WG K4500 worth saving?

Zork2

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Thoughts......
I have a WG K4500 out of an early model Galaxian......
This thing looks ARCHAIC as HELL!!
It has a picture, but is really REALLY dim.....
Is a K4500 even worth saving? Or should I shit can this thing and just put one of my spare G07s in its place?
I don't get a warm fuzzy when looking at it.......
 
They are a nasty beast. Ive rejuvenated a few of the tubes to bring it back to life. If you can get it to work....might as well use it until it's dead.

Edward
 
4500 can be a great monitor. They're a lot different than the newer monitors like the G07, but despite being so old, it's definitely possible to get a good picture out of one.

For one, the K4500 uses a delta gun picture tube. This is different than the inline gun tubes used in newer monitors because the arrangement of the phosphor dots and electron guns is different. The process of converging it is also much different - delta gun tubes use an electronic convergence setup - that's the large board with all the knobs mounted to the yoke.

I'd be inclined to fix it up, I really rather like these monitors. They can be very reliable. The tubes are also fairly long lived.

Have you tried cleaning the face of the tube? Half the 4500's I see are so filthy they just look really dim...

-Ian
 
4500 can be a great monitor. They're a lot different than the newer monitors like the G07, but despite being so old, it's definitely possible to get a good picture out of one.

For one, the K4500 uses a delta gun picture tube. This is different than the inline gun tubes used in newer monitors because the arrangement of the phosphor dots and electron guns is different. The process of converging it is also much different - delta gun tubes use an electronic convergence setup - that's the large board with all the knobs mounted to the yoke.

I'd be inclined to fix it up, I really rather like these monitors. They can be very reliable. The tubes are also fairly long lived.

Have you tried cleaning the face of the tube? Half the 4500's I see are so filthy they just look really dim...

-Ian

I don't remember the details.....but the first one my friend rejuvenated.....I remember him going through the setup......multiple times, babbling....this is freaking weird!

Edward
 
I don't remember the details.....but the first one my friend rejuvenated.....I remember him going through the setup......multiple times, babbling....this is freaking weird!

Hehe. It is weird, if all you've ever worked on are modern inline gun sets.

Old tubes had three separate gun assemblies, and they're arranged in a triangle. You have to start with the purity, of course - that gets slightly different because there's a separate magnet assembly just for the blue. But then you do the static convergence setup, by adjusting the magnet assembly similar to the convergence on an inline tube. You use the static controls to adjust just the center of the screen, for the most part. Then you use the dynamic convergence controls (the electronic ones) to get the edges and the corners. I find converging a delta gun set to be a little easier, because you don't have to keep fiddling with the yoke position as much...

Properly adjusted, a delta gun tube can look fantastic. All older television sets are like this, it wasn't until the late 70's that inline gun sets started to appear (the first on the market that I am aware of is the Trinitron). Other sets followed suit, as inline sets are generally cheaper to make.

The K4500 is not the only delta gun arcade monitor. The Electrohome G02 is also delta gun. I don't know of any others. Those two were the first color arcade monitors, although I believe the G02 was the first. It was used in early 25" Galaxians. Later 19" Galaxians were K4500's.

-Ian
 
I doubt its a film on the screen, it is a REALLY dim picture, as in almost not even visible. I've tried just about every pot in the back (and there are a TON!) with no luck, I can't even get any of them to do anything.
Maybe I'll try a rejuv on it and see what happens.
Other than a cap kit, I really don't see many parts out there for these?
I'd really rather not spend a bunch of time and money on it, only for it to be a giant pain in the A$$!!
 
I doubt its a film on the screen, it is a REALLY dim picture, as in almost not even visible. I've tried just about every pot in the back (and there are a TON!) with no luck, I can't even get any of them to do anything.
Maybe I'll try a rejuv on it and see what happens.
Other than a cap kit, I really don't see many parts out there for these?
I'd really rather not spend a bunch of time and money on it, only for it to be a giant pain in the A$$!!

If it's working and just dim then it's at least worth trying a cap kit and a rejuv. Worst case, you've wasted an hour and a few bucks.
What happens when you crank up the Screen control on the flyback?
 
If it's working and just dim then it's at least worth trying a cap kit and a rejuv. Worst case, you've wasted an hour and a few bucks.
What happens when you crank up the Screen control on the flyback?
Well it really only has one adjustment on the fly, it does nothing.....
There is a "brightness" pot that does nothing either.....
 
Well it really only has one adjustment on the fly, it does nothing.....
There is a "brightness" pot that does nothing either.....

Yeah, the one big long pot on there is the Focus. IIRC, this beast actually has 3 separate Screen controls. Should be located near the flyback.
 
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