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.
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.
------------------------------------------------ Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA
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