The Model Railroad Chronograph works independent from the scale of the model railroad. The adaptation to the nominal size ensues from different length of the measuring segments: a long section for the high speeds, a short one for the low speeds.

The result of a measuring process will show you the average speed. Therefore, the track sections for the measuring ideally should be plain and straight, without gradients, slopes or sharp turns, so that machines, railcars and trains will go with constant speed.

The watch points at the back– printed from the inside on the sapphire crystal case back – a table with the measuring segments for every nominal size.

Further measuring segments for scales outside the NEM standard:

If there is no possibility for one long and even track in one piece, you can measure off several partial sections. During the drive through the individual sections you can add up the individual times with the start-stop-function (botton A) of the chronograph.
Scale 00 1/4" 7 mm
inch 36 182 61 182 70 352
cm 93 462 154 462 179 894