Fascinating.

1. Does anyone know if they have different models for 50 and 60 Hz regions (or 
is the internal software smart enough to differentiate)?

2. Any else think this is a questionable approach for a watch that is heavily 
advertised (at least around here) as being great for the boating set?  If they 
have lights, they are usually DC...imagine being on a nice long distance yacht 
voyage, and your watch (highly accurate at home) just gets worse and worse as 
the days go on.

3. Based on the industrial frequency meter I have on our power line here in RI 
(US), the absolute frequency never varies more than +/- 0.04 Hz, and my 
Heathkit clock (uses the power line for timekeeping) never varies more than 4 
seconds from the GPS based clock sitting next to it.  On a trip to Scotland, 
using the same meter, I observed variations as large as +/- 0.1 Hz (not a typo, 
from 49.90 to 50.10 Hz). FWIW

Tom Frank, KA2CDK

On Apr 20, 2011, at 9:43 AM, tom jones wrote:

> Most if not all Citizen ecodrive watches are disciplined by 60hz light 
> flicker that average
> the 60hz light flicker over approximately 10 days before a rate adjustment is 
> preformed.
> 
> I have four citizen ecodrives;
> 
> Plain jane quartz analogue ecodrive with mechanical calendar that is 60hz 
> disciplined.
> 
> Stainless steel skyhawk ecodrive ana-digital that is 60hz disciplined. I've 
> monitored this one
> for over a week it was holding  13 miliseconds for over a weeks duration (off 
> the wrist mode) compaired to my cesium and ribidium references and got 
> distracted from futher measurements of this citizen skyhawk as I was consumed 
> with other measurements and comparisons between loran gps cesium ribidium and 
> other watches.
> 
> Blue angles citizen skyhawk ana-digital that half the time seems to be 60hz 
> disciplined and other times unsure.
> This blue angles citizen skyhawk has the same movement as the stainless steel 
> skyhawk which is definately 60hz disciplined.
> I suspect this blue angles skyhawk that I purchased out of the country could 
> have 50hz and 60hz dicipline modes?
> 
> My fourth citizen ecodrive is the stars & stripes forever yacht timer 
> ana-digital which is 60hz diciplined.
> This watch reboots every feb 28th at midnight to utc time zones and jan 1 
> 2004 (not sure of the exact year is crashes to) some kind of leap year bug!
> 
> Only unexpected temperature changes experienced by the ecodrive citizen 
> watches produce significant error 
> (.5 to 1 second over several days of temperature varation) there rate will 
> correct after an approximate 10 day time constant.
> 
> Many wrist watch forums make reference to citizen ecodrive rate accuratces 
> remarking that citizen uses some propriatary rate techniques. It's simply 
> 60hz light flicker received at the ecodrives solarbattery/photocell.
> 
> I would recomend when setting your citizen ecodrive watches to set them 2.5 
> to 3 seconds fast if worn continous because that is approximately how much 
> time will be lost before its rate gets compensated the first time.
> 
> A Great Day to All , Tom
> 
> 
> _______________________________________________
> time-nuts mailing list -- [email protected]
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.


_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.

Reply via email to