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2. MECHANICAL MAINTENANCE
The only mechanical adjustment the microscope might require is the tension of the focusing mechanism. This has
been adjusted at the factory, but over the course of time it may loosen and cause the head of the microscope to slip
downward on the focusing block.
The tension adjustment collar is located between arm and focus knob on left side of microscope. With a jeweler’s type
screwdriver, loosen slotted setscrew located on knurled surface of the tension adjustment collar. Turn collar clockwise
to tighten tension, counter-clockwise to loosen tension. After adjusting, tighten the setscrew to lock collar in place.
NOTE: It is recommended that you leave the tension as loose as possible for ease of focusing, yet not so loose that it
permits the head of microscope to drift downward from its own weight and cause the microscope to “drift” out of focus.
3. ELECTRICAL MAINTENANCE
The extent of electrical maintenance, by other than a qualified technician, should be bulb replacement. BE CERTAIN
TO TURN SWITCHES OFF AND REMOVE PLUG FROM POWER SOURCE OUTLET BEFORE CHANGING BULBS.
A. To replace top bulb (factory #800-422 12v 15 watt halogen), remove light shade by rotating in a counter-clockwise
direction. Remove light housing by rotating in a counter-clockwise direction. Remove light bulb by firmly grasping
and pulling straight out from bi-pin socket. Note that this socket holds bulb securely, so you might have to pull
rather firmly. Using a cloth, hold new bulb and gently push new bulb into bi-pin socket. Replace light housing and
light shade.
B. To replace bottom bulb (factory #800-170).... remove cover plate located on bottom of base by removing four
rubber feet that secure cover to base. Holding lamp with a cloth, gently pull lamp straight out from socket. Push
new lamp into place in same manner and replace cover plate.
NOTE: Make certain that new bulb is clean, as fingerprints on bulb can affect light transmission. Grasp bulb gently
with a tissue or cloth to prevent touching bulb surface.
TROUBLESHOOTING:
PROBLEM
REASON FOR PROBLEM
SOLUTION
A light fails to operate.
Outlet inoperative.
Main power switch not turned ON
Have qualified service technician repair outlet.
Push main power switch to ON position
AC power cord not connected.
DC power input not connected.
Plug into outlet.
Plug into adapter and microscope.
Incidental (top light) fails to operate
Incidental switch in OFF position
Lamp burned out.
Push incidental switch to ON
Replace lamp.
Transmitted (bottom light) fails to operate
Transmitted switch in OFF position
Lamp burned out.
Push transmitted switch to ON
position
Replace lamp.
Image only visible in left eyepiece
Camera control rod improperly
positioned.
Push camera control rod completely into head.
Image does not remain in focus
Head of microscope drops from its own
weight.
Adjust tension control collar
Poor resolution
(Image not sharp)
Lens cover dirty
Clean glass surface of lens cover
Spots in field of view.
Eyepiece lens dirty.
Clean eyepiece lenses. ***
***Spots in field of view can also result from dirt on inside of eyepiece. It is recommended that you have service technician clean inside
of lens.