Tektronix 221, Инструкция по эксплуатации

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Troubleshooting Aids—221 Service
Resistor and Capacitor Color Code
Ceramic
Capacitors:
Dipped Tantalum
Electroiytics:
Color
Figures
Multiplier
Tolerance
Voltage
Rating**
Resistors
Capacitors Resistors
Capacitors
Silver _______
i a 3
___
±10%
Gold — 10”1
— ±5% — —
Black 0
1 1
—
±20% or
2 pF*
4 VDC
Brown
1 10 10 ±1%
± 1% or
0.1 p F *
6 VDC
Red 2 102
10" ±2% ±2% 10 VDC
Orange 3 103
103 ±3% ±3% 15 VDC
Yellow 4 104
104 ±4%
+ 100%
-9 %
20 VDC
Green 5
10s 105 ±0.5%
±5% or
0.5 pF*
25 VDC
Blue
6 10‘ 106
— —
35 VDC
Violet 7 —
— — — 50 VDC
Gray 8 —
10”2 —
+80%
-2 0 %
or 0.25 pF* —
White 9 — 10”'
—
±10% or
1 pF*
3 VDC
(none)
— —
—
±20%
± 10% or
1 pF*
—
•For capacitance of 10 pF or less.
•For dipped tantalum capacitors only.
N O T E :
(7)
a n d /o r @ c o lo r co d e f o r c a p a c ito rs d epends u p o n
m a n u fa c tu re r a nd c a p a c ito r ty p e . M a y n o t be p re sen t in som e cases.
^ 1) ^ 2) a n d —1 st, 2 n d , a nd 3 rd s ig n ific a n t fig u re s:
® —m u ltip lie r ; ( j f ) —to le ra n c e :
^ —te m p e ra tu re c o e ffic ie n t:
( ? ) —p o la r ity a nd vo lta g e ra tin g .
Fig. 6-2. Color code for resistors, ceramic capacitors, and dip tantalum electrolytic capacitors.
Component Color Coding
The resistors used in the 221 are either composition
resistors or precision resistors. The resistance values are
color-coded on the components w ith El A color-code (some
precision resistors may have the value printed on the body).
The color-code is read starting w ith the stripe nearest the
end of the resistor. Composition resistors have four stripes
that consist of tw o significant figures, a m ultiplier, and a
tolerance value (see Fig. 6-2). Precision resistors have five
stripes consisting of three significant figures, a m ultiplier,
and a tolerance value.
The capacitance value o f common disc capacitors and
small tubular electroiytics is marked in microfarads on the
side of the component body. The molded electrolytic
capacitors are color-coded in picofarads (see Fig. 6-2)
The cathode end of each glass-encased diode is indicated
by a stripe, a series o f stripes, or a dot.
Isolating Trouble To A Circuit
To isolate the trouble to a particular circuit, note the
trouble symptom. The symptom often identifies the circuit
in which the trouble is located. For example, no intensity
indicates that the crt circuit is probably at fault. When
trouble symptoms appear check the circuit by taking
voltage and waveform measurments. Typical voltages and
waveforms are shown on the schematics in the diagram
section o f this manual Figure 6-3 provides a guide for
locating a defective circuit.
Start from the top o f the chart and perform the given
checks on the left side o f the page. When a check is
performed that does not produce the indicated results,
further checks and/or circuits in which the trouble is
probably located are listed to the right of this step. A fter
the defective circuit has been located, proceed to locate the
defective component(s).
6-2