Collection of pages from K&E catalogs for the DeciLon Demonstration Slide Rule
Catalog page from the 1962 catalog
K&E produced large demonstration versions of several of the most popular models. K&E model 68 1929 is a 6 foot version of the DeciLon. It was intended to hang on a wall or frame for use in classrooms.
The model 68 1929 was first shown in the 1962 catalog. The following is a brief history of the N105 family of slide rules as is told in the K&E catalogs that are available at this time. Exact timing is not possible because of the time between catalogs.