It was one of the ealiest form of railway signalling in India. When the visibility of signal is less the aspect of the signal used is repeated to some convenient place. Banner type repeater is used in mechanical signalling territory. One such repeater was workingat PLMD near Coimbatore which was released in the year 1983, when colour light signalling was introduced. This repeater was earlier in duty at Manmadurai section currently plinthed as outdoor exhibit at NMR museum.