[time-nuts] Chelsea Chronoquartz dividers

[djl]

Isn't the 4 MHz crystal near the sweet spot for one of the cuts? A dim 
memory at best :-)
DJ

On 2020-09-11 11:57, Tom Van Baak wrote:
> Bill,
> 
> 4194304 Hz = 2^22 Hz so 22 flip-flops gets you down to 1 Hz. The
> binary divider is s similar to how the Seiko Beta 21 was designed. See
> [1] for an example of a clock that uses this frequency.
> 
> What's nice about the Omega Ships Chronometer shown there is that it
> has a LEMO 1PPS output so one can make precise measurements of the
> clock without opening it and without resorting to audio, optical,
> vibration, or magnetic methods. I have one here if you have any
> questions about construction, repair, or performance (measured against
> GPS).
> 
> /tvb
> 
> [1]
> https://en.wikipedia.org/wiki/Omega_Marine_Chronometer#4.19_MHz_Ships_Marine_Chronometer
> 
> 
> On 9/11/2020 10:30 AM, Bill S wrote:
>> A friend has acquired a Chelsea Clock Company Chronoquartz which was 
>> probably made in the 70's. He has measured the oscillator frequency at 
>> approximately 4.194304 MHz. He wanted to know what arrangement of 
>> dividers they used to run the 4 pole stepper motor to step seconds. 
>> Anybody know?
>> 
>> Thanks,
>> 
>> Bill_S
>> 
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at lists.febo.com
>> To unsubscribe, go to 
>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
>> and follow the instructions there.
>> 
> 
> 
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.

-- 
Dr. Don Latham  AJ7LL
PO Box 404, Frenchtown, MT, 59834
VOX: 406-626-4304