I have an ancient Seiko quartz with a trimmer inside, and by adjusting it I was able to make it accurate to 30 seconds a year. But few cheap watches have them, including none of those I tried in this test.
There are two ways to do as suggested. The first is to make 'Benjamins' part of the technical facts during design. The second is to do the design, then let bean counters change the design per what they 'feel' is not worth the bucks. The latter is too often how GM cars are designed. Which is why a GM car needs two extra pistons to get the same horsepower as the competition. Which is why GM cars even in the 1990s required annual wheel alignment. Which is why GM cars would have what appeared to be computer failures when failure was really due to cheap connectors. Classic examples of failures when the design is modified after the design.
Two examples: how 'Benjamin' decisions become part of a successful design verses how 'Benjamin' decisions after application of technical facts makes bankruptcy.
Meanwhile, the technical reas> There is no technical explanation except that the technology that
IBM did a lot of things wrong with their PCs in terms of performance, upgradability and user friendliness, but their quality was second to none un until the end of the PS/2 line. Andy Cuffe
snipped-for-privacy@psu.edu
Because the processor in your computer might hang or busy itself with other things besides keeping time. It may also have something to do with the clock pulses your computer uses not being exactly divisible into real time.
look for a program called D4. It is a free download and will keep your clock synced to universal time. Also, Widows XP can sync to the same time servers that D4 uses. Both work great!
Why so many "it might be this" or "it might be that" or "time is updated from the internet"? Every posts says nothing useful AND does not answer the OPs question. OP even clarified the question when some replies were rubbish.
The answer -- technically -- was posted without speculation. Processor hangs obviously do not affect that clock operation - it one first learned how something works before posting. The OP posted this - a technical question that required technical knowledge before replying:
See that word "might" ? That word "might" means the poster does not know the answer and therefore should not have posted. Any> Because the processor in your computer might hang or busy itself
Who the hell made you the NG God who should say who should and who should not post a reply. In short, Fuck You!
Don't tell me that the time kept by your computer does not require a processor and that it does not ever hang because that is bullshit.
The fact that the OP asked the question leads me to assume that his clock on his computer not keeping accurate time is annoying him. Therefore, I recommended the Program called D4. It is a solution to the problem and it works.
What Happens and Why There is a "CMOS clock" in your computer which is powered by a tiny battery. As long as the battery is good, this clock keeps the correct time, and each time your computer is restarted, Windows98 reads its initial time from the CMOS clock. However, while Windows98 is running, it keeps track of the time on its own without continuing to check the CMOS clock, and keeping track of the time is not the only thing Windows has to do. The busier your system gets, the more likely it is to lose time. Generally, the longer you use your computer, the further behind it gets. When you leave your computer on for an extended amount of time, the Windows clock (displayed on the taskbar) may lose from two minutes to an hour per day.
Likely culprits Anything that makes your computer especially "busy" can take Windows' attention away from its time-keeping function and lead to this "losing time" symptom. If you're running lots of programs, or even just one or two very demanding programs, you may see the computer clock losing time. Furthermore, anything you are running which causes the computer to have to spend time "watching" for something to happen can also lead to a slow clock. Here are the most common culprits:
a.. Games and other video-intensive programs
b.. Screen savers and "scheduling" programs
c.. Internet chat programs (ICQ, IM, etc.)
d.. Playing MP3 files, CDs, or internet audio
e.. Anti-virus programs
f.. Processor-intensive applications
Why is speculation useless? Nobody can give one solid answer because the problem is not identical across all computers, nor is it always caused by one simple factor. I've learned a fair amount of interesting things from this thread, I guess you missed all that.
"do_not_spam snipped-for-privacy@my-deja.com" bravely wrote to "All" (27 Oct 05 09:34:24) --- on the heady topic of "Re: Why aren't computer clocks as accurate as cheap quartz watches?"
do> From: do_not_spam snipped-for-privacy@my-deja.com do> Xref: core-easynews sci.electronics.basics:145659 do> sci.electronics.repair:346469 alt.comp.hardware.pc-homebuilt:351295
do> w_tom wrote:
do> I have an ancient Seiko quartz with a trimmer inside, and by adjusting do> it I was able to make it accurate to 30 seconds a year. But few cheap do> watches have them, including none of those I tried in this test.
I bought a cheap $5 lcd watch years ago and noticed the circuit had the solder pads for a trimmer cap. After adding the timmer and adjusting, it was the most accurate timepiece in the house. When I came across another identical watch many years later I did the same thing to it too.
The adjustment was trial and error using CHU. Starting at the midpoint, I kept cutting the error in half either side then set it inbetween. Both keep great time, I never notice a difference even longterm, perhaps a second per month if that.
How did you adjust yours, with a pickup coil and frequency counter? I suppose that would be the logical way to do it but then again a counter could be off a tiny bit too. The NIST over the internet seems nice too but what are the sources of error with this?
A*s*i*m*o*v
... I worked hard to attach the electrodes to it.
Right on James!
That is how the NG's are suposed to work. But you get these trolls who think there answer is the only answer. They have closed minds.
And your answer was? or were you just posting to post.
In this environment speculation is just about all you have as the machine (subject) is rarely in your hands. Since then a phrase has been invented to take the place of that....and that would be...YMMV
But even worse, he posted
time
Just in case anybody is interested
And for the record, Tom, is relevant to the OP's question because it concerns your PC's clock keeping accurate time. It is a solution to the problem. What have you to offer?
That wasn't the question. The OP didn't ask how to solve the problem.
So what? I had offered an answer to that as well as offering a solution. Perhaps you didn't read that part of the thread.
Now, Had I said your pc's clock will run slow because magic trolls and ferries sneak in make adjustments to the master oscillator. That might warrant an attack. But the rest of this crap is just that, crap!
you see my mind is not one dimensional, I might take a question and expound on the answer to not only give a reason why this happen but also offer a way to correct it.
And by the way, my last comment was prefaced, "Just in case anybody is interested". Obviously you are not so the post was not intended for you. In other words, Bug Off, pedal on and get a life!
Your other post is classic of those who use emotion as if emotion was logic. I will pretend you did not post an outburst in the other post; in respect for your dignity.
Below is a partial description of how the computer's other clock works. It assumes time lost will also cause the computer's battery clock to change. Do you know they both use completely different circuits and oscillators (time bases)? That battery clock does not change no matter how many seconds or days the Windows (Operating System) clock changes.
This might be true if the system is not pre-emptive multitasking or if the OS itself crashes - which is rare enough to not be relevant:
Meanwhile, as an OS gains or loses time, the computer's battery clock remains unaffected. Again, you should have known this which is why your original post used the word "might". Well, at least this time you look up some facts before posting. But you did not obtain all facts. Loss of time by the OS does not change the CMOS or battery clock. Made obvious with simple hardware or BIOS knowledge. You are advised to first learn the basic circuit - as it was designed even in the original IBM AT. The circuit is based in a famous IC - Motorola's MC146818 and an equivalent IC from Dallas Semiconductor.
Not knowing how this battery clock works is not what you are criticized for. Furthermore an emotional outburst was not posted - a lesson you should learn from. Criticism is based on facts. You posted speculation AND you posted things totally irrelevant to what the OP was asking. Not just you. This thread is chock full of posters who only speculated and who did not answer the OP's question.
Now you are also being corrected for not learning all the facts about how the battery backup data time clock works. Your "Likely culprits" list is not based on knowledge of a
1984 legacy circuit that is standard in PCs. Gain or loss of time by the OS - using a completely different clock - does not affect the battery backup clock. This true in hardware today as it was in the original IBM AT. Those "most common culprits" in no way change the date time of a battery backup clock.What was do_not_spam_me ask> What Happens and Why
You apparently didn't read *all* the replies, but more to your question, a lot of people with too much time on their hands and too little knowledge to be useful feel compelled to type when you put a keyboard before them. Must be an ego thing...
No, I don't. Where do you see it?
UseNet is arcane and slow, so messages may take hours or even days to propagate through the system. In some cases, it is even possible to see replies before the original question. You cannot tell much about what posts someone else has seen from the time of appearance on *your* screen.
Could you have a look into how these clock are constructed.. ?
The battery backup circuit in a PC is a circuit originally in IBM AT - a legacy of that well established 1984 design using a Motorola MC146818.
To have posted as DBLEXPOSURE has, he should have first known about that circuit. A majority of posts in this thread are total speculation based upon no relevant technical knowledge. That is shameful if not irresponsible. One even claims the OS clock causes changes in a completely different oscillator - the CMOS date time clock. Again, one who did not first learn basic facts. Unfortunately too many people (often who are only programmers) somehow become experts on how hardware works. Had he even learned a PC's BIOS, then this would have been obvious.
DBLEXPOSURE demonstrates that many just know; cannot bother to first learn how hardware works. It is the difference between one who is product oriented (deals in reality) and the antonym of a product person - the MBA. DBLEXPOSURE posted wild speculation - even worse doing so without first reading a previously posted and technical answer. Two problems in his response are cited. But then he adds a third problem: learns only half of how a CMOS date time clock works; speculates that timing changes in the OS changes a date time clock.
First what he (and others) originally posted in response to do_not_spam_me's original question has nothing to do with the question asked by do_not_spam_me. Second, many of those posts all but admit they don't know - based in wild speculation.
At least, in a later post, DBLEXPOSURE attempts to learn how the CMOS date time clock works. But he still got it wrong. Those applications - "Likely culprits" - will not affect the battery backup CMOS date time clock. He should have known that even from facts that an inquisitive user observes.
BTW, Rick Yerger also criticizes DBLEXPOSURE for not answering the question. Rather than act product oriented, DBLEXPOSURE replies as an MBA:
Again he demonstrates no grasp of facts - instead using feelings as if his feelings were facts. I don't have anything to apologize for when I criticize what DBLEXPOSURE and others have posted. Wild speculation was misrepresented as fact - and did not even answer do_not_spam_me's question.
Two factors cause significant variati> Why is speculation useless? Nobody can give one solid answer because
The answers I found useful in the thread are: * Use internal capacitor to adjust for the crystal. * Provide stable voltage. * DS1387 (suns?) have a good track record. * Crystal chassi shall be grounded.
Useing these facts it should be possible to construct a fairly precise clock. A precise crystal with internal capacitor in shielded box powered by it's own linear voltage regulator should do it?
It could then countup a synchronous counter on positive flank. And be read on negative flank (and only then).
Regulator could use diodes to enable proper batteri/psu operation. Separate regulator for counter and crystal.
If there was an answer in this thread, I must have missed it. So many ideas, so few applications of the facts :-)
There are two clocks in a PC (I don't know MACs) A hardware one, and the software clock. When the PC boots, the BIOS reads the hardware clock, and the OS asks the BIOS what time it is. From there on, good old windows or whatever is doing the clock counting, using an interrupt timer. Given the sloppy programming, and the inability of windows to pre-emptively multitask, the software clock is not going to be very accurate. Just open your time settings screen and watch the second hand on the clock. That will show you right away that not only is windows terribly inefficient, it is unable to update the clock consistently, and accurately, even when it is 'idling,' due to system overhead, poorly implemented.
Each time you power down or restart the PC, the hardware clock is read, and it is more accurate than the software, although still subject to crappy crystals and poorly implemented devices. If you leave the computer on for days at a time, a restart will probably get the clock back to a more accurate setting, but not necessarily much better.
The question of why the PC clock is so inaccurate, and yet more expensive than a cheapo watch is simply a matter of "how ya gonna get the information out of the cheap watch, and into the PC?" The clock itself, and the crystal are only a portion of the hardware required by a PC to know what time it is. The additional requirements increase the sicon die size, as well as the complexity of the design, so the higher cost is to be expected. If you can get the time out of a cheap watch, in binary form, at the proper levels, and the proper timing specs, without raising the price of the $1 watch, a lot of people would like to hear from you ;-)
There are many sources of RTC boards that plug into a PCI slot and take over the timekeeping for highly accurate applications, and of course, as so many pointed out, apps the use the National Standards are free and easy given net access.
Just another 3.5 cents.
Mark
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