Tektronix 503

SK
Fig. 4-4. N vviilo r »ockti d v lo ll, showing location of koy-wayt,
(lop v lo w l.
Soldering Precautions
In the production of Tektronix instruments, a special silver
bearing solder is used to establish a bond to the ceramic
terminal strips. This bond can be broken by repeated use
of ordinary tin-lead solder, or by the application of loo
much heat. However, occasional use of ordinary solder will
not break the bond if too much heat is not applied.
Soldor containing about 3% silver is generally available
commercially, or may be purchased from Tektronix in one-
pound rolls (order by Part No. 251-0514-00)
Because of the shape of the terminals on the ceramic
terminal strips, it is advisable to use a wedge-shaped tip
in the soldoring iron when removing or replacing parts from
the strips. A wedge-shaped tip allows application of heat
directly to the solder in the terminals, and reduction of the
amount of heat required. It is important to use as little heat
as possible.
TROUBLESHOOTING
Introduction
The following information is provided to facilitate trouble
shooting of the Type 503 if trouble develops. Information
contained in other sections of this manual should be used
along with the following information to aid in locating the
defective component.
Troubleshooting Aids
Diagrams. Circuit diagrams are given on foldout pages
in Section 9. The circuit number and electrical value of
each component in this instrument are shown on the dia
grams. Important voltages and waveforms are also shown
on the diagrams.
Fig. 4-S. location of n w ltlo r lo m poraturo -itoblliilng and thock-
mountlng auom bly (lo ft «ldo v lo w l.
Component Numbering. The circuit number of eoch
electrical port is shown on the circuit diagram. Each main
circuit is assigned a saries of circuit numbers. Table 4-1 lists
the main circuits in tho Type 503 and the series of circuit
numbers assigned to each. For oxample, using Table 4-1, a
resistor numbered R477 is identified as being located in the
Vertical Amplifier.
TABLE 4-1
Circuit Numbers
on Schematics
Circuit
1 99
Sweep Trigger
100-199
Sweep Generator
300-399
Horizontal Amplifier
ond Attenuator Switch
400499
Vertical Amplifier
and Attenuator Switch
600-699
Power Supply
800-899
CRT Circuit and
Calibrator
Switch W afer Identification. Switch wafers shown on
the diagrams are coded to indicate the position of the wafer
in the complete switch assembly. The numbered portion of
the code refers to the wafer number counting from the
front, or mounting end of the switch, toward the rear. The
letters F and R indicate whether the front or rear of the wafer
performs the particular switching function. For example o
wafer designated 2R indicates that the rear of the second
wafer is used for this particular switching function.
W iring Color-Code. All insulated wire used in the Type
503 is color-coded (where praticable) according to the EIA
standard color-code (as used for resistors) to facilitate circuit
© I
4-3