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6
MAINTENANCE
WARNING: For your own safety, turn switch off and remove plug from power source before
maintaining your microscope. If the power cord is worn, cut or damaged in any way, have it
replaced immediately to avoid shock or fire hazard.
OPTICAL MAINTENANCE
1. Do not attempt to disassemble any lens components. Consult a microscope service technician when
any repairs not covered by instructions are needed.
2. Prior to cleaning any lens surface, brush dust or lint off lens surface using a camel hair brush. You
can also use an ear syringe or canned compressed air, such as that sold by most computer stores.
3. To clean eyepiece lenses, do not remove from eyepiece tube. Clean only the outer lens surface.
Breath on lens to dampen surface, then wipe with lens paper or tissue. Avoid wiping dry lens surface
as lenses are scratched easily. If excessive dirt or grease gets on lens surface, a small amount of
Windex can be used on a cotton swab or lens tissue. To clean objective lenses, do not remove
objectives from microscope. Clean front lens element only, following same procedure.
MECHANICAL MAINTENANCE
The only mechanical adjustment you might ever 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.
To adjust, observe that stem of focus knob on one side of microscope has a tension adjustment collar
with four small holes. Only one of these holes contains a small set screw. Using a small jewelers
screwdriver, loosen this set screw. Your microscope was supplied with a small pin spanner wrench
having one prong. Insert pin of the wrench into one of the holes, turn collar clockwise to tighten tension,
counter-clockwise to loosen tension. In the event you have misplaced the wrench, a large rubberband
placed around the collar will permit you to grip the collar and turn it by hand in order to accomplish the
same adjustment. After adjusting, tighten the small set screw 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.
To clean metal parts, use a clean, damp cloth to remove dust or dirt from surfaces. Then, completely dry
surfaces with a dry cloth.
ELECTRICAL MAINTENANCE
WARNING: For your safety, turn switch off and remove plug from power source before
maintaining your microscope. Wiring and transformer contained in base of illuminated models
should be repaired only by qualified technicians.
1. To replace top light (TL & TBL models only), you will require National part #800-400, 12v 10 watt
tubular bulb, or bulb of exact same specifications from other microscope manufacturers.
Remove knurled lamp retaining screw, located on side of top lamp cover, and remove cover from
lamp. Remove lamp from pressure clips by pulling straight out. Holding new lamp with tissue or cloth
to avoid getting body oil on lamp, push into pressure clips. Replace lamp cover and secure with
knurled lamp retaining screw.