Unitron System 374 User manual

73 Mall Drive, Commack, NY 11725 • 631-543-2000 (P) • 631-589-6975 (F)
www.unitronusa.com • [e-mail]
System 374
ZOOM STEREO
MICROSCOPE
MANUAL

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 2
CONTENTS
SAFETY NOTES .................................................................................................................. 3
CARE AND MAINTENANCE ................................................................................................ 3
INTRODUCTION .................................................................................................................. 4
UNPACKING AND COMPONENTS ..................................................................................... 4
COMPONENT DIAGRAMS ............................................................................................... 4-5
ASSEMBLY .......................................................................................................................... 6
ASSEMBLING THE BALL BEARING BOOM STAND ..................................................... 6
ASSEMBLING THE PLAIN STAND ................................................................................ 9
INSTALLING THE BEAM SPLITTER ............................................................................ 11
ASSEMBLING THE BEAM SPLITTER, VIEWING HEAD & CAMERAS ....................... 11
ADJUSTMENT AND OPERATION
ADJUSTING BINOCULAR VIEWING HEAD................................................................. 13
FOCUS ADJUSTMENT................................................................................................. 14
SPECIFICATIONS.............................................................................................................. 15
TROUBLESHOOTING........................................................................................................ 16
MAINTENANCE.................................................................................................................. 17
SERVICE ............................................................................................................................ 17
WARRANTY ....................................................................................................................... 17

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 3
SAFETY NOTES
1. Open the shipping carton carefully to prevent any accessory, i.e. objectives or eyepieces, from
dropping and being damaged.
2. Keep the instrument out of direct sunlight, high temperature or humidity, and dusty environments.
3. If any specimen solutions or other liquids splash onto the stage, objective or any other component,
disconnect the power cord immediately and wipe up the spillage. Otherwise, the instrument may be
damaged.
4. LAMP REPLACEMENT -- CAUTION: the glass housing of the lamp may be extremely
hot. DO NOT attempt to change the lamp before it is completely cooled or without
wearing adequate skin protection.
5. All electrical connectors (power cord) should be inserted into an electrical surge protector to prevent
damage due to voltage fluctuations.
6. FUSE REPLACEMENT -- For safety when replacing the fuse (ONLY replace with the
same size, type and rating of original fuse), be sure the main switch is in the off position,
disconnect the power cord from outlet, and replace the fuse. Reconnect the power cord
and turn unit on.
7. Confirm that the input voltage indicated on your microscope corresponds to your line voltage. The
use of a different input voltage other than indicated will cause severe damage to the microscope.
NOTE: Always plug the microscope power cord into a suitable grounded electrical outlet.
A grounded 3-wire cord is provided.
CARE AND MAINTENANCE
1. Do not attempt to disassemble any component including eyepieces, objectives or the focusing
assembly.
2. Keep the instrument clean; remove dirt and debris regularly. Accumulated dirt on metal surfaces
should be cleaned with a damp cloth. More persistent dirt should be removed using a mild soap
solution. Do not use organic solvents for cleansing.
3. The outer surface of the optics should be inspected and cleaned periodically using an air bulb. If dirt
remains on the optical surface, use a soft, lint free cloth or cotton swab dampened with a lens
cleaning solution (available at camera stores). All optical lenses should be swabbed using a circular
motion. A small amount of absorbent cotton wound on the end of a tapered stick makes a useful tool
for cleaning recessed optical surfaces. Avoid using an excessive amount of solvents as this may
cause problems with optical coatings or cemented optics or the flowing solvent may pick up grease
making cleaning more difficult.
4. Store the instrument in a cool, dry environment. Cover the microscope with the dust cover when not
in use.
5. UNITRON®microscopes are precision instruments which require periodic servicing to maintain
proper performance and to compensate for normal wear. A regular schedule of preventative
maintenance by qualified service personnel is highly recommended. Your authorized UNITRON®
distributor can arrange for this service.

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 4
INTRODUCTION
Congratulations on the purchase of your new UNITRON®microscope. UNITRON®microscopes are
engineered and manufactured to the highest quality standards. Your microscope will last a lifetime if
used and maintained properly. UNITRON®microscopes are carefully assembled, inspected and tested
by our staff of trained technicians in our New York facility. Careful quality control procedures ensure each
microscope is of the highest quality prior to shipment.
UNPACKING AND COMPONENTS
Your microscope arrived packed in a molded shipping carton. Do not discard the carton: the shipping
carton should be retained for reshipment of your microscope if needed. Avoid placing the microscope in
dusty surroundings or in high temperature or humid areas as mold and mildew can form. Carefully
remove the microscope from the shipping carton and place the microscope on a flat, vibration-free
surface.
COMPONENTS DIAGRAM
Ergonomic
Binocular Head
Eyepieces
Zoom Body
Ring Light
Focus Mount
Vertical Post
Horizontal Pillar
Base
Ball Bearing
Boom Stand
Focus Knob
Ring Light
Controller
Excelis HD Camera
Beam Splitter
Video Adapter

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 5
Ergonomic
Binocular Head
Eyepieces
Zoom Body
Lens/Objective
Focus Mount
Focus Knob
Ring Light
Plain Stand
Ring Light Controller
Excelis HD Camera
Beam Splitter
Video Adapter

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 6
ASSEMBLY
The following photos show how to assemble the various modules in the order of assembly.
When assembling the microscope, make sure that all parts are free of dust and dirt, and avoid scratching
any parts or touching glass surfaces.
Assembling the Ball Bearing Boom Stand
1. Carefully remove all parts from box and
check for all package contents.
2. Place the base on the edge of a table as
shown below. Use the hex bolt to attach
the vertical post to the base, and tighten
using the hex wrench provided.

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 7
3. Place the base on the table and unscrew
the cap on the vertical post.
4. Insert the safety lock collar onto the
vertical post and tighten/lock it using the
clamp.
5. Slide the horizontal pillar with cross block
into the vertical post.
6. Adjust to the desired position and tighten
the cross block on both sides using the 2
knobs.

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 8
7. Replace the cap back onto the vertical
post.
8. Screw the lock lever on the end of the
horizontal pillar. This lock lever secures
the e-arm or focus mount.
9. Insert the e-arm or focus mount into the
end of the horizontal bar and tighten
using the lock lever.
10.Adjust the e-arm or focus mount to
desired level or position.

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 9
11.E-arm or focus mount can be inserted
from the TOP, BOTTOM or
HORIZONTALLY of the horizontal bar.
Set e-arm or focus mount up at various
angles and tighten the lock lever for
oblique viewing.
Ball Bearing Boom Stand assembly is complete.
Assembling the Plain Stand
1. Set the stand flat on a work surface.
Insert the stage plate into the stand base.

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 10
2. Install the focus arm. Align the focus arm on
the focus mount of the pillar as shown. Using
the supplied hex key, attach the focus arm to
the focus mount with the supplied hex
screws.
Plain Stand assembly is complete.
Mounting the Zoom Body
1. Carefully place the zoom body into the focus
mount and tighten the lock screw to secure
the zoom body in place.
2. Use caution not to over tighten the locking
screw as this may cause damage to the
instrument.
Mounting the Objective
1. Using care not to touch the lens surfaces,
carefully thread the objective into the optical
body.

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 11
Installing the Beam Splitter
1. Place the beam splitter onto the top of
the optical body by matching the groove
of the of the beam splitter’s bottom and
the securing screw of the optical body.
Tighten the screw to secure the optical
body and the beam splitter. Install the
viewing head on top of the beam splitter
and secure it with Allen screw.
Beam Splitter Assembly
1. Insert the viewing head

into the beam
splitter and secure it into place using a
2mm Allen key to tighten the screw.
2. Insert the standard connecting tube 
into the beam splitter and secure it into
place using a 2mm Allen key to tighten
the set screw.
3. Remove the rubber plug inserted into the
C-mount on the bottom of the Excelis
camera revealing the threads. Be
careful not to touch the glass in the
bottom of the camera.
4. Thread the video adapter into the C-
mount on the bottom of the camera.
5. Insert the video adapter into the standard
connecting tube and secure into place
using a 2mm Allen key to tighten the set
screw.

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 12
Installing the Eyepieces
1. Remove the dust caps from the eyepiece
tubes.
2. Insert the eyepieces into the eyepiece
tube. Be sure to install the eyepieces all
the way into the tube.
3. Set the eyepiece diopter scale for each
eyepiece to 0.
Attaching the Ring Light
4. Remove the dust caps from the eyepiece
tubes.
5. Insert the eyepieces into the eyepiece
tube. Be sure to install the eyepieces all
the way into the tube.
6. Set the eyepiece diopter scale for each
eyepiece to 0.

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 13
ADJUSTMENT AND OPERATION
Adjusting Binocular Viewing Head
Adjusting Interpupillary Distance (Fig. 6)
Different users have different interpupillary
distances (this distance is between the centers
of the pupils of each eye). When the operator of
the microscope changes, it will be necessary to
adjust the interpupillary distance.
While looking through the eyepieces, hold the
left and right eyetubes of the viewing head and
adjust the eyetubes by opening or closing them
until the left and right fields of view coincide
completely and you are able to see a complete
circle.
Adjusting Diopter Ring/Focusing (Fig. 7)
Set the diopter rings ②of both eyepieces to “0”
position. (Do this when users change, because
different users will have different diopter
settings.)
Place an easy-to-observe specimen on the
stage plate, i.e., a coin.
Rotate the zoom knob ③to the highest
magnification, and turn the focusing knob ④to
focus the specimen.
Rotate the zoom knob ③to the lowest
magnification, looking only into the left eyepiece,
adjust the diopter ring on left eyepiece to focus
the specimen. Then repeat this procedure for
the right eyepiece.
NOTE: The working distance (the distance
between the microscope objective to the top of
the specimen) of the microscope is 186mm (with
0.5X objective, included).
Fig. 6
Fig. 7
②
③
④

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 14
Focus Adjustment
Adjusting the Rotation Tension of the
Focus Adjustment Knob (Fig. 8, Fig. 9)
To adjust tension, hold both left and right focus
adjustment knobs ①with both hands, hold the
left knob (to prevent it from turning), and rotate
the right knob clockwise to increase (tighten) or
counterclockwise to decrease (loosen) the focus
knob tension.
After tension adjustment has been completed,
always rotate both adjustment knobs in the
same direction.
Changing the Magnification
The zooming knobs located on both sides of the
zooming body will change the magnification of
the specimen image.
Total Magnification = Magnification of zoom
body x objective x magnification of eyepiece
(i.e., 0.8 x 1.0 x 10 = 8X)
Moving the Microscope (Fig. 10)
Before moving the microscope, be sure to
remove any slide/samples. When moving the
microscope, hold the stand and base as shown
in Fig. 10 to keep it level.
Fig. 8
Fig. 9
Fig. 10

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 15
SPECIFICATIONS
System 374 6.3:1 Parallel Zoom Body
Objective
Lens
Working
Distance
(mm)
EYEPIECE
WF 10X (Ø24mm)
Total
Magnification
Visual Field
(mm)
0.5X 186 4X – 25X 60 – 9.6
1.0X
78
8X – 50X
30 – 4.8
System 374 Trinocular Optical Data
MAGNIFICATION*
Accessory
Lens
Magnification
with Zoom @ 0.8
FOV (mm) with
Zoom @ 0.8
Magnification
with Zoom @ 5
FOV (mm) with
Zoom @ 5
Working Distance
1.0X 23.1X 22.7 148.4X 3.6 78
0.5X 11.5X 45.4 74.2X 7.3 186
*1/2.8” CMOS HD camera with 22” monitor and 0.5X video adapter

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 16
TROUBLESHOOTING
Under certain conditions, performance of this unit may be adversely affected by factors other than
defects. If a problem occurs, please review the following list and take remedial action as needed. If you
cannot solve the problem after checking the entire list, please contact your local dealer for assistance.
Trouble Cause Remedy
Double images Interpupillary distance is not correct Readjust it – page 12
Diopter adjustment is not correct Readjust it – page 12
Dirt appears in the view field Dirt on the specimen Clean specimen
Dirt on the surfaces of eyepieces Clean eyepieces
Image is not clear Dirt on the surface of objectives Clear objectives
Image is not clear while focusing
change
Diopter adjustment is not correct Readjust diopter – page 12
Focusing is not correct Readjust it – page 12
The focusing knob is not smooth The focusing knob is too tight Loosen it to a suitable position
– page 13
The image is obscure because of the
head slipping down during
observation
The focusing knob is too loosen Tighten it to a suitable position
– page 13

SYSTEM 374 STEREO MICROSCOPES
UNITRON® 73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com 17
MAINTENANCE
Please remember to never leave the microscope with eyepieces removed and always protect the
microscope with the dust cover when not in use.
SERVICE
UNITRON®microscopes are precision instruments which require periodic servicing to keep them
performing properly and to compensate for normal wear. A regular schedule of preventative maintenance
by qualified service personnel is highly recommended. Your authorized UNITRON®distributor can
arrange for this service. Should unexpected problems be experienced with your instrument, proceed as
follows:
1. Contact the UNITRON®distributor from whom you purchased the microscope. Some
problems can be resolved simply over the telephone.
2. If it is determined that the microscope should be returned to your UNITRON®distributor or to
UNITRON®for warranty repair, pack the instrument in its original Styrofoam shipping carton. If you no
longer have this carton, pack the microscope in a crush-resistant carton with a minimum of three inches
of a shock absorbing material surrounding it to prevent in-transit damage. The microscope should be
wrapped in a plastic bag to prevent Styrofoam dust from damaging the microscope. Always ship the
microscope in an upright position; NEVER SHIP A MICROSCOPE ON ITS SIDE. The microscope or
component should be shipped prepaid and insured.
LIMITED MICROSCOPE WARRANTY
This microscope is warranted to be free from defects in material and workmanship for a period of five (5) years for
mechanical and optical components and one (1) year for electrical components from the date of invoice to the original
(end user) purchaser. This warranty does not cover damage caused in-transit, misuse, neglect, abuse or damage
resulting from improper servicing or modification by other then UNITRON® approved service personnel. This
warranty does not cover any routine maintenance work or any other work, which is reasonably expected to be
performed by the purchaser. Normal wear is excluded from this warranty. No responsibility is assumed for
unsatisfactory operating performance due to environmental conditions such as humidity, dust, corrosive chemicals,
deposition of oil or other foreign matter, spillage or other conditions beyond the control of Unitron Ltd. This warranty
expressly excludes any liability by Unitron Ltd. for consequential loss or damage on any grounds, such as (but not
limited to) the non-availability to the End User of the product(s) under warranty or the need to repair work processes.
Should any defect in material, workmanship or electronic component occur under this warranty contact your
UNITRON® distributor or UNITRON® at [phone]. This warranty is limited to the continental United States of
America. All items returned for warranty repair must be sent freight prepaid and insured to Unitron Ltd., 73 Mall Drive,
Commack, NY 11725 – USA. All warranty repairs will be returned freight prepaid to any destination within the
continental United States of America. For all foreign warranty repairs, return freight charges are the responsibility of
the individual/company who returned the merchandise for repair.