Can't identify this type monitor. Can it even be rebuilt?

[modessitt]

This is from a Computer Space game, the first arcade commercially released, circa 1971.

It uses a 13" black and white General Electric TV with VACUUM TUBES on the chassis.     But that's all the info I could find out - no chassis type or anything.

I felt lucky that the monitor was working and had a picture, but found out that the picture started screwing up after being on for a couple hours.

Should I even bother trying to fix this monitor, or should I try to figure out something else to use as a replacement?  What would even be a replacement?  If this IS a TV, then would an arcade monitor even work?   

Anyone ever messed with one of these?  There are schematics for the TV in the paperwork, but would parts even be available anymore?

[Ken Layton]

In the old days game manufacturers took regular tv sets and stripped out the tuners. They tapped into the video input and fed the monitor standard NTSC composite video.

If you have a tv set, or VCR with a video input jack you can feed the video from the gameboard to your own tv set.

[modessitt]

Thanks for the reply, Ken....

But to keep it original, it would have to be b&w.  Guess I should hit the thrift shops and look for a working 13" b&w TV that I can decase and try to plug in.  Any resources available for stripping out tuners and wiring in an NTSC signal?  Doubt it would be the same as on the GE TV as it uses vacuum tubes in its circuitry.  I don't usually work with TVs and don't know about trying to convert the signal from this old board to a connector that would plug into a VCR, although it's an interesting idea.

BTW... What would the picture look like if I tried to display it on a color TV?  Would it show in b&w?  I'm thinking that the "white" signal would have to be plugged into one of the RGB inputs and would show in that color?

[StephenH]

You might want to ask on http://www.audiokarma.org forums, as there is one that deals with antique TVs there.   They might know what to do.


You need to determine if the signal into it is composite or "White" level.  If it is composite, you can connect it to the "Video In" of a TV.   if it is a "White Level", you need to determine its voltage level, and if it is the same, you might be able to use a color monitor if you connect the signal to all three colors.  This is how color monitors achieve the "Grey Scale".  White is achieved by Red, Green, and Blue at full blast.

[paigeoliver]

You can also still get a lot of various TV tubes. There is an electronics place in my town that has them packed in to a shelving unit 6 feet high floor to ceiling. A computer space is a really high value game, it would be better to keep the original display if you can repair it. See if you can find out if there is a tube tester somewhere in your town that you can use. TV repair shops that have been there a long time may still have one, failing that, you can probably locate an antique TV collector locally that has one. Actually just finding an antique TV collector first is probably your better bet, as they might just be willing to repair the thing for you for nothing or close to nothing.

[modessitt]

Tube tester......hmmm......  You know, I think we have one on the shelves somewhere from back when we did a lot of old jukebox repair.

In the meantime, I'll see what I can do about finding someone local who has experience dealing with these things. 

Unfortunately, the customer had me take it out and set it up in his "electronic museum" lobby even though the picture goes unstable after a few hours of use.  They're leaving it unplugged until they want to show it to someone.  As you can imagine, in a building full of game programmers, it garners a lot of attention.  Only problem is I can't really experiment with testing the video signal and such until he lets me bring it back to the shop.

[Ken Layton]

Those particular tv sets from that ere used "Compactron" tubes (a G.E. trademark). Those are multisection tubes that do several functions at once. They fail alot, but at least they are cheap to buy nowadays. Get them at www.tubesandmore.com

I'd retube the whole thing first.

[modessitt]

I'll let the customer know about that option.

Thanks, Ken!