Tektronix TYPE Z PLIG-IN, Инструкция по эксплуатации

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O INI 4
PREVENTIVE MAINTENANCE
The Z Unit is a stable instrument, and will require com­
plete calibration very infrequently. However, to be certain
that the unit is operating properly at all times, the cali­
bration of the unit should be checked after each 500-hour
period of operation (or every six months if the unit is used
intermittently). A complete step-by-step procedure for cali­
brating the unit and checking its operation is given in the
Calibration section of this manual.
Visual Inspection
Many potential and existent troubles can be detected by
a visual inspection of the unit. For this reason, a complete
visual check should be performed every time the unit is
inoperative, needs repairs, or needs recalibration. Apparent
defects may include loose or broken connections, damaged
connectors, improperly seated tubes or transistors, scorched
or burned parts, and broken terminal strips. The remedy
for these troubles is readily apparent except in the case
of heat-damaged parts. Damage to parts due to heat is
often the result of other less apparent troubles in the unit.
It is essential that the cause of overheating be found before
replacing the damaged parts.
COMPONENT REPLACEMENT
M A I N T E N A N C E
disconnecting leads from the terminals. To remove some
switches, such as the AC-DC, Polarity, and Range, the
front overlay panel must be removed first to obtain access
to the switch mounting screws.
Single wafers on wafer-type switches are not normally
replaced. If a wafer is defective, the entire switch should
be replaced. Some switches may be ordered from the
factory either unwired or with parts wired in place, as de­
sired. Refer to the Parts List to find the wired and unwired
part numbers.
When soldering the leads to a wafer-type switch, do not
let solder flow around and beyond the rivet on the switch
terminal. Otherwise the spring tension of the switch con­
tact may be destroyed.
Turret Attenuators
To remove or to replace a component inside one of the
VOLTS/CM turret attenuators, the following instructions are
given:
1. To remove the turret, loosen the 0.050" alien set screw
(see Fig. 4-1). Grasp the knob and pull it outward far
enough to let the shaft free the turret. Do not pull the
shaft too far out or it will not hold the detent wheel in
position.
2. Remove the turret. Remove the end caps from the body
of the turret to obtain access to the components.
General
Useful information concerning the replacement of im­
portant parts in the Z Unit is given in this portion of the
manual. Because of its precision design, replacement of
close tolerance components will require calibration of the
unit to assure proper operation. Refer to the Calibration
section of this manual for a complete procedure. If the
steps in the procedure are to be performed out of sequence
to get the repaired portion of the Z Unit calibrated, refer
to the preceding portion of the procedure for more infor­
mation about control panel settings and test equipment
used.
Switches
If a switch is found to be defective and needs to be
repaired or replaced, use normal care in unsoldering and
N O TE
W hen rep lacin g an y o f the components inside the
turret, the lead lengths and parts placem ent are
critical. Duplicate the o rigin al lead lengths and
the e xa ct part placem ent. Use parts ordered from
the facto ry to assure correct ph ysical size and
to lerance accu racy. Do not use excessive heat or
let the soldering iron touch the w hite plastic part
o f the turret body. No attempt should be made
to rep lace button capacitors C 4 1 3 E , C 4 1 4 E , or
C 4 1 5 E .
These parts are sw eat-soldered in the
outer metal ring to secure a low inductance
grounding path. The ring is fitted to the body
of the turret before the inside components are
soldered into p lace . It is extrem ely u nlikely that
these capacitors w ill become defective.
H ow ­
ever, if a button cap acito r needs to be rep laced ,
order a replacem ent w ired turret body from the
facto ry.
4-1