5-4-260 (Key) Sender
In automatic telephony, a device which accepts and stores groups of coded pulses and which thereafter controls the setting up of a call. For a key sender, the pulses are produced by the depression of digit keys.
Reference: B.S. (modified)
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)
Centre of buoyancy
International Association of Marine Aids to Navigation and Lighthouse Authorities - AISM