I have to ask since we are going all doomsday preppers. Do you still have a magnetic compass in your wheelhouse?
[QUOTE=PaddyWest2012;132432]Very nice but these are a little more my speed:
And, of course, by speed, I mean PRICE.[/QUOTE]
Seven half turns every day at the same time, just about 0430 in my case. And donāt let it run down in port when youāve switched to port watches. Memories of my days as 2nd mate. Years ago, when we actually made part of our living by navigating with a sextant. Just about every day. Even the days with some overcast and a ragged horizon. Oh yeah, and worked out course and distance using trigonometry, spherical or plane. We worked with nice things then: tools, concepts, ships, etc.
[QUOTE=PaddyWest2012;132450]I was curious about that myself so I looked into it. According to the people who make $30 mikey mouse watches theyāre accurate to +/- a second a day. Thatās quite an error after just a couple of weeks.[/QUOTE]
In my experience, 4 or 5 seconds a day on the chronometer was common. It was consistent, but it was still 4 or 5 seconds lost or gained (usually, lost) per day.
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[QUOTE=pelicanhook;132643]Seven half turns every day at the same time, just about 0430 in my case. And donāt let it run down in port when youāve switched to port watches. [/QUOTE]
And if you do let it run down in port, re-start it with the error it would have if it was wound daily (or so Iāve heardā¦)
[QUOTE=jdcavo;132671]
And if you do let it run down in port, re-start it with the error it would have if it was wound daily (or so Iāve heardā¦)[/QUOTE]
That was if you didnāt want the old man to know. By the book you restart as close to possible to UTC. To restart youād give the whole thing a quick 1/4 turn. As Y.S. says, donāt ask me how I know. Of course that way your sins were recorded forever in the book
I have a cheap, ($60) reliable, Casio that receives a time fix every night from the atomic clock in Colorado. Itās more accurate than any ship board chronometer and stopwatch combination that I have ever used. Harrison would have been amazed!
[QUOTE=Lookout;132688]I have a cheap, ($60) reliable, Casio that receives a time fix every night from the atomic clock in Colorado. Itās more accurate than any ship board chronometer and stopwatch combination that I have ever used. Harrison would have been amazed![/QUOTE]
I picked up one of those myself about 5 years ago but I canāt make the damn thing work! Iāve gotten it to pick up a time signal and fix its time MAYBE twice in the 5 years that Iāve owned the damn thing. Iāve read the instruction pamphlet about a thousand times, I do everything it says, I put it by the window at night, where/when the reception is supposed to be maximized but the P.O.S. just runs itself into the ground with not so much as a glimmer of radio signal from any of its potential sources! If it worked I might not be having this conversation about chronometers at all, but since its got me vexed Iāve lost all faith in such āradio-controlledā accoutrements!
Itās because youāre in Maine, chummy.
Evah notice those weather channel types on the television standing smack dab in front of the state of Maine while up in front of the map? Same thing.
Damn thing donāt werk in no othah pahts oā the country neithah, theah bub.
Well aināt that a wicked pissah.
Correct your Casio like I do ā¦ WWV
[QUOTE=Flyer69;132692]Itās because youāre in Maine, chummy.
Evah notice those weather channel types on the television standing smack dab in front of the state of Maine while up in front of the map? Same thing.[/QUOTE]
There is a coverage map here. It does look like Maine has poor coverage but my clock from Radio Shack gets a signal here in Southern Maine. I donāt think you would get a signal out to sea though. Plus it would be hard to get a daily rate if it corrected at random times. The cheap Casio with a known rate would be a better bet.
[QUOTE=Kennebec Captain;132704]There is a coverage map here. It does look like Maine has poor coverage but my clock from Radio Shack gets a signal here in Southern Maine. I donāt think you would get a signal out to sea though. Plus it would be hard to get a daily rate if it corrected at random times. The cheap Casio with a known rate would be a better bet.[/QUOTE]
I have long suspected that my little radio controlled gidget is a defective unit (probably a communist plot of some type) so I would not be the least bit surprised if it was not at all the fault of the radio signal, or of my operation of the device, that has led me to such frustration. Someday when Iām bored and walking near a Radio Shack I may try and procure another, different, device and see if that treats me any better.
[QUOTE=PaddyWest2012;132706]I have long suspected that my little radio controlled gidget is a defective unit (probably a communist plot of some type) so I would not be the least bit surprised if it was not at all the fault of the radio signal, or of my operation of the device, that has led me to such frustration. Someday when Iām bored and walking near a Radio Shack I may try and procure another, different, device and see if that treats me any better.[/QUOTE]
Yeah, they are a cool gadget, they are widely available and not very expensive. Info from the NIST here.
They say that the mark of character in a man is that he can admit when he has been wrong. I have been purely, and unadulteratedly, wrong. I recently stumbled upon an old Casio quartz digital watch that I had forgotten about. I know, without a doubt, almost to the exact day, the last time that I set this watch to an atomic clock. It was mid-August, 2013, although I do not remember exactly what day. Whatever day it was, it was still close to 7 months ago, give or take a few days. After 7 months of sitting on a shelf in my bedroom it is precisely ONE second slow. ONE SECOND. AFTER SEVEN MONTHS.
Now, granted, it was sitting on a shelf at a fairly constant temperature of 60-65ĖF. I have no doubt in my mind that this fact contributed directly to its almost unbelievable accuracy over the last 7 months. Had this watch been in regular use, and been taken on and off my wrist every day, I have no doubt that the temperature fluctuation would have contributed to an even greater difference in time from the atomic clock at Fort Collins, Colorado. NEVERTHELESS, it is clear that quartz watches, at the very least, have the capability to maintain time VERY accurately over great spans of time. This is not the accuracy that I was led to believe from various online sources about the nature of quartz watches. Clearly, these sources do not speak for every quartz watch.
As long as we all keep our watches somewhat regularly set to an atomic clock, I am confident that celestial navigation will remain a perfectly acceptable backup system to GPS systems the world over.
^ You are correct that many if not most quartz watches are much better then the +/- 15 seconds a month.
Do you want the accurate time or do you want an accurate watch? An accurate time can be determined from an inaccurate time piece with a known rate.
An important characteristic of a quartz movement watch is that the daily rate (amount gained or lost per day)i s very stable. A watch with a know error which gains precisely 15 seconds a day could be used to determine the correct time though it would be inconvenient for daily use.
[QUOTE=PaddyWest2012;132852]
As long as we all keep our watches somewhat regularly set to an atomic clock, I am confident that celestial navigation will remain a perfectly acceptable backup system to GPS systems the world over.[/QUOTE]
You explicitly said we were not discussing this, but C nav is not an acceptable back-up for GPS for commercial shipping.
[QUOTE=Kennebec Captain;132860]^ You are correct that many if not most quartz watches are much better then the +/- 15 seconds a month.
Do you want the accurate time or do you want an accurate watch? An accurate time can be determined from an inaccurate time piece with a known rate.
An important characteristic of a quartz movement watch is that the daily rate (amount gained or lost per day)i s very stable. A watch with a know error which gains precisely 15 seconds a day could be used to determine the correct time though it would be inconvenient for daily use.
You explicitly said we were not discussing this, but C nav is not an acceptable back-up for GPS for commercial shipping.[/QUOTE]
The trouble I still have with quartz watches is that theyāre supposed to be subject to a change in their rate because of temperature. I do not wear this particular watch regularly so I have not experienced this first hand but if what they say is true then I would find the idea of an unsteady rate unsettling. Still, I have clearly experienced the watchās ability to keep excellent time under at least one set of conditions. Knowing that it at least has the ability is grounds enough for confidence.