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Warning. Several people have reported an AUTOEXEC.NT error when trying to run GeoClock. We think we have tracked this down. Click here for help.

It is now possible to download the GeoClock-Pro

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Last File Update 2006/03/27 Last Site Update 2006/02/27

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GeoClock screen shot

GeoClock 8.4

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GeoClock Home Page

2218 N Tuckahoe St
Arlington VA 22205

voice 703-241-2661
FAX 703-241-5809











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Privacy Statement

GeoClock 8.4

GeoClock screen shot

About GeoClock

GeoClock shows the current time (based on your computer's clock) with a high quality map of the earth. The current sun position is displayed, and the parts of the earth in sunlight and twilight are highlighted. This display is automatically updated every few seconds. Local sunrise, sunset, the sun's azimuth and elevation, and times around the world are also displayed. A variety of map backgrounds and other options are available.

GeoClock is distributed as shareware. With registration you get the latest versions of the programs, 45 maps, zoom, distance measuring, local time displayed next to the city names, and immediate map display. GeoClock comes in DOS and Windows versions, and both are included with registration. The Windows version works with Win3.1x, WFW, Win9x, WinME and WinXP. The Windows version also includes Screen Saver and Wallpaper modes.

System Requirements

The DOS version requires a VGA and 640K, and will run on an 8088. However, we recommend at least a 386SX/25 for satisfactory performance. The Spinning Globe program runs best under DOS with at least 4 MB Extended/Expanded Memory and a 486/25

The Windows version requires a VGA and 4 MB, but we recommend at least 800x600x256 display and a 486/66. It will run on both Win3.x and Win9x/ME/XP.

We do not have versions for any other platforms.


GeoClock comes in a basic version and a professional version, and both are available with a HAM radio add-in package.

GeoClock-Pro includes both the registered DOS and Windows versions of GeoClock, plus more than 500 maps covering each US state, Canadian province, and world country, plus about 150 city level maps, and a variety of larger scale maps, the spinning globe program, about 100 extra maps (these are unsupported and may be of unique interest, but are included just because some people want everything), and a variety of utility programs to customize GeoClock data bases. It is distributed on CD, or can be downloaded.

The GeoClock basic includes both the registered DOS and Windows versions of GeoClock, plus 45 maps covering the world at a larger scale. It is distributed on 3.5 inch floppy disks, or can be downloaded.

A HAM radio package is available as an add-in to either package. It is distributed on 3.5 inch floppy disks or can be downloaded.


ACE-HF (Animated Communications Effectiveness, High Frequency) is a new product based on the proven VOACAP program with a new interface and display routines based on GeoClock. Click the icon to read more about ACE-HF.

Downloadable files
All these files are ZIPped - you should unZIP them into a directory specifically for GeoClock

Click to download
GCKWIN84.ZIP 656 Kbytes
2002 Feb 1
This file contains all you need to run the Windows (Win16) version of GeoClock, including four maps. 32 bit version?
2006 Feb 27
This file contains contains the changes to data files required by Indiana's moving into the 20th century! (fixing some time zones) These changes go into effect 2006/04/02.
GEOXTR84.ZIP 194 Kbytes
1999 Jun 18
This file contains some supplemental files - three additional maps and the zip code table
GEOCLK84.ZIP 364 Kbytes
2002 Feb 1
This file contains all you need to run the DOS version of GeoClock.
2006 Mar 27
This file contains the latest version of the GeoClock time zone table.

This is the spring 2006 update to reflect what is known of the world's time zones. It reflects the moving of Indiana to the 20th century, a one time only change in Australia to facilitate the Melbourne Commonwealth Games, Tunisia summer time, and changes Cuba's DST back to US dates, Brazil, and fixes an old error for Guyana. You should be sure you have GeoClock 8.4 or higher.

You should download this periodically to ensure you have up to date time zone data.

GEO84D.ZIP 482 Kbytes
2006 Feb 27
This intermediate version of the GEOCKWIN.EXE which seems to solve some stopping problems and clock problems on ME, XP, NT5, and 2000, and charges to the internal ZIP data base for Indiana. It includes only the EXE and HLP files, so you will need all the other GeoClock files to test it. It is little different from BETA84B. Please advise results. See FAQ.
MAP612.ZIP 25 Kbytes
2001 Oct 09
This is a more detailed map of Afghanistan. It will only work with registered versions of GeoClock
MAP734.ZIP 25 Kbytes
2003 Mar 21
This is a detailed map of Iraq. It will only work with registered versions of GeoClock
MAP3162.ZIP 31 Kbytes
2003 Dec 07
This is a correction to the Johannesburg map on the CD. While it is correct in my master file, all three copies on the CD are defective.
UPDPRO84.ZIP 1779 Kbytes
2002 Feb 02
This file contains everything that has changed or been added to the GeoClock Pro (CD) version was first issued. If you have a CD (GeoCLock-Pro) version less than 8.4, unZIP this file into the directory where you installed it.
1999 Jul 10
This file contains add-in files for GeoClock, including the Dateline and the Nunavut border. See the INCLUDE.TXT file included for instructions.

GeoClock Author.
Sun directly overhead, Serengetti NP, Tanzania
2004/09/29 12:55 East Africa Standard Time