Tektronix 1L30, Instruction Manual

Page: 39 / 129

Maintenance — Type 1L30
tion or every six months if the instrument is used intermit­
tently. The calibration procedure is helpful, in isolating
major troubles in the instrument, or in locating minor
troubles which are not apparent during regular operation.
Instructions on how to conduct a performance check are
provided in Section 5, Calibration instructions ore described
in Section 6.
CORRECTIVE MAINTENANCE
Corrective maintenance consists of component replace­
ment and instrument repair. Special techniques or pro­
cedures required to replace components in this instrument
are described, in this section.
NOTE
M ain ten an ce or repair of the RF assembly, (o s ­
cillator, mixer and filte r) should only be a tte m p t­
ed if ad e q u a te facilities and q ualified personnel
are a v a ila b le . W e recommend when -possible that
the entire unit be returned to a Tektronix Repair
Center. Contact your local Field O ffice or Repre­
sentative. Replacem ent instructions for the assem­
bly, the oscillator tubes and mixer diodes are p ro­
vided in this section.
Test equipm ent and c a li­
bration fixtures required to ca lib ra te these assem­
blies are listed in the C alib ratio n section of the
m anual, plus a procedure to ca lib ra te the RF sec­
tion.
TABLE 4-1
C om ponent Num bering
Com ponent
N o . Series Circuit
D iagram
1-99
RF Section
1
100-149
Wide-Band Amplifier & Mixer
4
150-199
IF Attenuator
5
200-399 Sweeper Circuit
3
400-499
Narrow-Band Amplifier 6
500-560
Variable-Resolution Amplifier 7
600-727 Output Amplifier
8
800-890 Phase Lock Circuit
2
Resistor Color Code
The instrument contains a number o f stable metal-film
resistors identified by their gray background color and color
coding. If a resistor has three significant figures and a
multiplier, it will be EIA color coded. If it has four signifi­
cant figures and a multiplier, the value will normally be
printed on the resistor. For example, a 332 kQ resistor will
be color coded, but a 332.5 kQ resistor will have if value
printed on the resistor body. The color-coding sequence
is shown in Fig. 4-1.
Obaining Replacement Parts
Local Purchase. All electrical and mechanical parts re­
placement can be obtained through your local Tektronix
Field Office or representative. Many of the standard elec­
tronic components however, can be obtained locally in less
time than is required to order from Tektronix, Inc. Before
purchasing or ordering replacement parts, consult the Parts
List for value, tolerance and rating. The Parts section con­
tains instructions on how to order these replacement parts.
NOTE
W hen selecting the replacem ent parts, if is im ­
p ortan t to remember that the physical size and
shape of the component may affect its p erfo rm ­
ance in the circuits
Component Numbering and Ide n tificatio n
The circuit number of each electrical part is shown on
the circuit diagrams. A functional group of circuits (such
as the RF Section) is assigned a particular series of num­
bers. Table 4-1 lists the assigned component numbers for
the various circuits.
Switch wafers are identified by counting from the first
wafer located behind the detent section of the switch towards
the last wafer. For example, the designation 2R printed by a
switch section on a schematic identifies the sv/ich section
as the rear side of the second wafer when counting back
from the switch detent section.
— 1st Sig. Fig.
— 2nd Sig. Fig.
— 3rd Sig. Fig.
•— Multiplier
i— Tolerance
Color
1st
Sig.
Fig.
2nd
Sig.
Fig.
3rd
Sig.
Fig.
Multiplier
Tolerance
l ± l %
Black 0 0
0
1
—
Brown
1 1 1
10
1
Red 2
2
2
100
2
Orange
3 3
3
1,000
—
Yellow 4 4
4
10,000
—
Green
5 5
5
100,000
0.50
Blue
6 6
6
1,000,000
0.25
Violet
7 H 7
7
10,000,000
0.10
G ray
8 8
8
100,000,000
0.05
White
9 9
9.
1,000,000,000
Gold |
0.1
5
Silver |
0.01
—
N o Color 1
10
Fig. 4-1.
S t a n d a r d
EIA color-coding of metal-film
r e s is t o r s .
4 -2 ©