> On May 2, 2016, at 3:59 PM, Mattis Lind <[email protected]> wrote:
> 
> Yet another nice color brochure.
> 
> https://dl.dropboxusercontent.com/u/96935524/Datormusuem/lab11.pdf
> 
> Has anyone seen a VR20 in real? Rather interesting to be able to do a red
> and green X/Y screen based on different energy levels. Someone care to
> explain how that works?

See https://en.wikipedia.org/wiki/Penetron.  The idea is that there are two 
layers, and a high voltage beam pokes through the first to activate the second.

I think Tektronix made monitors of this type, but apparently GE invented them.  
I remember hearing about that technology in the 1970s; I never actually saw one 
in the wild (from any manufacturer).

> If I read the fine print on the back correctly (and comparing with the
> others) I would guess that this brochure is from 1971.

Assuming that 00771 is a date code, yes.  The cover photo is interesting (PDP11 
with PDP12 color scheme!) but the console looks like an LA30.  I didn't know 
those were out in 1971.  The first (and fortunately only) one I encountered was 
in 1974.

        paul

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