This Identification Guide for Lionel Electric Trains covers the "Post-war Era" only from 1945 until 1969.
LIONEL TRAINS TRANSFORMER TYPE 1035
The Lionel 1035 Transformer was available only in 1947. It generated 60 Watts of power and would control one train. It does not have a built-in circuit breaker nor did it come with a horn/whistle circuit. There are no variations.