TNT is free software. You can compile it from source code, or you can install a pre-compiled binary distribution. While most Windows users expect a binary distribution, many Unix or Linux users can build and install from sources. This section will describe both approaches.
TNT was originally developed to run on SPPDG workstations running HP-UX, and depends on several packages that are installed and maintained a the SPPDG. TNT has been ported to Linux and Windows, and an installation kit produced which should make it relatively straight forward to install the software on similar workstations or PCs.
TNT requires a functional installation of Tcl and Tk with several extensions, including BWidget, Incr Tcl, and Iwidgets. You will need to install all of these packages in order for TNT to function correctly. TNT expects to be able to find the wish windowing shell in your command path.
You could compile and install these packages from the freely available source code hosted at Sourceforge. Specifically, you can acquire them from http://tcl.sf.net/, http://tcllib.sf.net/, and http://incrtcl.sf.net/. You will need an ANSI C compiler, such as the GNU Compiler Collection from http://gcc.gnu.org. You should be able to use the Microsoft Visual C++ compiler or MinGW for Windows systems. You may find this an enjoyable challenge, or, if you are not a programmer, you might find the process difficult and frustrating.
Alternatively (and highly recommended), you can install a freely available, pre-compiled Tcl and Tk package from ActiveState, which includes all these extensions. The ActiveTcl distribution is, in fact, installed on SPPDG workstations and PCs. Unfortunately, while the ActiveState packages are free to use, we are not permitted to distribute the packages with TNT. You can obtain ActiveTcl for Windows, Linux, Solaris, or HP-UX from http://www.activestate.com/.
The Windows distribution includes a Tcl/Tk runtime along with all the extensions necessary to run the application. So you don't really need to download and install ActiveTcl or other Tcl/Tk distributions to make TNT work on your PC. But Tcl is so much fun to use, that you really ought to consider getting a copy.
TNT has a basic Windows installation program. Just click on the installer file, accept the GPL license, specify an installation location, and let it do the work. Installing TNT does not require administrative priviledges on Windows 2000 or Windows XP, but if an administrator performs the installation, then the package will be available for all users.
The installation program will create a shortcut to run TNT. You may want to copy that shortcut, and modify the ``Start In'' directory to a location where you normally work with transmission line simulations.
Download and install ActiveTcl from http://www.activestate.com/. This gets you Tcl, Tk, BWidget, Incr Tcl, Iwidgets, and a lot of other cool stuff.
If you have a binary distribution, just copy the TNT directory tree from the installation kit to a location from which applications are normally run. This could be /usr/local/ or a personal subdirectory or some other location. Make sure that the directories for wish and .../tnt/bin are in your path.
To build TNT from sources, unpack the source code distribution archive, and follow the instructions in the file named INSTALL.