It is easier to read the speed if each LED corresponds to a round number of speed units, although this is not essential.
There are eighteen speed LEDs, so speed scales of 0 - 8.5, 0 - 17, 0 - 34, 0 - 85, 0 - 170 etc. speed units are easier to read.
Suggested speed display ranges for less windy areas are 0 - 34 knots, 0 - 34 mph, 0 - 85 km/hour or 0 - 17 m/s. For other areas 0 - 85 knots, 0 - 85 mph, 0 - 170 km/hour or 0 - 85 m/s may suit.
Modify this zipped .bmp front panel artwork to reflect your choice of speed units and full-scale reading. It is exactly full size if printed dot-for-pixel on a 300 dpi printer. Windows 3.1 Paintbrush allows precise 300 dpi printing on a 300 or 600 dpi printer. The later Paint utility lacks this capability. While Paint is useable for modifying the artwork, IrfanView (freeware) provides more precise control over scaling and printing.
Print a couple of copies of the modified artwork. Check the measurements shown on the artwork with a ruler.
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