Maintenance—475
merit, particularly a t high frequencies. AH replace
ment parts should be direct replacements unless it is
known that a different component will not adversely
affect instrument performance.
Special Parts. In addition to the standard electronic
components, some special components are used in the 475.
These components are manufactured or selected by
Tektronix, Inc. to meet specific performance requirements,
or are manufactured for Tektronix, Inc. in accordance with
our specifications. These special components are indicated
in the Electrical Parts List by an asterisk preceding the part
number. Most of the mechanical parts used in this
instrument have been manufactured by Tektronix, Inc.
Order
all
special
parts
directly
from
your
local
T E K T R O N IX Field Office or representative.
Ordering Parts. When ordering replacement parts from
Tektronix, Inc., it is imperative that all of the following
information be included in the order to ensure receiving the
proper parts.
1.
Instrument type.
2.
Instrument serial number.
3.
A description of the part (if electrical, include the
circuit number).
4.
T E K T R O N IX Part number.
Soldering Techniques
W A R N I N G
I
Always disconnect the instrument from the power
source before attempting to solder in the instrument.
Ordinary 6 0 /4 0 solder and a 35- to 40-w att pencil-type
soldering iron can be used to accomplish the majority of
the soldering to be done in the 475. If a higher wattage
rating soldering iron is used on the etched circuit boards,
excessive heat can cause the etched circuit wiring to
separate from the board base material.
The Vertical Preamplifier Attenuator circuit boards
are made o f material easily damaged by excessive
heat. When soldering to these boards, do not use a
soldering iron with a rating o f more than approxi
mately 15 watts. Avoid prolonged applications o f
heat to circuit-board connections. Use only isopropyl
alcohol when cleaning this circuit board.
When soldering to the ceramic strips in the instrument a
slightly larger soldering iron can be used. It is recommended
that a solder containing about 3% silver be used when
soldering to these strips to avoid destroying the bond to the
ceramic material. This bond can be broken by repeated use
of ordinary tin-lead solder or by the application of too
much heat; however, occasional use of ordinary solder will
not break the bond if excessive heat is not applied.
If it becomes necessary to solder in the general area of
any of the high-frequency contacts in the instrument, clean
the contacts immediately upon completion of the soldering.
Refer to the section entitled Switch Contacts under
P R E V E N T IV E M A IN T E N A N C E for recommended cleaners
and procedures.
Component Replacement
W A R N I N G
Always disconnect the instrument from the power
source before attempting to replace components.
Circuit Board Replacement. Occasionally it may be
necessary to gain access to the reverse side of a circuit
board or to remove one circuit board to gain access to
another. The following procedures outline the necessary
steps to facilitate instrument disassembly. Most of the
connections to the circuit boards in the instrument are
made with pin connectors. However, some connections are
soldered to the board. Observe the soldering precautions
given under Soldering Techniques given in this section.
Vertical Preamp Circuit Board Removal
1.
Unplug the delay line from the Vertical Preamp
circuit board.
2.
Unplug the six coaxial cables and one wire from the
front side of the Vertical Preamp circuit board. Note wire
color codes to facilitate correct reinstallation.
3.
Unplug the two coaxial cables from the back side of
the Vertical Preamp circuit board. Note wire color codes to
facilitate correct reinstallation.
4. Unplug a 6-wire, a 7-wire, and a 10-wire ribbon cable
from the Vertical Mode Switch circuit board.
4-3
Summary of Contents for 475
Page 6: ...475 475 Oscilloscope ...
Page 20: ......
Page 46: ......
Page 151: ...A B C D E F G Fig 7 4 P 0 A4 Vertical Mode Switch circuit board ...
Page 152: ...n m m m 1 t siumm c ii im ...
Page 154: ...Diagrams 475 A B C D E F G ...
Page 155: ...GRID LOCATOR Fig 7 8 P O A3 Vertical Preamp circuit board ...
Page 157: ...Diagrams 475 ...
Page 158: ...GRID LOCATOR 2 3 4 5 6 7 8 9 1 10 11 1 12 Fig 7 10 P 0 A3 Vertical Preamp circuit board ...
Page 160: ...Diagrams 475 GRID LOCATOR Fig 7 11 A5 Vertical Output circuit board ...
Page 163: ...Diagrams 475 GRID LOCATOR Fig 7 12 P O A8 Trigger Generator And Sweep Logic circuit board ...
Page 167: ... 415 OSCILLOSCOPE B T R IG G E R G E N E R A T O R g B TR IG G E R GEN ER A TO R ...
Page 168: ...Diagrams 475 GRID LOCATOR ...
Page 172: ...SWEEP G E N ER A TO R S ...
Page 175: ...TIM IN G HORIZONTAL DISPLAY SWITCHING ...
Page 177: ...A 011 HORIZONTAL AMPLIFIER 8 l j k J Ll J Ol Z o N C O X U 1 C L O o v O o _J V v P O in r ...
Page 179: ... 476 OSCILLOSCOPE ...
Page 180: ...POWER SUPPLY ...
Page 182: ...CRT CIRCUIT ...
Page 185: ...C A L IB R A T O R A N D F A N C I R C U I T 4 C A LIB R A TO R FAN MOTOR C IR C U IT ...
Page 189: ......
Page 190: ...4 T 475 OSCILLOSCOPE FIG 1 FRO NT PANEL ...
Page 191: ...475 OSCILLOSCOPE FIG 2 MAIN FRAME ...
Page 199: ......
Page 200: ...FIG 3 RIGHT SIDE l 475 OSCILLOSCOPE ...
Page 201: ...V S X O t l B O T T OVJ 8 8 ...
Page 209: ......
Page 210: ...5 ...
Page 211: ...4 4 75 O S C ILLO S C O P E FIG 5 CAB IN ET ...
Page 215: ......
Page 237: ......
Page 241: ... 1 I R I II9A po S IT I o n f i n e I R l 130 PAGE 4 OF 5 R 1234 Ml 9 91 9 473 ...