Elecraft K2 Owner's Manual - Manual (Page 27)

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E
LECRAFT ®
Install another 3/16" (4.8 mm) diameter x 1/4" (6.4 mm) long
round standoff on the top of the PC board, on the left side of the large
square hole in the middle of the board. The standoff mounting hole is
below C2. Use the same hardware as indicated in Figure 5-5, including
two #4 lock washers and one chassis screw.
Install two 1/4" (6.4 mm) diameter x 1/2" (12.7 mm) long hex
standoffs on the bottom of the board (Figure 5-6). The holes for these
standoffs are indicated by large pads on the top and bottom of the
board. Use one lock washer and a chassis screw for each standoff.
Insert the lock washer between the standoff and PC board.
Bottom of
PCB
Figure 5-6
Identify the two different types of panel-mount potentiometers.
Four of them are 5-kohm linear-taper types, labeled "B5K". The fifth
is an audio-taper type, labeled "A5K". They may be physically
identical or have slightly different shafts, body colors, etc.
i
When you install the panel-mount potentiometers in the
next two steps, do not push on the shafts, which may damage the
part. Push only on the metal frame.
Install the audio-taper potentiometer, R3, in the lower left-hand
corner. (The PCB is labeled "AUDIO" at R3.) Push only on the
frame, not the shaft. Make sure that the potentiometer body is parallel
to the PC board and is pressed against the board as far as it will go
before soldering.
Install the four 5-k linear-taper potentiometers at R1, R2, R4, and
R5. (The PC board is labeled "LINEAR" at each pot.) Verify correct
positioning as you did in the previous step.
i
Before installing J1 in the following step, review Figure
3-3 (page 8) to be sure you have J1 on the correct side of the
board.
The front panel attaches to the RF board via J1, a 20-pin single-
row female connector. Install J1 on the bottom side of the board
(Figure 5-7). Solder just two pins, one at either end.
Bottom side of
PC Board
J1
Figure 5-7
Re-heat the two end pins and press the connector down until J1 is
seated flat against the board, then solder the remaining pins.