cazalea
[Seiko Moderator]
20825
Excellent question!
Here's the answer:
The normal radio-controlled clock queries the NIST RADIO signal once a night, usually 2-4am. It uses that signal to correct itself. It does this once a day (to save battery life) and doesn't care if it misses a day or three.
In my case, in SoCal, we don't get the signal well and my cheap clock always misses daylight savings changes. I have to put it outside in the driveway overnight.
Whereas the ESE master clock is locked not on a weak radio signal, but triangulates on up to 6 satellite GPS signals and is always reading. That's shown by the green light GPS LOCK on front of the clock. If there is a momentary loss, the light goes out and if there is an error in the format of the signal, a red light illuminates.
If the signal is lost, the clock depends on its internal quartz clock. There are various levels of accuracy depending upon what you want to pay. The one I have is an old model but the highest accuracy. You can buy one with 2-3 seconds a week precision, but the spec for the 185 is drift of less than 33msec a day or about a second a month if all the satellites were down. There's also a uninterrruptable power supply battery inside to keep it running if power goes out (only about 4 hours though).
There's a fascinating brochure from the people who run our reference clocks (paid for by our tax dollars) and it explains about radio-controlled clocks.
click here for radio control clock info from NIST
Thanks for reading along on this somewhat watch-related topic!
Cazalea
This message has been edited by cazalea on 2011-04-05 21:35:48
Pondering My Pointless Purists' Pursuit of Precision (nay, perfection)
alas if you get your time off of your mobile phone, you might not understand this obsession, but it comes from the saying "man who has two watches never knows what time it is" I resolved to solve this problem, with a "atomic clock" that turned out to be e...
Can I sync to your MASTER CLOCK through the internet?
It could be our PST. Purists Standard Time! What a setup! Thanks for sharing.
Well, very impressive...
... but I am happy enough with my SEIKO Quartgz Astron, which is rated 10 sec per year. Since my purchase several maonths ago, I check often with the internet time.gov , it hasn't divereted even a half second. And that is my reference "clock" for my watch...
Audi/Video equipment master clocks
Hi Ken, Yes, you are right there is another way to use the term master clock . It also appears in a studio for recording or broadcasting. However now we are talking about master clocks that run equipment as opposed to the ones I described earlier which ar...
:-)
I have modified all my digital equipments to accept single clock signal from the handmade master clock (not by me, though) so that each equipment runs on single clock signal. Note that the clock does not have to be accurate like Astron for this applicatio...
A little info for clearer view
I used to work in a broadcast station, a post production studio and the audio mixing room. Let me try to give a simple explanation to our reader why do we need all there crazy equipment. The purpose of having a 'master clock' although in the industry we o...
i love your madness!
This is the reason why you come to a forum like this! Awesome! I learnt something and you may have just inspired me to make contraption that wont work J.
Nice setup
Nice setup, I use to run a similar system. A friend of mine did some work at NIST on their Quantum Logic Clock. It takes something like 3.5 billion years before it'll lose or gain 1 second. That is a time keeping system I can get behind.
questions, questions...
I am only slightly familiar with Master Clocks and their purpose, but my question concerns yours in particular. The correction signal comes from GPS satellites...but what is the 'escapement' in the unit itself? 'normal' quartz? Temp compensated quartz? Or...
oscillators
Not sure about the ESE unit cazalea has but the time servers I've managed in the past used a rubidium oscillators to maintain accuracy for several months in case of a GPS outage.
Excellent question!
Here's the answer: The normal radio-controlled clock queries the NIST RADIO signal once a night, usually 2-4am. It uses that signal to correct itself. It does this once a day (to save battery life) and doesn't care if it misses a day or three. In my case,...
Gotcha...
So the internal quartz is beating away at whatever frequency, with constant correction by comparing signals from GPS satellites. So in essence this is actually timed from the Rubidium oscillators (that romanv mentions above) that the GPS satellites carry....
Oh boy, I know how you feel
I've been thinking about doing that. Especially since the time I found out that radio controlled clocks are not that entirely relable. Now I use two for reference + streming from the interne,t just to be dead shure when Im setting The time of my mechanica...
I am amazed that you were not able to hide this from your wife
and I am going to have to re-read your post to make sure I got everything straight. Best regards, George
Stay right where you are....
The men in white suits are coming for you as we speak. They have a nice padded cell waiting for you. By the way, this cell has 50 embedded wall clocks ALL showing different times. Regards, Richard.
Oh i'd like to have a set-up like that in my house one day!
Thank you for sharing it with me and showing me a possiblity as to how it can be done! Cheers Stephen
I LOVE IT...(hate to scream)..
Wow! And my wife always rolls her eyes when I time my pieces (and hers) to the time.gov or emerald time app on the iphone! What a setup and thanks for the detailed info. This leads to another discussion during our lunch at Arry's with Dr. No. With wat...
Crazy! You certainly have a lot of place in your home.
I still wonder where I could put this kind of stuff at my home, where I don't even find a place for an hyopthetic Atmos. Best, Nicolas. This message has been edited by amanico on 2011-04-06 08:45:12
Nicolas, my Atmos is at the repair shop, so I have space
for all the satellite clock displays. Remember now I have to find a way to place them everywhere in rooms without ruining the house decor... a much harder task!
Great setup
I envy your setup. You took precision to a new level. Just when I was so happy with an app for my iPhone (Emerald Time - is free) that averages the time of four NTP time servers!! Cheers
Awesome precision...
I'll have to a review of my new Bulova Precisionist one of these days, spot on after a week. A quartz without thermo-compensation, just high frequency accuracy. Makes me wonder how long the battery will last. Thanks for the 'atomic' timeout, very cool...i...
Excellent - love it:
Congratulations - a fantastic set up. I am in full obsessive respect of your set up! It might be fun if you could tap that internal oscillator to show you fractions of a second; say a run-up in hundredths...but then what is the best method to sync analog ...
literally LOL
I can't wait to show this to my wife, so that she knows that I am not NEARLY as crazy as some others. Of course, she knows about this forum, and will simply pool all of us together as being equally obsessed. thanks for the post, can't wait to hear your ne...
WHAT THE HELL!!!!
That is awesome! I set my watches to a computer, and will wait until the seconds hit zero in order to synch up as accurately as possible. My wife makes fun of me constantly, but now I can show her this to prove I am not as nuts as she thinks. Very cool, a...
tht is awesome setup
and can warehoused with current hi-fi system and disguise them as hifi equipment!! if i am looking for time and date accurancy, but not to the fanatical level as you, and have space for just one "stack", with a budget not exceeding usd1500....what should ...
you are totally insane, but i love all the gadgets :)
i find a website with atomic time specific to my postcode is accurate enough for me, but i'm not in your league Mike. if thats your time telling kit i dont want to see your audio equipment have fun G
Stereo? Those new-fangled 2-speaker systems?
Although I use this MIH-powered tube amp at times, I normally rely on Luxman components, Klipsch speakers, and my iPods Mike This message has been edited by cazalea on 2011-04-07 16:58:56...
