The Lectron Trainer 1102 – NPN combined the 1100 and 1101 models into a more comprehensive curriculum that covered the Electronics I and II courses of study.

The NPN model featured two NPN transistors (the legacy Lectron System models exclusively used PNP transistors).  The reader will note the change in battery block style to allow either the plus or negative polarity to be grounded depending upon the type of transistor being used.