Vacuum Tube Etch-A-Sketch

Comments and faves

1. ★

   xtoq, jfk_fin, Fabrice Terrasson, Moogulator, and 31 other people added this photo to their favorites.

2. 

   ranjit (71 months ago | reply)

   ooh, shiny shiny gadgets!

   how does it work??

3. 

   AMagill (71 months ago | reply)

   Ooooooohhhh...

   On another note, I've always wondered.. how the heck did storage o-scopes work before we had solid state storage?

4. 

   jurvetson (71 months ago | reply)

   I was wondering the exact same thing. Here's a piece of vintage electronics with a screen and a handful of vacuum tubes. No transistors or memory chips. So how does it "remember" the trace on the screen to show it persistently? From a bitmap perspective on the screen, there is a lot of data to be retained...

   The answer is fascinating. Memory is implemented in the display screen itself with a separate tracing beam reading the phosphors and regenerating them with the write beam (Wikipedia details). It reminds me of early computer memory systems that stored data on the phosphor of a CRT…. (giving “Video RAM” a literal instantiation =)

   Ranjit: so now that we know how an image can stay on screen, to make an Etch-a-Sketch, you dial the beam down to a point or small bar, and use the vertical and horizontal adjustment knobs to paint with light. It has all the limitations of the original toy (you can’t lift the “pen”) but it does have half-screen erase options…

   This is an alpha-stage product, so the flicker on the screen is missing a couple letters. Today, flickr is in gamma, so it's just missing one letter.... ;-)

5. 

   TheAlieness GiselaGiardino²³ (71 months ago | reply)

   oh, so it did mean to say "flickr" there?! I thought it was pareidolia...

   the commands below the screen must have influenced me too -i thought-... those buttons... so flickristic.

6. 

   Telstar Logistics (71 months ago | reply)

   Love this. The perisistence thing is very pronounced on my new old HP o-scope as well. Tracers!

7. 

   Mo, In The 415 (71 months ago | reply)

   ...Or Something! I can't wait to show this to a few friends who are always in search of the newer/smaller/faster electronic thing-a-ma-bob. Can't wait for the *cringe*.

8. 

   See you @ http://www.ipernity.com/doc/ypell ypell [deleted] (69 months ago | reply)

   Oh, fun!

9. 

   Omsel (69 months ago | reply)

   You're invited to post this image to Red or Yellow or Green Group

10. 

    lilith penguin (69 months ago | reply)

    Geek heaven!

    --
    Seen in Scientist Photographers (?)

11. 

    bailingdirt (55 months ago | reply)

    Hi, I'm an admin for a group called Measuring Devices, and we'd love to have your photo added to the group.

12. 

    realblades (54 months ago | reply)

    Wow

13. 

    DodogoeSLR (52 months ago | reply)

    very cool

    1-2-3

14. 

    Another Partial Success (52 months ago | reply)

    Lordy - been a while since I've seem of those bits of kit.

    Great fun and a trip down memory lane!

    I found this photo in 1-2-3

    jon

15. 

    nudeguitardude [deleted] (29 months ago | reply)

    [http://www.flickr.com/photos/nudegdude/42068 30689/]

    Hi, I'm an admin for Mancave, a group for Men's Secret Lairs.

    We'd love to have this added to the group!

16. 

    k7pmi (7 months ago | reply)

    Great photo! Please add to Group:
    www.flickr.com/groups/86846338@N00/pool/with/ 6292914280/

17. 

    Astrocatou (3 months ago | reply)

    Cool....

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