My premiere microscope MS-01 Ultra will not focus

All LED microscopes use a 5v power supply

Since there's only a very small amount of light reaching the lens system of microscopes when on high powers, A special technique (called >>>oil immersion
Not using this technique must be the cause of the problem you are experiencing.
eHow will guide you through the exact procedure of using the oil immersion technique: http://www.ehow.com/how_8431358_focus-high-power-objective-microscope.html
Good luck in exploring the micro world!

There is probably oil on the outside of the object. You can try cleaning it off with some alcohol and a que-tip. If that doesn't work, the seal of the objective has probably failed and oil has seeped up inside. Otherwise the other problem that can cause it is to many small scratches to the outer lens of the objective. This can happen when the objective lens crashes through a slide.

One thing you can do to protect your objective from this happening, is that most microscopes have some sort of up stop lock, which is designed to prevent the stage from coming past a certain point. On your model, this is most likely a screw that sits just behind the stage.

If the cleaning doesn't work, the usually replacing it is the most economical option. This model has a pretty standard object type, so any object that has a 160mm tube length and has standard RMS threading should work with it just fine.

Just inside the coarse focus knob you will see a "chrome" ring with holes it it. That ring needs to be tightened just a bit. It will make the coarse focus knob stiffer so tighten only enough to stop the downward drift of the stage. A funny looking tool should have come with the scope. It is used to adjust this "tension" ring.

The knob you are talking about is called the x-axis control knob. It does not directly affect the focus. What affects the focus is the slight manipulation of the stage and or slide while you are adjusting the x-axis control knob. It only takes the slightest pressure to throw the focus off very far. Theoretically you could completely remove the specimen holder and move the slide around with your fingers.
The specimen holder may need to be replaced but without further more detailed knowledge of the mechanical problem I cannot instruct further.

There are two reasons. One reason is that when on high power you are working so close to the glass slide that it is easy to misjudge how much you are moving the specimen toward the lens that you can break a slide before you realize it. The coarse focus moves the stage with the specimen on it very fast and you only have a very very short distance within the focus plane before you run the objective lens into the slide.
Secondly, it is just harder to control the minute adjustments needed at the higher powers with the "coarse" focus knob. If you start at the low magnifications find what you want to concentrate on with the coarse focus knobs and then work your way up to the higher powers, you will have very little trouble moving to the fine focus controls at 40x and 100x while still having control of your image.

Check out the following link....
http://www.hometrainingtools.com/how-to-use-a-microscope/a/1120/

First, a scope of this grade will not be completely in focus as you move from one magnification to the next. But it should be close enough that you do not loose your point of interest.
Be sure you are not pressing down on the stage specimen platform as you change magnifications. It is very sensitive to pressure. Also, be sure that the coarse focus tension is tight enough that the platform is not drifting down imperceptibly as switch magnifications. Look through the scope and watch if the image goes out of focus while you are watching it. If so, you have what is called "stage drift". This is corrected by tightening the tension on the coarse focus knob.
The tension adjustment is on the coase focus shaft. It looks like a chrome ring with about 3 holes in it. There should have been a strange looking tool that came with your scope. It is used to adjust the tension. If your specimen is "drifting" out of focus, simply tighten the tension ring a little bit at a time until the specimen no longer goes out of focus. Do not get it so tight that it is not easy to operate the coarse focus knob.

This might be sign of trouble, because the Nylon gears inside might be worn out. I did not noticed a tension ring on Optiphot 1 or 2. The Nikon S and Metaphot from 1960s to 1976 have Nylon gears with tension ring adjustments.

sir,
Diffrent company having their own system for microscope arm balacing.

Tell me which one microscope you have.

Auxillary arm or microscpe body sloly come down ward.

tell me problem is consult with which part..

INDRAVIJAY