Clocks, Watches/Musical Wall clock


QUESTION: John,..Thanks for taking my question.   I have a Rhythm musical wall clock,..which I believe is a Timecracker 4MH751 or 752.  the original owner did not take good care of the clock and the batteries corroded and ruined the wiring.   I call the mfg. and they were no help other that to suggest sending it back to them.  All I wanted was the diagram of how the two "D-Cell" batteries are to be connected.  The clock has holders for 3 different batteries.  An AA cell for the movement of the hands.  Another "AA" cell for turning of the hanging Crystal.  A large battery holder for the 2-D Cells.   The mfg. told me that the other two "AA" holders were never used and that all the power is tapped from the mail two "D" cells.   Since most of the wiring has broken off I would appreciate any help you could provide on how to connect the wiring.   It is clear the mail logic board has two wires that connect to 3.0 volts of the 2 "D" cells.  It is not clear how to connect the other two battery cases with 1.5 volts.   Hope you can help.

ANSWER: Bud, I apologize, but I answered your question in some detail and send it.  I just received a notice that it has NOT been sent.  

In brief, many of the companies that sell these battery powered clock companies do not provide parts of diagnostics for them.  It seems that Seiko/Rhythm is one of these.  I have two in my shop right now and the parts and circuitry are quite different.  The only way I could restore one of these types of clocks is to have it in my shop and check out the wiring from the batteries to the switches, motors, etc.

I'm sorry that I cannot help you.

John Newman
Located in Old Prattvillage
Prattville, Alabama

---------- FOLLOW-UP ----------

QUESTION: John,...Being a retired Electronics Engineer I went ahead and tested the minimal wiring that was left and then started re-wiring what was missing.  The way the back cover is placed on the unit it is clear that there is only one access port to the 2 "D" cell batteries and therefore there would never be anyway to replace the other two "AA" batteries without take the entire clock apart, it was obvious that I had to rewire the battery for the turning crystal and the motor for the clock hands, well install an all new battery compartment.  The final task was getting everything to line up such that the new battery case has full access from the rear.   It is now all on the wall and working as designed.   

However, I would really appreciate any basic instruction you can provide on how to maintain the unit.   For example,..I need to know when, where and how to lube or oil the clock mechanism.   I would also like to know how to make tiny changes in the clock when it runs slow.  Is the clock mechanism dependant on the 1.5 volts for accuracy or will it continue to operate for a year as the battery begins to run down.  

Finally, do you know if there is anyplace where I can purchase a new logic card that contains chips that have more than 6 songs.  I have seen some that play up to 30 songs.

The clock is really made up of 3 separate sub systems,...1.  The time movement.  2.  the Spinning Crystal.   3.  The musical clock movement.  the only real inter-connection is when the clock hands touch the hour.  I have a copy of the original Japanese owners manual but I can't read it.  It has some pictures that help but I can read Kata-Kania symbols.

Thanks again for you help.  If you would like more detail I can write a document that explains how to connect the electrical components.


Bud, not much more help here.  I just don't see enough to do a lot of work on them.  Sounds like you did a good job in ringing out the circuits!  I would imagine that the clock mechanism to which you are referring is the quartz timepiece.  If I'm not mistaken, it is a time only module with wires coming out to trip the music section on the hour and/or quarters.  It consists mostly of nylon gears and there is no lubrication or maintenance required.  Being a quartz crystal unit, it provides a very high frequency circuit which goes through a series of dividers until it gets down to one step per second.  I believe the original ones did have a frequency control, probably a variable capacitor.  If the modern ones are not keeping the correct time, there is probably a bind in the mechanics or the unit has become defective, and it has to be replaced.  The frequency is maintained through a range of designed voltage and will not vary.  The first thing to fail with these units is that they will not power the minute or second hand when in the area of the "9".  This is where the weight of the hand is producing the most resistance to move.

I would think that the only logic cards that would work with these units would be from Seiko/Rhythm.  And, again, I am sure they won't provide them outside their company.  I discussed with them obtaining parts for a unit I had in my shop.  They said to send it it, and made an offer to sell me an upgraded model with more songs.  

Thanks for the offers of the details, but the circuits on yours would most likely be different from many others.

John Newman  

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John Newman


As much as I would like to offer values of clocks, I am not a certified appraiser and will not venture into giving an unresearched guess. There is very little published information on what I consider to be the value of "modern production clocks". Considerations are what the clock originally sold for, the condition of the case and movement, and particularly the area in which you live, the demand and the economy. ALSO, WATCHES ARE NOT MY FIELD. However, I can advise the clock owner on proper maintenance of a clock to keep it running, small corrections and adjustments and how to move a clock without damaging it. I can also advise on obtaining parts for clocks. It helps if you can send any information on the clock movement which is usually found on the back plate of the movement. I have been a clockmaker for about 35 years and was plant engineer in the mid 90's and later operations and engineering consultant at Emperor Clock Company in Fairhope, Alabama. I now have my own clock shop.


One of my greatest accomplishments was traveling to China to assist a clock factory in building clocks to the standards which we required. With the proper specifications and quality control, some beautiful clock cases were built. The factory people from the wood carvers to the plant manager were very congenial, friendly and I left a lot of wonderful friends when I returned from my trips.

NAWCC (National Association of Watch and Clock Collectors) 30 years Prattville, Alabama Chamber of Commerce

Horological Times, a publication of the American Watch and Clockmakers Instute. Collaberated column author, with Photos and ideas for clock movement conversion article.

Associate of Science Mechanical Engineering Technology Emperor Introductory Clock Repair (Eventually taught a portion of the class after becoming employee)

Awards and Honors
Small Business of the Quarter (Prattville, Alabama) Leadership Class of 2009 (Autauga County, Alabama)

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