Kenwood TS-670 Instruction Manual page 31

@ 4-23 INSTALLING OPTIONAL FILTERS
te tf FETITTT
e)
ae a YK-88C
O°
YK-88CN
00-048 1-8%x
a ie
YK-88A
Installing YK-88A
Installing the optional filters
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
Remove the power connector from the radio.
Using a #2 philips screwdriver, remove the top cover
(8 screws). Be careful of the speaker lead, which may
be unplugged.
Loosen the two side screws and remove the 2 screws
securing the IF unit bracket. Swing the bracket up
slightly to access and remove the two heat sink
screws. Swing the assembly down.
Remove 7 screws from the IF unit. Switch the board
forward. Protect the top of the front panel from scrat-
ching.
Using a 45 W (or less) soldering pencil, clear the 6
holes for the filter, if they are filled with solder. When
installing an AM filter, first remove R5 on the IF unit.
There is no polarity to the filter. Install the filter into its
Position on the IF unit. Solder the 2 mounting tabs, and
the 4 input and output pins to the circuit board. Solder
sparingly, and heat the connections only long enough
to insure a good solder joint. Don't overheat the filter
or circuit board.
Carefully inspect your soldering. Be certain that all pins
are actually soldered, and that you have not soldered
across any spots on the board or between any of the
pins on the filter. Clip the pins flush to the board.
Replace the IF unit in its place. Make certain no wires
will be pinched underneath the board. Replace the 7
screws for the board, plus the two heat sink screws.
Tighten the 2 side screws and replace the 2 rear
bracket screws, (See that the wire harness does not in-
terfere with the PG scan speed control).
Move the connection as illustrated when an AM filter is
installed.
(10)Reconnect the speaker lead, and reinstall the top
cover.
(11)Apply power and verify your work. Filter installation is
now complete.
29