seven segment display history

[Brent Hilpert]

Jules Richardson wrote:
> 
> Brent Hilpert wrote:
> > The earliest *off-the-shelf* 7-segment display modules that I've run across are
> > from ca. 1967:
> >   http://www3.telus.net/~bhilpert/tmp/dialco7seg/
> > As can be seen, they use neon bulbs. The displays themselves are not dated but
> > other component date codes in the instrument they came out of were in the range
> > 66xx-67xx.
> 
> Now that looks like the sort of thing I saw in the mock-up (unfortunately
> there's a lot of reflection in the photo that I took from the perspex screen
> they'd covered the model with, so it's probably not worth sharing).
> 
> It's impossible to tell from the mock-up exactly what type of technology it
> was though; it was just the seven-segment nature that surprised me, as I don't
> think I've seen it that early elsewhere (everything was either Nixie or stacks
> of side-lit perspex plates with proper formed numerals on them).
> 
> Interesting point from Chuck about the possible failure mode of 7-seg's
> though. Perhaps they never thought of that!

(.. just reminds me the 'LAMP TEST' button used to be a standard feature on
control consoles, in general; and the 7447 7-seg decoder has a lamp-test input.)

Don't know if it correlates with the sort of equipment you saw, but I agree
with Chuck the mission control consoles in the pic he provided look like
film-projection displays, the numerals are too well-formed. I have one
frequency counter using that type of display.