Bob Parnass wrote a program called TK-75. It can be downloaded from
http://parnass.com/tk75/ .

If you are using it with Windows, it requires the free tcl/tk program to
work which can be downloaded at
http://prdownloads.sourceforge.net/tcl/tcl832.exe .

I've used it and it's a decent program.


--
Tom Sevart N2UHC
Frontenac, KS
http://www.geocities.com/n2uhc