Free Atomic Clock is a very simple program to use. As the name implies, it is freeware. You may use, copy, redistribute, or sell this product in any way you wish provided that this documentation is included with it.
When you first launch Free Atomic Clock you will see this main user interface:
Free Atomic Clock will display your computer clock's current time and date. As with most clocks, your computer's clock may be off by several seconds or even several minutes.
To get the exact time of day to the nearest second, press the 'Set Clock' command button. Free Atomic Clock will then connect via the Internet to an atomic clock time server maintained by the National Institute of Standards and Technology's (NIST) Time and Frequency Division, and reset your clock to the exact date and time. Free Atomic Clock will then tell you how many seconds your computer's clock was off by.
It's that simple.
It takes a very short amount of time for the atomic clock's data to be sent to you over the Internet. To speed things up, you may want to choose to connect to the time server that is closest to you. To do this, press the 'Preferences...' command button to display the 'Preferences' dialog box. Select the time server that is closest to your location, then press 'OK'.
There are five government time servers in Boulder, Colorado (including one maintained by the University of Colorado), two in Gaithersburg, Maryland, and one in Redmond, Washington. Some private companies (such as AOL) also maintain atomic clock time servers (but not actual atomic clocks), but I did not include them because I figured that any company could decide on a whim to take down their time server if it became too costly. I wanted my program to be as reliable as possible.
I will try to keep Free Atomic Clock updated in case any bugs are discovered. (See the FAQs section below for information about potential bugs.) The newest version should normally be available at my web site: www.jparsons.net. To view the Web site address or Free Atomic Clock's copyright information, right-click on its menu bar and select the 'About Free Atomic Clock...' menu item as shown here:
If you like, you can confirm that your computer's clock is set correctly by double-clicking the time in the System Tray to display the 'Date/Time Properties' control panel. The problem is that although your computer's clock is now set correctly, Windows hasn't yet told the System Tray to display the correct time. The correct time will be displayed within one minute.
Many companies have firewalls and proxy servers. Free Atomic Clock was not written to handle proxy servers. Also, your company's firewall may be blocking port 37, which Free Atomic Clock uses. Some atomic clock software programs use port 13 or port 123 instead, but firewalls often block those ports, too.
NIST requires atomic clock clients to use one of ports 13, 37, or 123.
You can always view the exact time at www.time.gov. This Web site works best if you have the Java Plug-in installed on your computer. Unfortunately, some corporate firewalls block Java applets.
I have tested Free Atomic Clock quite thoroughly and I have not found any bugs in a while. However, Free Atomic Clock is in its first version, and it was written and tested on one computer running Windows 98, in one time zone, during daylight savings time, so it is quite possible that I missed some bugs.
If Free Atomic Clock sets your computer clock's time to be exactly one hour or several hours off (with the minutes correct), first check to make sure that your 'Time Zone' settings are set correctly in the Windows 'Date/Time' control panel.
If you believe you have found a bug, please e-mail information about the bug to freeatomicclock@jparsons.net. I will fix any bugs I can reproduce, and I will post any fixes to www.jparsons.net.
I am not distributing the source code with the software because not every user wants the source code. I will keep the source code posted at www.jparsons.net. Free Atomic Clock was written with Visual C++.
Yes! Absolutely! Anyone may use, copy, redistribute, or sell Free Atomic Clock in any way they wish provided that this documentation is included with it. You do not need to get explicit permission, nor do you have to pay me any royalties. You are not licensing a copy of the software; you OWN your copy of the software and may do whatever you wish with it and all derivatives of it. I still own the copyright, however.