National 400 Instructions Manual page 4

Objective
Total
Magnification
2X 20X
3X 30X
4X 40X
2X 20X
ILLUMINATION
1. If your model is not supplied with built-in illumination, it should be used where adequate natural or
overhead light is available.
2. If your model is supplied with a port to accept an optional penlight illuminator, you can operate your
microscope without this penlight illuminator, or you may elect to purchase optional #903 penlight
illuminator (requires 2 each AAA batteries, not included).
To install optional #903 penlight illuminator:
a. Remove chrome lamp holder and lamp assembly from body of penlight by rotating lamp holder in
a counter-clockwise direction. Remove white plastic tube from penlight (discard white tube) and
insert 2 each AAA batteries into body of penlight (positive terminals facing up toward lamp).
Replace chrome lamp holder and lamp by screwing tip in a clockwise direction.
b. Insert penlight into black rubber-lined friction mounting port located immediately behind head of
microscope.
3. Determine whether the black or white side of the stage plate will provide best contrast with the
specimen to be viewed. The white side will be used for most viewing. It will always be required when
viewing transparent specimen slides because it better reflects light through specimen slide.
To reverse black/white plate, loosen locking set screw located at front of base with "L" hex wrench
provided. Insert plate with selected surface facing up. Tighten locking set screw.
4. If your model has top (incidental) illumination only, select and position plastic stage plate as described
under "3" above.
5. If your model has both top (incidental) and bottom (transmitted) illumination:
Three switches are on top of base: (1) main power on/off, (2) "I" switch controls incident (top) light,
(3) "T" switch controls transmitted (bottom) light.
This model is furnished with two stage plates.
transparent specimen slides or for viewing some specimen thin enough through which light can pass
(insect wings, etc.). On this model, locking set screw is located on one side of base.
FROSTED GLASS PLATE MUST BE USED IF USING BOTTOM ILLUMINATION.
GENERATED IN BASE FROM BOTTOM LIGHT WILL WARP OR DAMAGE THE PLASTIC
Magnification Chart (illuminated models)
Eyepiece
WF10X
(supplied)
Field
Size Magnification
10mm
6.7mm
5mm
Magnification Chart (non-illuminated models)
10mm
WF15X
(optional)
Total Field
Size
30X 6.5mm
45X 4.3mm
60X 3.3mm
30X 6.5mm
The frosted glass plate is used when viewing
4
Maximum
Working Specimen
Distance Height
65mm 58mm
55mm 60mm
40mm 60mm
75mm 57mm
HEAT