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the original type or a recommended direct
replacement. Preventive maintenance
of
transistors is accomplished
by
performing
the following steps:
a.
Inspect the semiconductors and sur-
rounding area
as
accumulations
of
dirt
or
dust
could
fonn
leakage
paths.
b. Examine all semiconductors for loose
connections
or
corrosion.
5.4.3.2. Capacitors
Preventive maintenance
of
capacitors is
accomplished as follows:
a.
Examine
all capacitor terminals for
loose connections
or
corrosion.
b. Ensure that component mountings are
tight.
c. Examine the body
of
each capacitor for
swelling, discoloration,
or
other evi-
dence
of
breakdown.
d. Inspect electrolytic capacitors for leak-
age signs.
e. Use standard practices to repair poor
solder connections with a low-wattage
soldering iron.
5.4.3.3.
Fixed
Resistors
Preventive maintenance
of
fixed resistors
is accomplished by the following steps:
a.
When inspecting a chassis, printed-cir-
cuit board,
or
discrete component as-
sembly, examine resistors for dirt
or
signs
of
overheating.
Discolored
,
cracked,
or
chipped components indi-
cate a possible overload.
b. When replacing a resistor ensure the
replacement value corresponds to the
component designated by the schematic
diagram.
c. Clean dirty resistors with a small brush.
5.4.3.
4.
Transformers
Preventative maintenance
of
transformers
is accomplished by performing the follow-
ing:
a.
Feel each transformer soon after power
removal for signs
of
overheating.
b. Inspect each transformer for dirt, loose
mounting brackets and rivets, loose ter-
minal connections, and insecure con-
necting lugs. Dust, dirt,
or
moisture be-
tween terminals may cause flashovers.
c. Tighten loose mounting lugs, terminals,
or
rivets.
d. Clean with a dry lint-free cloth. Use an
approved cleaning solvent
if
required.
e. Clean corroded contacts
or
connections
with crocus cloth.
f.
Replace defective transformers.
5.4.3.5.
Meters
Preventative maintenance
of
meters is ac-
complished as follows:
5-2
a.
Inspect for loose, dirty,
or
corroded
mountings and connections.
b. Examine leads for frayed insulation and
broken strands.
c. Check for cracked
or
broken plastic
cases and cover glasses.
d.
Tighten
loose
mountings
or
connec-
tions. Since meter cases are made
of
plastic, exercise care to prevent break-
age.
e. Clean m
/t
er cases and glass cover with
adrycl
9
~•
f.
Remove dirt from mountings and con-
nections with a stiff brush.
g.
Remove corrosion with crocus cloth.
5.4.3.6. Relays
Replace hermetically sealed relays
if
de-
fective.
Nonhermetically sealed relays are consid-
ered normal if:
a.
The relay is mounted securely.
b. Connecting leads are not frayed and the
insulation is not damaged.
c. Terminal
connections
are tight and
clean.
d. Moving parts travel freely.
e. Spring tension is correct.
f.
Contacts are clean, adjusted properly
and make good contact.
g. The coil shows
no
signs
of
overheating.
h. Clean any dirty
or
corroded terminal
connection or switch section with crocus
cloth.
5.4.3.7.
Switches
Preventative maintenance
of
switches is
accomplished
by
checking the following:
a.
Inspect switches for defective mechani-
cal action or looseness
of
mounting and
connections.
b. Examine cases for chips
or
cracks.
Do
not disassemble switches.
c. Inspect accessible contact switches for
dirt, corrosion, looseness
of
mountings
and connections.
d. Check contacts for pitting, corrosion, or
wear.
e. Operate the switches to determine
if
each moves freely and is positive in ac-
tion.
f.
Tighten
all
loose
connections
and
mountings.
g. Replace defective switches.
5.5.
Corrective Maintenance
Corrective maintenance
lur
the transmit-
ter is limited by the objective
of
minimum
down time, Maintainahility
,mil
r.~rP.
~rP.
considerably simplified for operation and
maintenance personnel as the transmitter is
designed and built with highly reliable and
proven elements to minimize down time.
888-2312-001
5.5.1. Troubleshooting
Most troubleshooting consists
of
visual
checks. Because
of
high voltages present in
the transmitter, it is not safe to work with
the power energized.
The meters, indicators, and fuses should
be
used
to
determine
which
stage
is
malfunctioning. The meters which indicate
transmitter operating parameters are lo-
cated across the front
of
the cabinet. All
tuning controls are adjustable
in
view
of
the
meters. Internal components
may
be ac-
cessed from both the front and rear
of
the
transmitter.
In
event
of
problems, isolate the trouble
area
tooneofthefollowing
with the meters
and indicators for each section:
a. Antenna and Feedline
b. Control Circuits
c.
Splitter (HT
lFM
only)
d. PA Section(s)
e. Exciter
When the trouble is isolated to a specific
area, refer to the theory section
of
this tech-
nical manual for circuit discussion to aid in
problem resolution.
Tables
5-1 and Table 5-2 lists some typical
trouble symptoms, probable causes, and
corrective actions pertaining to the overall
Transmitter and to the Controller. The cor-
rective action given for a trouble symptom
is not necessarily the only answer to a prob-
lem. It only tends to lead the repairman into
the area that may
be
causing the trouble.
In
event parts are required, refer to Section
VI,
Parts List.
Prior to starting a troubleshooting proce-
dure check all switches, power cord connec-
tions, connecting cables, and power fuses.
5.6.
Technical Assistance
HARRIS
Technical and Troubleshooting
assistance is available from
HARRIS
Field
Service during normal business hours
(8:00
AM to 5:00
PM
Central Time). Emergency
service is available
24 hours a day. Tele-
phone
217/222-8200 to contact the Field
Service Department or address correspon-
dence to Field Service Department,
HAR-
RIS
CORPORATION
, Broadcast Division,
P.O. Box
4290, Quincy, Illinois 62305-
4290,
USA. The HARRIS factory may also
be
contacted
through
a
FAX
facility
(217/222-7041)
or
a
TELEX
service
(247319).
5
.7
. Alignment Procedures
This section
of
the manual will cover all
procedures required to align the modules
and assemblies in the Transmitter. These
procedures will be listed for each
of
the
modules requiring alignment
or
adjust-
ment. Ad justrnents required for a frequency
WARNING:
Discorn
;,·
,t
primary power prior to servicing.
----
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