Tube Swap???

Michael Roma

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Can I pull a Kortek KTN-2001 chassis off a Samsung 19" tube (A48kRD89x01) and replace it with a k4900 chassis? The pins on the neckboard match up. Are there any concerns with the yoke?

- Mike
 
Can I pull a Kortek KTN-2001 chassis off a Samsung 19" tube (A48kRD89x01) and replace it with a k4900 chassis? The pins on the neckboard match up. Are there any concerns with the yoke?

- Mike

As I understand it, you can bounce the tube around between chassis and yokes as long as chassis and yoke pairing is not changed. If pins match even better.
 
Mike measure the resistance on the two windings of the yoke. A 4900 is a high impedence board, basically your horizontal deflection is about the same on all of them, it'll be low, like 2.5ohms or lower. that's the blue/red wires. The green/yellow wires will be high on a yoke that works with a 4900. If you measure it and it's 45-60ohms, it'll probably work. If you measure it and it's more like 8-15ohms, it's meant for a low impedence chassis like a K7000 or a K4600.

If the imepedence on either way is off too much, you'll get distorted geometry. For instance if a 4900 likes about 1.3ohms horizontal impedenece, and you put a yoke that has 2.5 impedence, the picture will be smaller, and may have a pincushioned look to it. The vertical is not as critical, since the vertical size adustment is so wide on most monitors, so it'll probably fill the screen but it may have a pincushion look to it. If it's WAY off, the picture will be way too large, and unadjustable. You may even cause damage to your chassis if the yoke is more than 20 or 30% off what it needs to be.

At least that's my experience :)
 
Thanks for the very detailed and helpful response...

After testing the yoke it appears that they do not match and will not work correctly.

Next question, if a tube has the same pinout could I swap a 4900 yoke and chassis on it and then just re-converge it?

- Mike
 
Next question, if a tube has the same pinout could I swap a 4900 yoke and chassis on it and then just re-converge it?

If you use the same convergence rings, mark how they were on the tube, and just swap the yoke it makes convergence a lot less painful. (or so I've heard)
 
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