J
John Fields
The problem is getting a timer.
The problem is getting a timer.
The problem is getting a timer.
And I think it has already been established that the kind of accurate
timer I need doesn't exist(or no one here knows of one).
Richard said:http://www.google.com/search?q=1/100+second+timer
#2 on the list...
http://www.meylan.com/1_100sec.html
12 models with 1/100 displays and up to 100 hours. Whether they're
really 99.99992%+ accurate is for you to determine.
Now, these were very easy to find. They meet your limited "simple"
specs. Seiko is a name brand in sports timing, and the printer model
has it all.
I'll politely assume that surely you searched Google first, found these,
and determined they were inadequate by merely looking at them. So, what
makes these unsuitable?
Richard said:http://www.google.com/search?q=1/100+second+timer
#2 on the list...
http://www.meylan.com/1_100sec.html
12 models with 1/100 displays and up to 100 hours. Whether they're
really 99.99992%+ accurate is for you to determine.
Now, these were very easy to find. They meet your limited "simple"
specs. Seiko is a name brand in sports timing, and the printer model
has it all.
I'll politely assume that surely you searched Google first, found these,
and determined they were inadequate by merely looking at them. So, what
makes these unsuitable?
Richard said:http://www.google.com/search?q=1/100+second+timer
#2 on the list...
http://www.meylan.com/1_100sec.html
12 models with 1/100 displays and up to 100 hours. Whether they're
really 99.99992%+ accurate is for you to determine.
Now, these were very easy to find. They meet your limited "simple"
specs. Seiko is a name brand in sports timing, and the printer model
has it all.
I'll politely assume that surely you searched Google first, found these,
and determined they were inadequate by merely looking at them. So, what
makes these unsuitable?
Jim said:You've said that you just want a timer that will run over a period of
six hours with 1/60 sec accuracy.
You've said that all you want is a simple clock display that reads out
seconds.
You've said that it needs to just start at an arbitrary start time and
count from there.
Yup.
None of these goals is particularly hard, but to get that accuracy
you'll need to buy some sort of commercial clock with a time display
and mate it to a frequency source (which in this industry is also
commonly called a "clock", further confusing this question) that is
more accurate than such timers usually come with. Or, if you have real
money to spend you can buy something with a real frequency standard
(clock) inside which could be purchased with a digital clock display.
The price for something like this could be anything from $2500 to
$40,000. This whole range is much more accurate than you've asked for,
but it seems unlikely that anyone makes something that meets just your
minimum accuracy requirement.
The problem that I see is that you've not asked for any kind of
electronic input or output for the timer, which makes most of us
wonder how you expect to be able to use 1/60 sec accuracy while just
doing this by eye.
If you're planning to use electronic start and stop signals, then you
can get much better accuracy than 1/60 sec.
So this leaves us confused about what it is that you really want/need.
It's not that people here are trying to be difficult; it's that they
are trying to be helpful, but the specs of your request, taken as a
whole, just don't seem to make sense.
So if you explained a little more, without giving away any of your
secrets, then you will probably get the answer you're after.
Ian said:GPS recievers.
I've seen some with an alarm function.
However, 1/60th of a second in 6 hours isn't impossible to do otherwise.
In sci.electronics.repair Jim Adney said:None of these goals is particularly hard, but to get that accuracy
you'll need to buy some sort of commercial clock with a time display
and mate it to a frequency source (which in this industry is also
commonly called a "clock", further confusing this question) that is
more accurate than such timers usually come with. Or, if you have real
money to spend you can buy something with a real frequency standard
(clock) inside which could be purchased with a digital clock display.
The price for something like this could be anything from $2500 to
$40,000. This whole range is much more accurate than you've asked for,
but it seems unlikely that anyone makes something that meets just your
minimum accuracy requirement.
Well, you have already hinted at it yourself.
What are the odds that a stand alone stopwatch will be anything close
to 1/60th of a second of the correct time at the 6 hour mark?
And we all know that 1/100th of a second on a hand held stopwatch is
nothing but a marketing gimic.
The problem is the criticizing of my needs and the suggestion of
alternatives by those unfamiliar with the project. The initial question
was simple, and I thank those who gave me their best answers.
This is actually much simpler than the original project which involves
more than just a timer, but the ability to record the time of each of
four (joystick)input activations/deactivations, which could number over
300 over the course of between 2 and 3 minutes. And then play them back
the same way.(Thereby replicating my moves with that 1/60th of a second
accuracy). But since I am having such difficulty with this, the
original needs are definitely out of the question anytime soon.
In said:I said in my very first post that I was looking for an electronic timer
that is accurate to within 1/60th of a second over the course of 6
hours. Then the thread turned into questions concerning my project and
assumptions as to why what I ask for wasn't logical.
I think for you to measure an event with an accuracy of 1/60th of a
second, you need to take measurements at least 120 times a second (well
known theorem, I forgot the name).
No, that would by Nyquist. Shannon limits the data rate, based onThat would be Shannon.
I think for you to measure an event with an accuracy of 1/60th of a
second, you need to take measurements at least 120 times a second (well
known theorem, I forgot the name).
... I thought that there might be an affordable timer that would somehow
keep it's accuracy by via 60Hertz AC. But I guess not.
Rich said:Well, Jesus Aitch! Why didn't you just say so? There's probably a
dozen people here who could design a joystick tracker with millisecond
accuracy, and record switch closures to microsecond tolerances. I'd
lighten up a bit on looking for a coincidence detector, which is not
going to happen unless you can physically hack the game you're trying
to hack.
If you're looking at reaction time stuff, then you'll have to find
a biology or anatomy group, although I'd still venture to guess that
most people who are conversant with this level of electronics
probably know something about nerve impulse propagation and
electromyelographic interfaces. Heck, a year or so ago, I was being
tested for neuropathy, and they taped some electrodes that look
very much like EKG or EEG electrodes to my legs, and the nurse (or
lady doctor - we didn't get into that) took a hand-held that looked
so much like a stun gun that when I said, "Stun Gun???" she said,
"That's what everybody says." They stunned me, and they took
readings of my neural response. Diagnosis: Alcoholic Neuropathy.
Oh, well.
You might also look into the source code for "MAME" - Multiple
Arcade Machine Emulator. I play Mr. Do! and Bubble Bobble regularly,
and am considering something much like your project, to see how the
software uses joystick/button actions to modify its own algorithm!