Transistors
Somewhere I saw an article by Bob Pease (or maybe by someone else at National Semiconductor?) in which he mentions that IC designers at National could go into the lab and find transistors similar to the ones used in National's bipolar process for analog ICs. These TO-5 packaged "kit-parts" could then be used to prototype a new IC design on the bench. Here is an example of one of those prototypes: I've never seen those kind of 8 pin round sockets before, they almost look like miniature tube sockets. picture source (LM168 voltage reference prototype): https://www.electronicdesign.com/technologies/analog/article/21808434/whats-all-this-pease-prototype-stuff-anyhow Unfortunately I am unable to find that article (although I did spend a pleasant afternoon looking on the internet at old Pease articles. The reason for this quest ? It was this announcement made on the IEEE Spectrum page of the MOSbius Project: https://spectrum.ieee.org/mosbius-learning-analog-system-design...