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Help adjusting monitor with slanted image

It looks as if the deflection yoke assembly has shifted during shipment. Simply rotate it back into position. There is a clamp that holds the yoke to the CRT neck; you may need to loosen the clamping bolt somewhat so it's free to move.

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Thank you, Chuck. I'm going to let the capacitors discharge and check it tomorrow!
 
May I suggest that safety glasses be worn, just in case.

You must be be one hell of a klutz! <grin>

Yes, the CRT is under high vacuum. If it breaks, it's going to *implode*, not explode - and although it is theoretically possible to still have flying glass, I've never seen it happen. Modern tubes all have implosion protection bands, so the worst you'll get is a loud *FFFSHHH!* and some cursing once you realize you broke the tube.

The neck is the most fragile point of the tube, and a sharp blow will break it. But adjusting the yoke is simple and safe - just be sure not to touch the HV anode while you're in there. Just rotate the yoke by it's plastic housing until the picture is level, and snug it back down - there is a screw clamp at the back of the yoke. You don't want to overtighten this, for the above "breaking glass" reasons, just snug it down so the yoke won't move easily.

The usual warnings apply when working around high voltage, but you should not have any problems - you don't have to mess with any of the HV components to just adjust the yoke position.

-Ian
 
You must be be one hell of a klutz! <grin>

Yes, the CRT is under high vacuum. If it breaks, it's going to *implode*, not explode - and although it is theoretically possible to still have flying glass, I've never seen it happen. Modern tubes all have implosion protection bands, so the worst you'll get is a loud *FFFSHHH!* and some cursing once you realize you broke the tube.

The neck is the most fragile point of the tube, and a sharp blow will break it. But adjusting the yoke is simple and safe - just be sure not to touch the HV anode while you're in there. Just rotate the yoke by it's plastic housing until the picture is level, and snug it back down - there is a screw clamp at the back of the yoke. You don't want to overtighten this, for the above "breaking glass" reasons, just snug it down so the yoke won't move easily.

The usual warnings apply when working around high voltage, but you should not have any problems - you don't have to mess with any of the HV components to just adjust the yoke position.

-Ian

Implosion will still cause a lot of acceleration, even though it's towards the centre of the tube. When a fragment is accelerated and reaches the centre, it's velocity doesn't just dissapear, and it is very likely that it will keep flying out on the other side, with potentially dangerous momentum (assuming the whole neck/tube breaks to fragments).
 
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Wear rubber-soled shoes; if you're touching live circuitry (i.e. with the power on), keep one hand in a back pocket. Positively ancient safety rules. You may get "bit", but you won't get hurt or killed. If you work on high-current (not necessarily high voltage) circuitry, remove any metal jewelry from your hands--a hundred amps flowing through a ring gets awfully hot.

In other words, use common sense and pay attention to what you're doing. The high voltages used on the anode of a CRT are very low current. If you're really paranoid, this is an adjustment that can be done with gloves on.

Most of the time, when small CRTs are broken, you hear a hiss and that''s it. Old 1950s-60s TVs often used CRTs without a laminated-on shield and they're really the dangerous ones.
 
Thank you for all the advice. I successfully placed the deflection yoke in its correct place. Now the image is centered and the colors are aligned.


Click to enlarge
 
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