Tektronix 323, Инструкция по эксплуатации

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Maintenance— Type 3 2 3
Remove one screw from each end of the side control
panel, and remove the nut which is located near the inside-
center of the panel.
Remove the five screws which hold the board to the chas­
sis.
Lift the board and side panel away from the chassis,
hinging it on the cable harness at the front of the board.
Position Bracket
Remove both POSITION knobs. Remove one securing nut
and lock washer from each end of the POSITION bracket.
Move the rear of the bracket away from the chassis, as far as
the cables will allow. Then move the bracket back and out,
hinging it on the cables at the rear of the bracket.
TRIGGER Control Assembly
Remove the TRIGGER knob; then remove the nut and flat
washer from the exposed bushing. Lift the rear of the assem­
bly away from the chassis and pull it back until the shaft
clears the front panel. Note that the internal lock washer is
in place between the TRIGGER assembly and the front panel
during re-installation.
INPUT and Trig/H oriz Coupling Switches
These can be removed after two nuts have been removed
from the back, and the pressure-fit knob has been pulled from
the lever arm. To avoid damage to switch contacts, un­
solder the coupling capacitor (C20) before removing the
INPUT Coupling switch.
POWER Switch
The face plate must be removed from the Oscilloscope to
expose the two machine screws holding this switch in
place. The black-and-green plastic indicator plate should
be removed and set aside until re-assembly.
Power Regulator Enclosure
Access to the enclosure can be had by removing two nuts
and bolts from the front and one machine screw from the rear
of the cover.
WARNING
More than 2000 V is present in the enclosure when
the Oscilloscope is energized.
Fuse. The fuse (operating power) is located at the rear
of the compartment on the component side of the Power
Regulator board. It can be replaced without removing the
board. The cause of a blown fuse should be investigated
before replacing it. Only 1A- 250 V fast blow fuses should
be used as replacements. A spare fuse is provided with
the Oscilloscope and is contained in the spare-fuse holder
located near the Attenuator circuit board.
Power Regulator Circuit Board.
Access to the compon­
ent side of this board and to the other circuitry in the com­
partment can be had by removing the three screws from the
upper surface, and then lifting the board up and out, pivot­
ing it on the wiring harness at the side of the board.
Power Supply Circuit Board.
For access to the bottom of
this board, perform the following:
Remove the Power Regulator circuit board. Then unscrew
the three nylon mounting posts. Turn the Oscilloscope up­
side-down to permit two lock washers to fall free, and set
them aside until re-assembly. During re-assembly, replace the
two lock washers on the innermost machine screws.
Do not
put a washer on the outer screw.
Using the flat side of the tip of a screwdriver, push the
three plastic collets (which encircles the cables) out of their
mounting holes and up the cables. Apply moderate pressure
to alternate points on the collets until they are worked out
of the holes.
Raise up on the board, keeping it parallel to the chassis
until it is clear of the mounting screws. Then raise up its
outer edge to expose the under-side of the board.
Transformer and Toroids.
Leads should be tagged, or
a written record should be made of the connections whenever
these components are removed. The windings can be recog­
nized by the point at which they leave the assembly; the
ends can be distinguished either by lead length or by color
code. Do not untwist any of the paired leads.
VO LTS/D IV, T IM E /D IV , FOCUS and
INTENSITY Control Assemblies
The front casting must be loosened and swung down and
forward in order to remove these controls. Proceed as fol­
lows:
Remove the CRT and shield, following the previously-
given directions. Using a inch alien wrench, loosen two
set screws in the VOLTS/DIV knob and two in the TIME/DIV
knob. Loosen one set screw in each of the variable knobs
and in the POSITION knobs and the TRIGGER knob. Pull
all of the knobs (except for the POWER switch) off their
shafts.
Remove the four machine screws which fasten to the chassis
frame posts.
Remove the screw which holds the frame post and Power
Pack toggle clamp to the chassis, and remove the frame
post.
Open the Power Regulator Enclosure and remove the Power
Regulator circuit board. Remove the machine screw from
the frame post, moving the foil shield as necessary. Remove
the frame post from the assembly.
The front casting can now be swung down and forward
sufficiently to permit access to, or removal of, the controls
under consideration.
LOW BATT Indicator
The indicator lamp is soldered to the base cap which is
snapped in place over the indicator holder. To remove it,
force the cap off the holder.
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