Microprocessor Backup Lithium Battery Replacement; Fuse Replacement; Ordering Spare Parts; Adjustmentg - Kenwood TM-221A Instruction Manual

5-5. MICROPROCESSOR BACKUP
LITHIUM BATTERY REPLACEMENT
Lithium battery replacement should be performed by
an authorized KENWOOD service facility; either your
KENWOOD dealer, or the factory, since this unit con-
tains CMOS type circuitry.
Notes:
1. When the lithium battery is replaced, the
microprocessor must be reset, using the pro-
cedure in Section 4-4-2.
2. When the lithium battery fails, the radio's
microcoded functions are not affected. Only in-
formation stored in memory will be cleared.
5-6. FUSE REPLACEMENT
If the fuse blows;
DISCONNECT the AC Power Cable and replace
with the specified fuse only after determining the
cause, or contact either your KENWOOD dealer,
or the factory to repair the cause.
Warning:
1, Never connect the AC cable to the AC outlet un-
til fuse replacement has been made.
2. Never use a large amperage fuse. Replace with a
new fuse of the same rating.
This transceiver is equipped with the fuse(s) listed
below. If the fuse blows, determine the cause before
replacing the defective fuse. (Replacement fuses are
available from your authorized KENWOOD dealer.)
Part Number Q'ty
FO5-1031-05 (10 A)
for TM-221/421 series only
Fuse Location
*13.8 VDC Power
F05-8021-05 (8 A) 1 ea.
topo Cable for TM-321A and TM-521
series only
DC Power Cable | FO5-2036-05 (20 A) 2 ea.
Transceiver
Rear Panel)
*
Red 20A
Black — { So ne
20A DC Power Cable Power Input Connector
® is]
Battery
5-7. ORDERING SPARE PARTS
When ordering replacement or spare 'parts for your
equipment, be sure to specify the following:
Model and serial number of your transceiver.
Schematic number of the part.
Printed circuit board number on which the part is
located.
Part number and name, if known, and quantity
desired.
Part numbers for most replacement parts is contain-
ed in the service manual (available as an option from
your dealer).
5-8. ADJUSTMENTS
5-8-1. Cover Removal
Caution:
1. Before removing the top cover, turn the power
supply and radio POWER switches off, and
disconnect the Power Cable.
2. Do not pinch wiring when closing the cover.
Loosen the four screws on both the right and left
sides.
2. Remove the four screws attaching the top cover.
Remove the top cover and set aside.
3. Reverse steps 1 and 2 to reassemble the radio.
5-8-2. Low Power Output
Adjust VR7 on PC board to adjust the output of the
transceiver in the low power position. The adjust-
ment range is 1 to 30 watts on the TM-221 series, 1
to 20 watts on the TM-321A and TM-421 series,
and 0.5 to 5 watts on the TM-521 series.
5-8-3. Microphone Gain
Adjust VR3 on PC board to the desired level.
Caution:
Too much microphone gain can cause reports of
audio distortion.