HowTo/Scenery/mesh-table/frequency
From TrainzOnline
frequency
This tag is optional.
Date type is number i.e. "1"
This variable specifies the frequency in Hz (or ‘flashes’ per second). e.g. 1 for once per second, 0.5 for once every 2 seconds, 2 for twice per second. If this field is omitted the light will stay on continuously.