Mainline Model Railways
Electronic Sound Modules
Introduced in 1980 were the Steam Sound module fitted locomotives, in the two Royal Scot Sets. This module produced steam engine sounds and was powered by a battery in the Tender.
The two later modules introduced in 1981 were for Diesel and Steam Locomotives and produced not only Locomotive sounds but Whistle and Klaxon noises triggered by a ramp in the track. They picked up their power from the track, no battery was needed.