7D14
SECTION
4
MAINTENANCE
Change
information, if
any, affecting this section will be found at the rear of this manual.
Introduction
This
section
of the manual
contains maintenance infor
mation for
use
in preventive maintenance, corrective main
tenance, and troubleshooting of the 7D14.
Further
maintenance
information relating to component
color
codes and
soldering techniques can be found in the
instruction
manuals for
the 7000-series oscilloscopes.
PREVENTIVE
MAINTENANCE
General
Preventive
maintenance,
consisting of
cleaning, visual
inspection,
lubrication, etc., performed on
a regular basis,
will improve
the
reliability of this instrument. Periodic
checks on
the semiconductor devices used in the unit are
not
recommended as a
preventive maintenance measure.
See
semiconductor-checking
information given under
troubleshooting.
Lubrication
Use a
cleaning-type lubricant on
shaft bushings, inter
connecting
plug
contacts, and switch contacts. Lubricate
switch
detents with a heavier grease. A lubrication kit con
taining the
necessary lubricating
materials and instructions
is
available through
any
Tektronix Field Office. Order Tek-
tronix Part No. 003-0342-00.
Recalibration
To ensure accurate
measurements, the
7D14 should be
checked
after each 1000 hours of operation
or every six
months
if
used infrequently. A complete performance
check procedure is given in Part I
of Section 5.
The
performance check
procedure can be helpful in iso
lating
major troubles
in the unit.
Moreover, minor troubles
not apparent
during
regular
operation may
be revealed and
corrected.
TROUBLESHOOTING
Cleaning
Avoid
the use of
chemical cleaning
agents which
might
damage the plastics
in this instrument. Avoid
chemicals
containing benzene, toluene, xylene, ace
tone, or
similar solvents.
General
\
The following is
provided to
augment information con-
/tained
in other sections
of this manual for use in trouble
shooting
the
7D14. The schematic diagrams.
Circuit
Description,
and Calibration sections should be used to full
advantage.
The
Circuit Description section gives detailed
information
on circuit behavior and output requirements.
Front
Panel.
Loose
dust may be removed with a soft
cloth
or a dry brush.
Water and mild detergent may
be
used;
however, abrasive
cleaners
should
not be used.
Troubleshooting
Aids
Diagrams.
Circuit
diagrams
are given on foldout pages in
Section
7. The
circuit number and electrical value
of each
component
in this instrument are
shown
on the diagrams.
Important
voltages
are also shown.
Interior.
Cleaning
the interior of the unit should precede
calibration,
since the cleaning process could alter the set
tings
of the
calibration adjustments. Use
low-velocity com
pressed
air
to blow off the accumulated dust.
Hardened dirt
can be
removed with a soft, dry brush, cotton-tipped swab,
or
cloth
dampened with a mild detergent and water solu
tion.
Circuit Boards.
The
circuit
boards used in the 7D14 are
outlined
on
the schematic diagrams, and
a photograph
of
each
board
is
shown on the back
of the circuit diagram
foldout
pages. Each board-mounted electrical component is
identified
on
the photograph by
its circuit number.
4-1
Summary of Contents for 7D14
Page 4: ...7D14 ...
Page 11: ...Operating Instructions 7D14 Fig 2 1 7D14 front panel controls and connectors 2 2 ...
Page 33: ... 3 13 Fig 3 11 Logic diagram for Zero Cancel Logic stage Circuit Description 7D14 ...
Page 38: ...3 18 Fig 3 16 Time Base and Control circuit detailed block diagram Circuit Description 7D14 ...
Page 44: ...NOTES ...
Page 46: ...NJ Fig 4 1 Electrode configuration for semiconductors in this instrument I ...
Page 68: ...NOTES ...
Page 96: ... 7DI 4 DIGITAL COUNTER UNIT ...
Page 98: ...GRS 0371 BLOCK DIAGRAM ...
Page 99: ......
Page 103: ...0 0 I 200 mV 500 µs 0 001 200 mV 500 µs 0 001 MHz 00 mV E 00 µs 0 001 MHz ...
Page 106: ...1 ...
Page 110: ...A2 Logic Circuit Board Assembly jQ798i 798 jc743 CR744t uni R724 R742 JL744S FrR796 ...
Page 113: ......
Page 114: ...P 0 A2 LOGIC BOARD ...
Page 121: ... A B D t F H J NPR Tj ZWX V A AC M AEA HUM qAZ DEF HJ N P R S T J V V7X y ABM APAI AA 7DI4 ...
Page 129: ......
Page 130: ...4 7D14 DIGITAL COUNTER ...