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Page 23
IN CASE OF DIFFICULTY
_-action of the Manual is divided into two parts. The
Dart, titled "General Troubleshooting Information,"
ibes what to do about the difficulties that may occur
t after your Clock is assembled.
.79 second part, titled "Troubleshooting Chart," is provided
to assist you in servicing the Clock if the "General
Troubleshooting Information" fails to clear up the problem,
if
difficulties occur after your Clock has been in use for
E.ome time. The "Troubleshooting Chart" lists a number of
Dossible difficulties that could arise along with several
Dossible solutions to those difficulties.
Try to analyze the symptoms of any problem you might
lave
before starting any troubleshooting procedure. This can
_sually be accomplished by trying the various functions of
.cur
Clock to determine abnormal operations. A review of
=e
"Operation" section above may help your analysis.
OTE: Refer to the "Circuit Board X-Ray Views" on Pages
28
and 29 for the physical location of parts on the circuit
uoards.
GENERAL TROUBLESHOOTING INFORMATION
Check all the wires that are connected between the
two circuit boards and between the circuit boards and
other parts. Trace each wire in colored pencil on the
Pictorial as it is checked. Make sure these wires are
connected to the proper points and are properly
soldered. Someone who is not familiar with the unit
may notice something you have consistently
overlooked.
Be sure the IC is seated properly in its socket.
About 90% of the kits that are returned for repair do
not function properly because of poor connections
and soldering. Therefore, many troubles can be
;ocated by a careful inspection of connections to make
sure they are soldered as described in the "Soldering"
section
of the "Kit Builders Guide." Reheat any
doubtful connections.
C.7.;osely examine each circuit board foil in a good light
to see that no solder bridges exist between adjacent
connections. If available, a magnifying glass would be
-,
eipful for this purpose. Remove any solder bridges by
a clean, hot soldering iron tip between the two
that are bridged until the excess solder flows
onto the tip. Compare your foil pattern against
M- 7
"X-Ray Views" on Pages 28 and 29.
5.
Be sure each transistor is in its proper location (correct
part number and/or type number). Be sure that each
transistor lead is in the right hole and has a good
solder connection to the foil.
6.
Check the integrated circuit for proper positioning.
(Be sure the dot or notched end of the IC is over the
half dot printed on the circuit board.)
7.
Check each capacitor value. Be sure that a capacitor of
correct value is installed at each capacitor location.
Check each electrolytic capacitor to be sure the lead
near the positive (+) marking is at the correct position.
8.
Check each resistor value carefully. It would be easy,
for example, to install a 2200 S2 (red-red-red) resistor
where a 22 kS2 (red-red-orange) resistor is called for. A
resistor that is discolored, or cracked, )or shows any
sign of bulging would indicate that it is damaged and
should be replaced. Since damaged resistors are often
the result of some other difficulty (such as faulty
wiring), you should try to find out what caused the
damage before you replace the part.
9.
Be sure the correct diode is ins-talled° at each diode
location, and that the banded end is positioned
correctly.
10.
Check all component leads connected to the circuit
boards. Make sure the leads do not extend through the
circuit board and come in contact with other
connections or parts.
If you still cannot locate and correct the trouble after the
above tests are completed, and if a voltmeter is available,
check your Clock's voltages against the voltages shown on
the Schematic Diagram (fold-out from Page 31) and in the
"Circuit Board Voltage Charts" (Page 30).
NOTE: In an extreme case where you are unable to resolve a
difficulty, refer to the "Customer Service" information
inside the rear cover of the Manual. Your Warranty is
located inside the front cover of the Manual.
WARNING: Hazardous voltages are exposed in the Clock
when the cabinet top is removed and the line cord is plugged
into the AC outlet. See "Chassis Photograph" on Page 27.
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