Elecraft KX1 Manual - Manual (Page 36)

E
LECRAFT 35
Install electrolytic capacitor C53 (10 µF, 35 V) between diode D4
and capacitor C21 in the lower right corner of the board as follows:
_ Insert the capacitor with the longer lead through the square
pad with the + symbol printed next to it. Check to ensure the
strip and minus ( - ) sign on the capacitor is on the side
opposite the + sign on the board.
_ Solder one lead and be sure the capacitor is firmly against the
board. Measure the height above the board and confirm that it
is less than 5/16” (7.9 mm) If necessary, reheat the lead while
pressing down on the capacitor.
_ Solder the remaining lead and trim both leads.
Install the following electrolytic capacitors using the same
procedure:
_ C23 (100 µF, 10 V) about 3/4” (1.9 cm) above C53.
_ C20 (10 µF, 35 V) above C23.
_ C35 (100 µF, 10 V) next to C50 above the upper right corner
of the 3-digit display.
i
If you’re not wearing an anti-static wrist strap, be
especially careful to touch a ground frequently while installing
integrated circuits U4, U5 and U6 in the following steps.
With the board face up so that KX1 is in the upper left corner,
locate the printed outline for U4 on the right hand edge of the board
below U3. Install integrated circuit U4 (LM386) as follows:
_ Straighten the pins as necessary (see Figure 5).
_ Orient U4 so that the notch at the end is over the notch in the
printed outline on the board and pin 1 is in the round solder
pad (see Figure 11).
_ Bend the pins at opposite corners of U4 outward slightly to
hold it in place.
_ Check to be sure that U4 is resting against the shoulders of all
8 pins on the top of the board.
_ Solder and trim all 8 pins.
i
Type NE612, NE602, SA612, and SA602 integrated
circuits are all functionally identical. Any of these may be supplied
for use at U5 and U6.
Install U5 (NE/SA612 or NE/SA602) near L10 and L8 at the
lower center of the board. Use the same technique you used above.
i
In the following step, U6 must be fully seated before
soldering or it will interfere with the optional KXB30 30 m or
KXB3080 30 and 80m module. To ensure it is properly seated, a
different installation method will be used.
Install U6 (NE/SA612 or NE/SA602) near encoder Z1 at the
center of the board. Solder just one pin of U6.
Re-heat the soldered pin of U6 while pressing down on the it from
the other side. You may hear or feel it settle into a lower position on
the board. Once you’re certain that it is mounted as close to the board
as possible, solder the remaining pins.