I really believe a person would make an entire interesting collection of just logic trainers! we have a couple of the MINIVAC trainers too one I keep under glass and the other I take out for show and tell. We have a fabritek and a few other later ones too. In a message dated 9/23/2015 9:58:30 A.M. US Mountain Standard Time, cube1 at charter.net writes: On 9/23/2015 11:28 AM, couryhouse wrote: There is an earlier one of similar design, but blue colored, in the 1966-67, 1967 and 1968 logic handbooks - so mine is later than that. One with PDP-8/PDP-12 style switches shows up in the back of the 1969 logic handbook. There is one that looks somewhat like mine on the inside front cover of the 1970 logic handbook, and the panels that would be possible to include in one start at page 353. So that dates it to 1970 or after.