Tektronix 475 User manual

TM 11-6625-2735-14-1
TECHNICAL MANUAL
OPERATOR’S, ORGANIZATIONAL,
DIRECT SUPPORT AND GENERAL
SUPPORT MAINTENANCE MANUAL
FOR
OSCILLOSCOPE OS-261B(V)1/U
(NSN 6625-01-101-1318)
(TEKTRONIX MODEL 475 WITH OPTION 04)
This copy is a reprint which includes
pages from Change 1. current
H E A D Q U A R T E R S, D E P A R T M E N T O F T H E A R M Y
JUNE 1982

CHANGE
No. 1
TM 11-6625-2735-14-1
C 1
HEADQUARTERS
DEPARTMENT OF THE ARMY
Washington, DC, 10 September 1984
OPERATOR’S, ORGANIZATIONAL, DIRECT SUPPORT, AND
GENERAL SUPPORT MAINTENANCE MANUAL
OSCILLOSCOPE OS-261B(V)1/U
(TEKTRONIX MODEL 475 WITH OPTION 04)
(NSN 6625-01-101-1318)
AND
OSCILLOSCOPE OS-261C(V)1/U
(TEKTRONIX MODEL 475 WITH OPTION 04
AND OPTION 07)
(NSN 6625-01-119-7314)
TM 11-6625-2735-14-1, 17 June 1982, is changed as follows:
1. Title of manual is changed as shown above.
2. New or changed material is indicated by a vertical bar in the margin of the page. Added or revised illustrations are
indicated by a vertical bar in front of the figure caption.
3. Remove old pages and insert new pages as indicated below:
Remove pages
i through iv
1-0
0-1
1-9 and 1-10
1-13/(1-14 blank)
2-1 and 2-2
6-1 and 6-2
None
7-3 and 7-4
7-15, 7-16 and 7-17/(7-18 blank)
A-1/(A-2 blank)
B-1 through B-5
D-1 through D-6
4. File this change sheet in the front of the publication.
Insert pages
C, D and E/F blank)
i through iv
0-0
0-1
1-9 and 1-10
1-13/(1-14 blank)
2-1 and 2-2
6-1 and 6-2
6-2.1 through 6-2.8
7-3 and 7-4
7-15, 7-16 and 7-17/(7-18 blank)
A-1/(A-2 blank)
B-1 through B-6
D-1 through D-6

By Order of the Secretary of the Army:
Official:
JOHN A. WICKHAM JR.
General, United States Army
Chief of Staff
ROBERT M. JOYCE
Major General, United States Army
The Adjutant General
To be distributed in accordance with DA Form 12-36B requirements for 0S-261.

TM 11-6625-2735-14-1
SAFETY SUMMARY
WARNING
WARNING
WARNING
This manual contains safety information which the user must follow to ensure safe operation of this
instrument. WARNING information is intended to protect the operator; CAUTION information is
intended to protect the instrument. The following general safety precautions must be observed during all
phases of operation, service, and repair of this instrument. Failure to comply with these precautions or
with specific warnings elsewhere in this manual violates safety standards of design, manufacture, and
intended use of the instrument.
Warning statements precede potentially dangerous procedures throughout this manual. The instruc-
tions contained in the warnings must be followed. The following warning statements are found in this
manual:
Use a proper power source. This instrument is intended to be operated from a single-phase power
source. A suitable power source is one where both current-carrying conductors are ungrounded, since
over-current protection (fuse) is provided in both conductors. Operation from a grounded power source
is not recommended. If the fuse in the grounded conductor opens, the power-source voltage appears on
the internal primary wiring causing a possible shock hazard during troubleshooting.
Ground the instrument. This instrument has a three-wire power cord with a three-terminal polarized
plug for connection to the power source and safety-earth. The safety-earth terminal of the plug is directly
connected to the instrument frame. For electric-shock protection, insert this plug only in a mating outlet
with a safety-earth contact or otherwise connect the frame to a safety-earth system. Failure to complete
the ground system may allow the chassis of this instrument to be elevated above ground potential and
pose a shock hazard.
WARNING
Avoid live circuits. Dangerous voltages exist at several points throughout this instrument. When the
instrument is operated with the covers removed, do not touch exposed connections or components.
Some transistors have voltages present on their cases. Disconnect power before cleaning the instrument
or replacing parts.
Avoid contact with chemicals. Handle silicone grease with care. Avoid getting silicone grease in eyes.
Wash hands thoroughly after use.
WARNING
Use care when handling the crt. Protective clothing and safety glasses should be worn when handling
a crt. Avoid striking it on any object which might cause it to crack or implode. When storing a crt, place it
in a protective carton or set it facedown in a protected location on a smooth surface with a soft mat under
the faceplate to protect it from scratches.
a

TM 11-6625-2735-14-1
SAFETY SUMMARY (CONT.)
WARNING
Adequate ventilation should be provided while using TRICHLOROTRIFLUOROETHANE. Prolonged
breathing of vapor should be avoided. The solvent should not be used near heat or open flames; the
products of decomposition are toxic and irritating. Since TRICHLOROTRIFLUOROETHANE dissolves
natural oils, prolongted contact with skin should be avoided. When necessary, use gloves which the
solvent cannot penetrate. If the solvent is taken internally, consult a physician immediately.
WARNING
Compressed air shall not be used for cleaing purposes except where reduced to less than 29
pounds per square inch (psi) and then only with effective chip guarding and personnel protective
equipment. Do not use compressed air to dry parts when TRICHLOROTRIFLUOROETHANE has
been used. Compressed air is dangerous and can cause serious bodily harm if protective means
or methods are not observed to prevent chip or particle (of whatever size) from being blown into
the eyes or unbroken skin of the operator or other personnel.
CAUTION
Avoid crl phosphor damage. Crt phosphor damage can occur under adverse conditions. Avoid any
condition where an extremely bright, sharply focused spot exists on the crt.

TM 11-6625-2735-14-1
SAFETY STEPS TO FOLLOW IF SOMEONE IS THE VICTIM OF
ELECTRICAL SHOCK
DO NOT TRY TO PULL OR GRAB THE INDIVIDUAL
IF POSSIBLE, TURN OFF THE ELECTRICAL
IF YOU CANNOT TURN OFF THE ELECTRICAL POWER, PULL,
PUSH, OR LIFT THE PERSON TO SAFETY USING A WOODEN POLE
OR A ROPE OR SOME OTHER INSULATING MATERIAL
SEND FOR HELP AS SOON AS POSSIBLE
AFTER THE INJURED PERSON IS FREE OF CONTACT WITH THE
SOURCE OF ELECTRICAL SHOCK, MOVE THE PERSONA SHORT
DISTANCE AWAY AND IMMEDIATELY START ARTIFICIAL
RESUSCITATION
Change 1 C

TM 11-6625-2735-14-1
WARNING
HIGH VOLTAGE
is used in the operation of this equipment
DEATH ON CONTACT
may result if personnel fail to observe safety precautions
Never work on electronic equipment unless there is another person nearby who is familiar with the
operation and hazards of the equipment and who is competent in administering first aid. When the
technician is aided by operators. They must be warned about dangerous areas.
Be careful not to contact high-voltage connections or 115 volt ac input connections when
installing or operating this equipment.
Whenever the nature of the operation permits, keep one hand away from the equipment to reduce
the hazard of current flowing through the body.
WARNING Do not be misled by the term “low voltage”. Potentials as low as
50 volts may cause death under adverse conditions.
For Artificial Respiration, refer to FM 21-11.
D Change 1

TM 11-6625-2735-14-1
SAFETY PRECAUTION
A periodic review of safety precautions in TB 385-4, Safety Precautions for Maintenance of
Electrical/Electronic Equipment, is recommended. When the equipment is operated with covers
removed, DO NOT TOUCH exposed connections or components. MAKE CERTAIN you are not
grounded when making connections or adjusting components inside the test instrument.
Change 1 E/(F blank)