Pertec 9-track Formatter "Key To Tape" device

This device is NOT part of the Entrex 480 system, 

but in order to understand a "Key-To-Disk" system like the Entrex 480, 

here is a "Key-To-Tape" stand-alone device to illustrate the differences.  

Notice the "029" keyboard layout?

Acquired from Orrill's Auctions, Los Angeles on March 12, 2024

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And ANOTHER one from March 28, 2024!

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And HERE'S one found on reddit from January 10, 2023

Posted by u/[deleted] of course, so we'll never knew where it came from

PS: In our opinion, there was no need to take the cover off the core memory and risk damage or contamination, but I guess the owner of this system was curious, so here it is.  

Apparently, reddit commenter u/the123king-reddit also had this concern.

UPDATE:  Schematics from Jon Elson  

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The Video Display Module (VDM-1)

Isn't this made from the base of one of the above??  

https://images.computerhistory.org/timeline/timeline_computers_1975.vdm.jpg

Designed by computer pioneer Lee Felsenstein, the Video Display Module (VDM-1) marks the earliest implementation of a memory-mapped alphanumeric video display for personal computers. Introduced at the Altair Convention in Albuquerque in March 1976, it was a much-needed input device for hobbyists building their own microcomputer systems at the time and became the basis of the SOL-20 computer.