VSNCHART.EXE lists and plots chart files downloaded from VSNET, Kyoto University, Japan. VGA and MSDOS5 (or later) are required, and an Epson compatible printer for paper copies from an inbuilt screen-dump. The executable program is called VSNCHART.BIN for download after which it should be renamed VSNCHART.EXE (Your browser may allow you to save it directly with the EXE extension.) A separate subdirectory should be created on the hard disk to hold the program along with chart files. Copy into the subdirectory the three files; 1 VSNCHART.EXE (after renaming) 2 VSNALPH.BIN (do not rename this file) 3 INFO-VSN.TXT (this file) alternatively VSNCHART.ZIP contains all three files. Further chart files should be saved in the subdirectory with unique filenames and the .CHT extension. To run the program (at the DOS prompt) select the subdirectory as default and type VSNCHART followed by ENTER. Operation is largely self-evident with single key presses listed on screen. Starting at the brightest star, filled circles are plotted with a background rim so that all but the closest groups remain clear. Zoom, scroll, and faint magnitude limiting help to optimise the field. X/Y arcminute ticks are based on the SCALE in the file, assumed 0.02 if not present. Selecting 'Plot' gives the option to write a BMP graphics file or do a printout. Note that the program only outputs Epson graphics codes and can produce erratic behaviour on non-compatible printers! However, if the program is installed under a Windows icon, then charts can be transferred to the clipboard with the 'print-screen' key and then pasted into applications such as 'PaintShopPro' or 'LviewPro'. Any windows installed printer will then produce hardcopy. To reduce wear-and-tear on the printer invert the colours for a white background. The re-lettering facility allows scrolling through the set of stars on screen to select comparisons, legends, or neither. On completing a suitable selection, pressing the ENTER key retains the set. Alternatively, pressing ESC will discard all selections. Before finishing with a chart and returning to the list of chart files; If a new comparison set has been retained, then the option to file it is given - replacing any existing set in the file. If a set has been discarded, then the option is given to also remove the filed set, if there is one. Thus putting the CHT file back to its original state. Re-lettering will only operate on the stars that are shown on screen. ie; zooming-in and/or panning vertically/horizontally can place stars outside the rectangle so that they cannot be selected. If the variable itself is faint and a magnitude limit is to be imposed, use re-letter first just to identify the variable with a cross. Then apply the mag limit, and finally re-letter again for comparisons. Re-lettering should be used with care, ideally, observers could aim to use the same set of sequence comparisons. Re-lettered files can be e-mailed to other users of VSNCHART.EXE. The program was originally compiled in November 1995 from MS QuickBasic4.5. An updated version was written in May 1998. Dave McAdam