Atomic Clock Movements

EST, CST, MST, PST, DST

 

Attention:  NIST station WWV and sister stations are among the oldest radio stations in the United States, having been in continuous operation since May 1920. The station has transmitted the official US Time for nearly 100 years, and is an instrumental part in the telecommunications field, ranging from broadcasting to scientific research and education. Additionally, these stations transmit marine storm warnings from the National Weather Service, GPS satellite health reports, and specific information concerning current solar activity, and radio propagation conditions. These broadcasts are an essential resource to the worldwide communications industry.

However, because of so-called budget restraints, WWVB may stop broadcast the 60 kHz time sync signal.  This will in essence render these atomic clock movements nearly useless. This shutdown will also include WWV broadcasts and WWVH Hawaii time sync signal.

    

This article is about the quartz movement I use in the clocks I build.

I have used many including expensive wined-up chime mechanisms, wooden gear movements, electric and the ubiquitous quartz movement.  After several years of experimentation, I think I found the movement that is best suited for my work.

First of all, the idea of an elegant hand-wound chime mantel clock sounds romantic. But it is my experience that we who have these mechanical marvels, eventually let them run down or we soon turn off the chimes and then after a while we let them run down…and we never wind them again…for years. Then when we do decide to wind them, the mechanism needs to be cleaned and oiled.  Also they are very finicky and without constant attention, they either run fast or slow…depending upon the ever changing summer and winter ambient conditions.

OK, I know…  I'm really not being critical.  I applaud those who faithfully wind and tend to their clocks every 7 days…   But for the rest of us, the cabinet can tell the story of our artistic clock making abilities.  Besides, wind-up clocks were for a more eloquent simpler time.

As for the tacky “quartz” movement…

If we have to stick one of these kitschy things inside our wonderful wood, metal, ceramic, etc. clock case we spent hours if not days making, shouldn’t this electro-mechanical time apparatus work for us?

WWVB Time Sync

As far as I can tell, there are only 4 movements that can be purchased which have WWVB synchronization capabilities. They are Atomix (China), Hechinger (Germany), Takane (China) and U. T. S. (now China).

Note.  My residence and clock shop are in the Northern part of Cincinnati which is in South Western Ohio.   

Ten or so years ago, I purchased a small radio controlled digital alarm clock from Radio Shack as an alternative to my regular clock radio.  I got it home and at about 2 or 3 in the afternoon, I installed the batteries.  Shortly afterwards, it set itself.  The problem was that its tiny beeper was rather obnoxious, so I put it on a shelf and used it merely to set the other clocks in the house by.   The point being is, despite the high tension lines within a half mile of my home, the 60 kHz time sync carrier is receivable and useable any time during the day or night.   

The Movements

Atomix  

  • Reception Synchronize: up to 5 Times per Day
  • Accurate to +/- 1 Second per Day
  • DST Changeover: Automatic, Always Enabled
  • Step Second Hand Motion
  • Smooth Minute Hand Motion
  • Shaft Diameter: 5/16"
  • Dimensions: 3 5/8"H x 2 3/16"W x 5/8"D
  • Sweep Second Hand is Required to Set Clock
  • AA battery
  • Minute hand shaft slotted with screw nut/cap
  • 4 threaded shaft lengths:

Type

Maximum Dial Thickness

Total Hand Shaft Length

High Torque

1/4"

11/16"

Regular

1/4"

11/16"

Regular

3/4"

1 3/16"

Regular

1/2"

15/16"

Regular

1/8"

7/16"

 

Hechinger

  • Reception Synchronize: Once Daily
  • Time Zones: Pacific, Mountain, Central, Eastern
  • DST Changeover: Automatic, can be disabled
  • Step Second Hand Motion
  • Smooth Minute Hand Motion
  • AA Battery
  • Battery Life 1.5-2 years
  • Dimensions: 2.25" wide x 3.5" tall x .75" thick
    (1.25" thick including hand stem.)
  • Hour hand shaft size 3.5mm (.137 inches)
  • Minute hand shaft friction fit size 5mm (.196 inches)
  • Threaded Bushing: None bushing supplied

 

Takane

  • Reception Synchronize: daily
  • Time Zones: Pacific, Mountain, Central, Eastern
  • DST Changeover: Automatic, can be disabled
  • Step Second Hand Motion
  • Step Minute Hand Motion (1/4 minute every 15 seconds)
  • AA battery
  • Dimensions: 3 5/8" H x 2 1/4" W x 11/16" D
  • Minute Hand Shaft friction fit
  • 2 threaded shaft lengths:
Maximum Dial Thickness Threaded Shaft Length Overall Shaft Length
1/8” 3/16" 7/16"
3/8” 7/16" 11/16"

 

U. T. S.

  • Reception Synchronize: daily
  • Time Zones: Pacific, Mountain, Central, Eastern
  • DST Changeover: Automatic, can be disabled
  • Step Second Hand Motion
  • Step Minute Hand Motion (1/4 minute every 15 seconds)
  • Dimension: 2 1/4 W, 3 5/8 H, 11/16 D Shaft Length 3/8”
  • Threaded Bushing: Face Thickness from 1/4" to 7/16" Overall Shaft length 13/16”

 

 

Comparison
  Atomix Hechinger Takane U. T. S.
Number of Shaft Lengths 4 1 2 1
Threaded Shaft yes no yes no
High Torque yes* no no no
Overall Size small medium very large large
Snap-in Footprint yes no no no
Noise silent loud nearly silent noticeable
Alignment Lock Pin no yes no yes
Second Hand Required yes no no no
Sensitivity poor poor** excellent very good
Minute Hand Fit slotted w/nut friction friction friction
Minute Hand Movement smooth smooth 1/4 step 1/4 step
Number of Motors 1 1 2 2
Time Zone Setting none dial dial buttons
Disable DST yes yes yes yes
Ease of Setting*** complicated simplest 2 steps 1 step
Max DST Correction 60 min 45 min 144 seconds 144 seconds
Use With Metal Face no no no no
Cost $13**** $16 $17 $35
Overall Rating ok poor excellent very good

* High torque available in one shaft length only
** sometimes can set to wrong time
*** The number of steps needed by the end user to set the clock after battery replacement
**** High torque is $18

 

Easiest for end user to set after battery replacement:

Hechenger - Just install the battery.  The rotary switch is already set.
U. T. S - Insert the battery and press the appropriate time zone button.
Takane - Insert the battery, then when the second hand reaches the 12, press set button.
Atomix - Complicated.

 

Quiet:

Atomix - no sound,
Takane - a little click at the top of the hour depending upon the face plate,
U. T. S. - audible ticking,
Hechenger - unusually loud ticking.

 

Reliability:

U. T. S - Good,
Takane - Sometimes does not readjust for DST for several days.
Atomix - Can sometimes go out of sync, or not readjust for DST,
Hechenger - Even though it keeps the correct time, can sometimes reset itself.  This diminishes battery life as well as be annoying.

 

Explanations

The first WWVB time-sync capable movement I became enamored with while cruising the web was the German made Hechinger.  The picture on the website was a bit vague, but I really wanted to see if this thing would work for me.   So, to try this movement out, I decided to convert a small bathroom wall clock. 


Bushing nut used on the
Hechinger & UTS

When I received the package, I opened the box and saw that the Hechinger had no threaded shaft.  It has the same type of inside threads as does the UTS.  Because I could not find one of these special nuts, I had to build a three sided rectangle with a dado to hold it down.  I had to consider the battery compartment, and the plastic clock.  I installed the movement, set up the hands and I hung the modified clock back on the wall of the bathroom.  It would not sync.  Finally some time during the night, it set itself to the correct time.  I thought all was well.  Then several days later at about 9:15 pm, the clock decided to set itself again. The problem was that it eventually set itself to the wrong time.  I then read online where other people were having similar problems. 

Also, sleeping fairly close to the bedroom, I could hear this loud clank, clank all night.  I soon got in the habit of closing the bathroom door and eventually learning not to bang into it in the middle of the night.

Standard movement

Atomix

The next movement I bought was the Atomix.  Too bad I didn't try this movement first on the bathroom clock.  It would have just snapped onto the existing footprint of the original quartz movement.  The Atomix is a standard movement with a box attached to the top end.  This is where the antenna is located.

The reason I got this movement was because the antenna looked like it could be detached.   As you may or may not be aware of, these movements do not receive data if they are mounted up against or even near a metal surface.  This is because they use VLF radio waves. 

I detached the antenna, added a piece of wire linking the antenna to the movement.  I could then place the antenna away from the metal face of the clock.


Modified Atomix

The antenna cover was glued together with a tacky type adhesive, so it was fairly easy to pry apart with an Xacto knife.  The tab of the circuit board where the antenna wires were connected stuck out far enough such that I didn't have to take the movement case apart.  I figured out which conductor in the tab was shield ground by using an ohm meter between the negative (-) pole of the battery holder terminal and the antenna connectors on the board.  The one that had the least resistance was the shield ground.  I later realized that I didn't need a coaxial cable.  Just two wires with fairly thick insulated lightly twisted together. 

The idea of changing the tuning characteristics of the antenna by lengthening the leads was not a big deal, especially since I was dealing with a 60kHz wavelength.

Note.  When I bought this movement, I got two of them so I could see if detaching the antenna would make a difference.  After modifying one, I found that both movements performed exactly the same. 

Like the Hechinger, the Atomix also did not start setting itself until late in the evening.  By set I mean, this movement speeds up or slows down to correct itself.  Also, you the end user have to go through several steps to set or reset this clock.  My wife could not do it right.  The next drawback is, this unit requires a second hand for accurate setting.  They say you can count the ticks to set it, but... 

The problems I face were that both Atomix movements did not set themselves very accurately.  Also, one or the other would forget to adjust itself for DST or back again in the fall.

~~~

The next movement I got was the UTS, which was already mounted in a LaCross clock.   I decided to spend $19 and replace the metal faced wall clock I had installed the modified Atomix movement in. 

After taking delivery of the new clock from the UPS guy, I unpacked it and installed a fresh battery. 

I misread the instructions and pressed the tiny DST on/off button by mistake.  The instructions specified for this button to be pressed with a tip of something like a pencil.  After rereading the instructions, I pressed the button again to turn back on the DST.  I must have pressed it too hard, because the rubber button fell through the hole.  Well, I removed the battery and reinstalled it.  This movement defaults to DST-on when you install the battery.  Before I could hang it on the wall, it started to set itself, at 4 in the afternoon.

Even though I missed the old metal clock, I thought I would be happy with the LaCross. 

This clock was in my office, which is at the other end of my bedroom.  This large T shaped room has the office at the bottom end of the tee 27 feet away from the bed. 

The problem with this movement became apparent at night.  There are those who don't mind a ticking sound, but I do.   This clock ended up in the kitchen.  And I replace the Atomix movement in the metal cock with the prior quartz movement. 

This old clock originally had an electrical type movement that received setting and running instructions from a central clock controller.  Since I had no controller and the clock was useless without it, I replaced the old mechanism with a quartz movement.  I really like this big military clock.

~~~

The next and last movement I purchased was the Takane.  This movement has the same characteristics as does the UTS.  The difference is, the Takane is...quiet... 

I got tired of the shenanigans and noise of the Hechinger movement in the bathroom clock, so I replaced it with a Takane.  Unless I put my ear to it, I cannot hear the ticking.

The bathroom clock is an inexpensive Spartus, which is basically a piece of poly styrene plastic.  So, any ticking would be amplified.  Never-the-less, silence.  You-know, this clock is kind-of artsy.  I got it about 20 years ago from the now defunct J. J. Newberry Department Store for $3.

A problem...  The Takane has failed on a number of occasions to set itself to DST and back to ST.  I tried on a number of occasions to figure out why, but...I don't know.

There are still some other noises from the Takane, though.  When the minute hand reaches the hour, there is this tiny click. This tells the microprocessor that the minute hand is at 12:00.  Also, there is an even tinier click when the hour hand gets somewhere around 11:30, telling the tiny computer that the hour hand is nearing 12:00.


U. T. S.

Also, I did not realize this.  The minute hand on UTS (LaCross) clock moves in quarter minute increments instead of moving smoothly hence imperceptibly.  The Takane does the same thing.  This is because both of these movements uses 2 motors instead of the traditional one motor to drive the second hand...which drives the minute hand, which drives the hour hand.  Instead, one motor drives the second hand and the other drives the minute and hour hands.  If you don't want to use a second hand, the second-hand motor is useless.  There doesn't seem to be any way of turning off this motor giving a little extra life to the battery.

Even though the Takane movement has these quirks, I found it to be acceptable.  It is sensitive to the WWVB signal even during the daylight hours, its antenna does not have to be perpendicular to Colorado (the west), and it is quiet & accurate.   

ISI Daylight Savings Movement Motors by Innovation Specialties Inc.


ISI US Daylight Savings Motor sold by ClockParts.com

There is a quartz movement that adjusts itself to daylight savings time on the correct day and time without external radio signals or computer connection such as Bluetooth or Wi-Fi. At two AM in March, the clock movement moves the time one hour forward. At two AM in November, it stops for one hour.

Without any connection to an external reference, how does it do this?

When you remove the movement from its shipping packaging, it has no battery in it. After installing the movement in your project and inserting a battery in it, you have to manually set the time. Then magically at 2 AM when the time change is to occur, the clock movement does its thing.

How does it do that?

 

US @ 2:00 AM

     EU @ 1:00 AM

 

Begins

Ends

Begins

Ends

2017

12-Mar

5-Nov

26-Mar

29-Oct

2018

11-Mar

4-Nov

25-Mar

28-Oct

2019

10-Mar

3-Nov

31-Mar

27-Oct

2020

8-Mar

1-Nov

29-Mar

25-Oct

2021

14-Mar

7-Nov

28-Mar

31-Oct

2022

13-Mar

6-Nov

27-Mar

30-Oct

2023

12-Mar

5-Nov

26-Mar

29-Oct

2024

10-Mar

3-Nov

31-Mar

27-Oct

2025

9-Mar

2-Nov

30-Mar

26-Oct

The manufacturer has added a chip to the movement that stores a calendar in it which is said to be good until 2099.

So? How does it know when or what day it is and what time it is?


Calender data set at factory - kept alive by button cell

The answer lies in a micro controller chip. What they don’t tell you is this chip itself relies on a long life button cell which keeps the current approximate time. When the movement is manufactured, the day and time is preset. When you install the movement and set the time, the movement’s computer determines if the time you set is either AM or PM by its internal clock. Then when DST is to be adjusted for, it uses its half day calendar clock plus the time you set to determine when to make the change for the begin or end of DST depending upon the season (spring or fall).

The accuracy of this movement is like any other quartz movement in that it depends upon how accurate the internal quartz oscillator is.  An atomic movement will adjust its time based upon the 60 KHz WWVB atomic clock signal. This movement however works like any other standard movement except that it has the additional feature of automatically setting the DST time.

Note. If for some reason this movement were to lose its internal clock, there would be no way of correcting it. However, for $10 more, ISI does make another movement that can be corrected.


ISI World Daylight Savings Motor sold by ClockParts.com

If you notice the image on the right.  This movement has a button cell compartment where you can change the tiny battery and reset the day, month and year.  You can also set the time zone of the country. 

Note.  If any of the governments of the world decide to change the dates of the DST, neither the US or World movements would be accurate for setting DST. 

 

Determination

I use the U. T. S in my all steel military clock.  I found that part of the back of the UTS was open and the ferrite rod antenna was easily removed without damaging it.  Even though the ferrite antenna was glued in with hot melt glue, I could get it out.   I did have to make a cover or container for the antenna.  It's a hollowed out piece of 1 1/2" acrylic rod - which you can see above the clock.

Now the old Edwards military school clock is back in sync.  A second UTS movement I bought replaced an Atomix movement in our wedding anniversary clock pictured on the prior page.

~~~

The best movement thus far is the UTS.  It's easy to set and it has been the best in setting and resetting itself for DST.  The only problems are: it is the highest price movement, about twice that of the others; it is shipped from Canada; and it has a mild tick-tick-tick when mounted on a plastic clock face. 

They Now Work for Me, 24-7-365/6

I hope this gives you some insight into these WWVB capable movements.  I also hope everyone starts to use radio controlled movements.  I have.  With the exception of the thermostats, the stove and microwave, every clock in my house sets itself...including the programmable weekday/weekend clock radio. 

~~~

The above four mentioned movements are available at the following merchants:

Atomix - Klockit

Hechinger - Atomic Tine Company

Takane - CLOCKPARTS.COM

U. T. S. - Arek's Murray Clocks

S 2002