Long Arm protractor - Bosch DWM40L Miter Finder Digital Protractor/Angle Finder

clock wise is to the right if facing knob.So counter clockwise is turning knob to left and a 180 degrees is half a revolution. Buy a protractor from an office supply store https://www.mathsisfun.com/geometry/protractor-using.html
and turn know to 15 degrees on the protractor.
or use a mobile phone app like https://play.google.com/store/apps/details?id=kr.sira.protractor&hl=en
https://itunes.apple.com/us/app/protractor-1-angle-converter/id331027151?mt=8

'protractor'

Open the the moveable arm and make it straight (180 degrees) or in line with the other.Take the screw off of the black cover at the elbow (1 screw). Lift from the round part and lift off. Then loosen the two screw just inside the cover. This will allow the flywheel to spin and you should now get a read out. If the flywheel does not spin then you need to replace that piece. Gently tighten the two screws and put the cover back on. Hope this helps!

It is a wire that has come off inside the black case

These are the only instructions in the box, the other side of the sheet is a kist of their other products.

INSTRUCTION SHEET
Centering Heads
Curv-O-Mark Centering Heads aid in the setting of centerlines, establishing angles and marks for ****-ins, locating points inside pipes and tanks, laying out keyways and measuring declivity. The standard model (Stock No. 6) is used on pipe 1/2 inch diameter and larger. It has a 4 inch Y-type head and is fitted with an adjustable dial bubble protractor and a manually operated hardened centering pin.
The jumbo centering head (Stock No. 7) is for pipe 1 inch diameter and up. It has an 8 inch Y-type head and an adjustable dial bubble protractor. A spring-loaded hardened centering pin eliminates the need for a hammer.
To quickly and accurately locate the center point on a pipe, shaft or other cylindrical surface, first set the protractor dial at zero (0). Then place the centering head in the vicinity of the highest point of the cylindrical surface.
Move the centering head across the surface until the bubble is centered, then strike the centering pin a light blow. (On the jumbo model, release the spring loaded pin.) The resulting indentation will be top dead center.
If the desired center is at some angle away from top dead center, merely set the protractor dial to the appropriate degree mark to the right or left of zero (0); and then move the centering head around until the bubble is centered. At that point, make the indentation.
The centering pin should be used only in conjunction with the centering head. It should not be used as a center punch. Avoid making unnecessarily hard blows to the pin with a hammer or other objects.
No. 6 Standard Centering Head 0721-0005
No. 7 Jumbo Centering Head 0721-0006
Form 806 R 5-89

Here you go: http://cdn4.grizzly.com/manuals/g9900_m.pdf

Open the the moveable arm and make it straight (180 degrees) or in line with the other.Take the screw off of the black cover at the elbow (1 screw). Lift from the round part and lift off. Then loosen the two screw just inside the cover. This will allow the flywheel to spin and you should now get a read out. If the flywheel does not spin then you need to replace that piece. Gently tighten the two screws and put the cover back on. Hope this helps!

A sliding bevel is used for transferring an angle. What matters is the angle created between the handle and the slider. For example, if you wanted to cut a piece of wood to fit in a corner but that corner is not 90 degrees true. You would loosen the nut, place the center of the bevel in the corner so the edge of the handle lays flat on one wall and the edge of the slider is flat against the other wall. Tighten the screw on the bevel. Now you can lay the bevel on the piece to be cut and mark the exact cut line so the finished piece will fit perfectly.
The sliding T bevel can also be used for setting an angle by using it with a protractor. lay the bevel on a protractor, lock the screw in place at the desired angle, then lay the bevel on the work piece and mark the cut.

Place you protractor over the angle to be measured. Make certain the centre line is aligned with the apes (point) of the angle and one arm (of the angle) is aligned with the protractor's bottom edge. You can now read off the size of the angle by noting the position of the other arm under the protractor's degree scale.

Use a framing square with a set of angle gages (or stops) on it. The protractor can be used but it will take a lot of flipping and changing. The normal settings are 8" rise and 10" tread.