks for any thoughts.

Ted

Jerry Greenberg · Sep 29, 2004

The average error of these clocks is actualy in the microsecond range,
when the signal is being received.

Jerry Greenberg

--

"Ted S." <tswirsky@screaminet.com> wrote in message news:<bfn1ca01u72@enews2.newsguy.com>...

Thanks for all your answers.

Yes, my poor wording. They were synchronized clocks, not atomic clocks. (of
course) I think the person who pointed out the signal might not get through
in a large store had the answer. I think this store was in a large shopping
mall and they were just not receiving their signals. Obvious, but I didn't
think of it.

I'm still assuming that all these type of clocks would be within a second or
so if working properly and getting the signal.

Thanks again.

Ted

Watson A.Name - 'Watt Sun · Sep 29, 2004

In article <460a833b.0307231934.16072115@posting.google.com>,
jerryg50@hotmail.com mentioned...

They call these battery Atomic Clocks, but in fact they are digital
quartz clocks that take their time from the NIST, or one of the number
of other time standard services.

The correct name would be a "Radio Synchronized Clock", and NOT an
Atomic Clock. The average person would never have the funds, and or
resources to purchase and maintain a real atomic clock!

The clock has to be first set up to the proper time zone, and put in
the mode to receive the time exteraly. The instruction manual should
have the details for the particular model.

In a store environment as like in a shopping plaza or department
store, with all the lighting, concrete walls, and etc, the signal that
it must receive must be highly reduced. At home where the receipton of
outside signals are much better, the clock should work normaly. The
instruction manual should give the details of how to properly set it
up.

As a vendor, I would think it is bad sales practice to have the clocks
all being off time to each other. I would have taken the time to set
them properly, and then to have the necessary information about them
posted. But, this is their problem.

Reminds me of Radio Scrap. I go by their TVs as I walk into the
store. Seems like they always have a snowy or otherwise poor quality
picture on them.

The principle of the clock is that it uses a receiver with a decoder
that can decode the time that is sent on the carrier of the NIST
station, or the service being used. There are a number of frequencies
being used, and the receiver has a system that can scan for the best
one.

All the ones I've seen so far use only the signal from WWVB at 60 kHz.

The reception is effected by the atmospheric probagation factors.

[snip]

Jerry Greenberg
http://www.zoom-one.com

--

"Screaminet News" <tswirsky@screaminet.com> wrote in message news:<bfmcth0126h@enews2.newsguy.com>...
Sorry if this is not the proper newsgroup for this question.

I was wondering if anyone here would know why I saw several battery powered
atomic clocks (which you can buy at Brookstones/Sharper Image/Sams Club,
etc) all in one place that had different times?

I always thought they updated themselves at least daily and they would not
be different by more than a second, if that. I forget now, but they were
VERY different. 20 seconds, at least.

They can't all be right, so what good are they?

Thanks for any thoughts.

Ted

--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@

Jim Thompson · Sep 29, 2004

On Wed, 23 Jul 2003 18:08:09 -0400, "Ted S." <tswirsky@screaminet.com>
wrote:

Thanks for all your answers.

Yes, my poor wording. They were synchronized clocks, not atomic clocks. (of
course) I think the person who pointed out the signal might not get through
in a large store had the answer. I think this store was in a large shopping
mall and they were just not receiving their signals. Obvious, but I didn't
think of it.

I'm still assuming that all these type of clocks would be within a second or
so if working properly and getting the signal.

Thanks again.

Ted

It *could* also be how they do their synchronization. IIRC it takes
20 seconds after the minute before all the code is sent (it's 1 baud

480)460-2350 | |
| Jim-T@analog_innovations.com Fax

Jim Thompson · Sep 29, 2004

On Thu, 24 Jul 2003 19:22:23 GMT, "Patch" <bob_acord@hotmail.com>
wrote:

"Andreas Nilsson" <annil@telia.com> wrote in message
news:H8WTa.17555$mU6.15841@newsb.telia.net...
Hello,

I want to record a telephone call, and also have the possibility to feed
the telephone from an own audio source through a connector, rather than
just speaking into the handset.

So, what I need is an adapter with a telephone handset connector in one
end, and two audio connectors (3,5 mm or whatever) in the other end -
one out (that I can connect to a recording device) and one in (that I
can feed with my audio signal).

I have seen a lot of adapters connecting to the telephone handset
connector giving an audio-out connector; but I need something where I
can also provide the signal that is sent to the phone (and to the person
I am talking to).

Thanks in advance.

First, make sure it's legal in your state.

It's legal in Arizona to record calls as long as you are one of the
parties. No "beep" required. Used it to nail an asshole attorney
from Texass ;-) And it was accepted as legitimate evidence in Federal
Court.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice

480)460-2350 | |
| Jim-T@analog_innovations.com Fax

Andreas Nilsson · Sep 29, 2004

Patch wrote:

"Andreas Nilsson" <annil@telia.com> wrote in message
news:H8WTa.17555$mU6.15841@newsb.telia.net...

Hello,

I want to record a telephone call, and also have the possibility to feed
the telephone from an own audio source through a connector, rather than
just speaking into the handset.

So, what I need is an adapter with a telephone handset connector in one
end, and two audio connectors (3,5 mm or whatever) in the other end -
one out (that I can connect to a recording device) and one in (that I
can feed with my audio signal).

I have seen a lot of adapters connecting to the telephone handset
connector giving an audio-out connector; but I need something where I
can also provide the signal that is sent to the phone (and to the person
I am talking to).

Thanks in advance.

First, make sure it's legal in your state.

I live in Sweden. And yes, it is legal here.

Charles Jean · Sep 29, 2004

On Wed, 23 Jul 2003 18:04:45 GMT, Michael <NoSpam@this.addy> wrote:

Screaminet News wrote:

Sorry if this is not the proper newsgroup for this question.

I was wondering if anyone here would know why I saw several battery powered
atomic clocks (which you can buy at Brookstones/Sharper Image/Sams Club,
etc) all in one place that had different times?

I always thought they updated themselves at least daily and they would not
be different by more than a second, if that. I forget now, but they were
VERY different. 20 seconds, at least.

They can't all be right, so what good are they?

Thanks for any thoughts.

Ted

Several possibilities for the different times. First, understand that
none of these clocks displays NIST time in real time; they are, at
heart, stand-along clocks, i.e. with their own oscillators. So after a
clock sets itself from NIST, the time it displays - from that point
until it sets itself the next time - is its own internally incremented
time. If the clock cannot set itself again for "a long time", the time
it displays will show drift with respect to NIST.

Some (most?) of these clocks are programmed to set themselves only once
per day, usually at night because NIST propagation is best during
darkness. So in a location of marginal NIST reception a clock could go
for days or weeks without being able to set itself.

Every clock, even clocks of the same model, are at least sightly
different from one another. Their oscillators - their heartbeat - run
at slightly different rates, and each one drifts at its own rate.

Add all of this up and you should see that what you observe is perfectly
understandable.

What is such a clock good for? If its oscillator is pretty stable and
accurate and if its receiver picks up NIST often, it's good as a clock
that doesn't need human intervention for the "spring ahead; fall back"
foolishness. I have three commercially available WWVB "radio clocks"
(two different models) and have designed and built two WWV clocks. I
love 'em all.
(By the way, I live in New York, USA, and both WWV and WWVB come in just
fine here.)

I built a digital clock around the Dalis 32KHZ TXO chip, and it has a
drift of about 28 seconds/year vs WWV. I would love to hook it up to
WWV and turn into an "atomic clock" set for either WWV or WWVB. Any
way to "twist your arm" to get a post of the schematic of yours?
Charlie

Squawk! Pieces of eight!
Squawk! Pieces of eight!
Squawk! Pieces of eight!
Squawk! Pieces of eight!
Squawk! Pieces of eight!
Squawk! Pieces of nine!
SYSTEM HALTED: parroty error!

Richard Crowley · Sep 29, 2004

"Andreas Nilsson" wrote ...

I want to record a telephone call, and also have the
possibility to feed the telephone from an own audio
source through a connector, rather than just speaking
into the handset.

This is called a "phone patch". Commonly used by radio
amateurs ("hams") Circuits almost certainly posted around
the WWW, and kits and commercial units also available,
depending on your specific situation.

Richard Crowley · Sep 29, 2004

"Andreas Nilsson" wrote ...

Those "commercial units"; do you know of any specific
product, or where to find them? I searched for "telephone
patch", but unfortunately there are a lot of other things that
are called that too.

Ask in one of the news:rec.radio.amateur newsgroups.
Particularly news:rec.radio.amateur.equipment

Zak · Sep 29, 2004

Andreas Nilsson wrote:

I want to record a telephone call, and also have the
possibility to feed the telephone from an own audio
source through a connector, rather than just speaking
into the handset.

Those "commercial units"; do you know of any specific product, or where
to find them? I searched for "telephone patch", but unfortunately there
are a lot of other things that are called that too.

Old Ericsson phones (I thing the T65 qualifies) have a transformer that
is more or less connected to the line, and that can be used to provide
galvanic separation.

It involves some modification of the phone I think.

Thomas

the Wiz · Sep 29, 2004

MFJ sells one for $130US
http://www.mfjenterprises.com/products.php?prodid=MFJ-624D

Andreas Nilsson <annil@telia.com> wrote:

Richard Crowley wrote:

"Andreas Nilsson" wrote ...

I want to record a telephone call, and also have the
possibility to feed the telephone from an own audio
source through a connector, rather than just speaking
into the handset.

This is called a "phone patch". Commonly used by radio
amateurs ("hams") Circuits almost certainly posted around
the WWW, and kits and commercial units also available,
depending on your specific situation.

I've seen some circuits posted, but I haven't the electronic skills to
build something like that on my own.

Those "commercial units"; do you know of any specific product, or where
to find them? I searched for "telephone patch", but unfortunately there
are a lot of other things that are called that too.

More about me: http://thelabwiz.home.mindspring.com/
VB3 source code: http://thelabwiz.home.mindspring.com/vbsource.html
VB6 source code: http://thelabwiz.home.mindspring.com/vb6source.html
VB6 - MySQL how to: http://thelabwiz.home.mindspring.com/mysql.html
My newest language - NSBasic for the Palm PDA: http://thelabwiz.home.mindspring.com/nsbsource.html
Drivers for Pablo graphics tablet and JamCam cameras: http://home.earthlink.net/~mwbt/
johnecarter atat mindspring dotdot com. Fix the obvious to reply by email.

nospam · Sep 29, 2004

dbowey@aol.com (Dbowey) wrote:

Kieth posted, in part:
I know that tens of thousands of potential operators are turned off by the
silly morse code requirement.

I'd like to see the result of your research. I believe you are FOS.

Silly Morse code requirement? Are you so simple minded you can't handle 5 wpm?
I also believe you are an ass.

have a nice day. I'm sure we won't encounter you on the bands.

In this age of the internet and mobile phone amateur radio is dying anyway,
the last thing it needs is artificial barriers to entry.

That said I agree learning morse is probably less of a barrier than having
to communicate with twats like you when you do get on 'the bands'.

Harry Conover · Sep 29, 2004

Jim Thompson <Jim-T@analog_innovations.com> wrote in message news:<dgq2iv45odhheg1rm9hnrvekrhgkt5m1sn@4ax.com>...

On Thu, 24 Jul 2003 22:15:33 -0700, Keith
kilowattradio_spam@earthlink.net> wrote:

Dear Potential Ham Radio Enthusiast,
Recently the international body that regulates the radio spectrum removed the
requirement for knowing morse code to get a 1.8-30 MHz amateur radio license.
If you are interested in ham radio then I urge you to contact the FCC
commissioners and tell them to change the morse code requirement.
[snip]

Please take a few minutes to write a thoughtful note to the FCC Commissioners
to change and improve ham radio. Let us make ham radio useful for teenagers and
adults today.

That's what the CB band is for... the masses, or was that "asses" ?

...Jim Thompson

Thanks for posting that comment Jim. I'm pretty sure that a vast
majority of Hams will agree with you on this, even in the dumbed-down
era that we live in today!

If all the OP want to do is communicate by voice without all the
licensing challenges to satsify, why doesn't he simply use one of
those portable, license-free transcievers known as a Cell Phone?

I was initially licensed at age 12 (which in itself reveals that
neither the code or technical exam tests were that difficult), but
lost my interest during the 1970's when most Hams were using
'store-bought' rather than 'home-brew' rigs. Since most of the QSO
content up to that time involved discussions of what we weere ising
for rigs, and the aspects of their construction and performance, the
conversation content suddently became very limited in technical
content -- a bit like this newsgroup. No more "California Kilowatt"
discussions, with guys proudly boasting about their (largely illegal
rigs) with guy bragging about the pair of Eimac 3X2500F3s that they
were using in their final modulated by a pair of 4-1000s; on the other
end of the spectrum no one describing how they had WAS using only the
3-Watt output 3-W CW rig with a 6V6 as the final. Most Hams at that
time knew that 10-Meters opened up for a brief DX window at roughly
11-year cycles, and would gladly wait for 10-years to exploit its
magic when it did. At that time, antennas still ruled, and most of the
Hams that I knew personally developed a great deal of expertise in the
constructing and tuning of beam antennas, and the big debate was not
the licensing code requirement, but the height limitation placed on
ham radio towers, and whether of not a community had any authority to
regulate them!

I miss those days, and the often greast QSOs that accompanied them.
They don't exist any more, which is why I finally let my license lapse
and concentrated my efforts on off-shore sailing and pyrotechnics!
After all, when a guy tells you that he is using a Kenwood
transciever, how do you come back to that? For me, it's like in 1958
when a guy came back to you using a 'Gooney Box' (Jim, I'm pretty sure
you know what a Gooney Box is/was, but on the Ham bands today, or in
this newsgroup, I'd be willing to bet at least 90% of the people
don't!

Harry C.
(former K2JEZ)

Michael · Sep 29, 2004

Jim Thompson wrote:

On Wed, 23 Jul 2003 18:08:09 -0400, "Ted S." <tswirsky@screaminet.com
wrote:

Thanks for all your answers.

Yes, my poor wording. They were synchronized clocks, not atomic clocks. (of
course) I think the person who pointed out the signal might not get through
in a large store had the answer. I think this store was in a large shopping
mall and they were just not receiving their signals. Obvious, but I didn't
think of it.

I'm still assuming that all these type of clocks would be within a second or
so if working properly and getting the signal.

Thanks again.

Ted

It *could* also be how they do their synchronization. IIRC it takes
20 seconds after the minute before all the code is sent (it's 1 baud
.

A cheap clock might sync at that point, a good clock might wait 40
seconds, add 1 minute and then sync.

...Jim Thompson
--

For WWVB, 18 seconds after the minute, Jim.

26 seconds for
WWV/WWVH.
I designed my WWV clocks not to set until they have decoded three
consecutive minutes successfully. It appears that the commercial WWVB
clocks I have also decode for several minutes before setting; the best
always needs at least 3 minutes after power is applied before it sets
itself.

Michael · Sep 29, 2004

Jerry Greenberg wrote:
[snip]

The principle of the clock is that it uses a receiver with a decoder
that can decode the time that is sent on the carrier of the NIST
station, or the service being used. There are a number of frequencies
being used, and the receiver has a system that can scan for the best
one.

Most (all?) radio synched clocks for the U.S. consumer market receive
only WWVB, and that station broadcasts only on 60 KHz. Battery operated
WWVB clocks typically don't monitor NIST continuously (to conserve
battery) but only once or twice per day, so it is important for accuracy
that their oscillators don't drift terribly.

WWV is the NIST station that transmits on multiple frequencies, and the
last clock I saw that received it on multiple freqs. was the Heathkit
Most Accurate Clock.

With all of this, I am still late for work at times...

Jerry Greenberg
http://www.zoom-one.com

Fred Abse · Sep 29, 2004

On Thu, 24 Jul 2003 04:34:44 +0100, Jerry Greenberg wrote:

The reception is effected by the atmospheric probagation factors.
Shortwave listeners and amature radio operators would be familiar with
this. At different times of the day, and under different atmospheric
conditions, radio reception will be affected.

Not much. They use VLF (60KHz), which is ground wave propagation.
According to coverage maps (NIST web site), apart from perhaps the Pacific
Northwest, part of the day, the whole lower 48 should have greater than
100mV/M all the time. there won't be any fading, 'cos it's ground wave,
and there won't be any of the ionospheric phase distortion that ruins HF
standard frequency transmissions a lot of the time.

--
Then there's duct tape ...
(Garrison Keillor)
nofr@sbhevre.pbzchyvax.pb.hx

Fred Abse · Sep 29, 2004

On Thu, 24 Jul 2003 06:25:04 +0100, Watson A.Name - 'Watt Sun' wrote:

It says "atomic" right on the face of the clock.

That's the luminous hands

--
Then there's duct tape ...
(Garrison Keillor)
nofr@sbhevre.pbzchyvax.pb.hx

Fred Abse · Sep 29, 2004

On Sat, 26 Jul 2003 19:22:51 +0100, Fred Abse wrote:

100mV/M

s/mV/uV

That's microvolts per meter, sorry.

--
Then there's duct tape ...
(Garrison Keillor)
nofr@sbhevre.pbzchyvax.pb.hx

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