Elecraft KXB3080 - Manual (Page 13)

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Solder C1 in position, working from C1’s side of the PCB. Use minimal solder to ensure no fillet or
solder bump forms on the relay side. The relay will mount over C1’s pads and must rest directly against the
PCB. Take care not to fill the adjacent solder pads.
Strip the insulation from a 1” length of the green hook-up wire.
Use your needle-nose pliers to bend the wire at right angles about 1/16” (1.5 mm) from one end. Place
the short end in the inductor common wire solder pad (see Figure 9) and verify that the wire does not stick
out on the relay side of the PCB. If it does, trim the short end as needed.
Lay the PCB down so the circular toroid outlines are facing upward and position the short end of the
wire in the inductor common wire pad with the wire extending off the nearest edge of the board. The wire
is shown in place in the right hand photo in Figure 8.
Solder from the toroid side of the PCB just as you did for C1. Like C1, there must be no excess lead
or bump of solder on the relay side of the PCB.
i
When installing relay K1 in the following steps, be sure the relay is oriented correctly before
soldering. Otherwise your KX1 will not work.
Identify pin 1 on relay K1 (G6K-2P). There should be a dark grey bar on the relay top over the corner
above pin 1. You can confirm pin 1 by using your DMM to measure the resistance between it and pin 8 at
the same end. The resistance should be about 230 ohms.
Position K1 on the LPF1 PCB inside the rectangular outline with pin 1 next to the number 1 silk-
screened on the PCB. Be sure the relay is resting against the PCB and not against any excess solder or leads
left from installing C1 or the common inductor wire. Most relays have small raised feet on the sides that
touch the PCB when it is properly mounted, leaving a very tiny gap between the rest of the relay case and
the PCB. This is normal.
Solder only two opposite corner pins of the relay and verify that the relay is flat against the PCB. If
not, reheat the soldered pins while pressing the relay against the PCB until it is fully seated.
Solder the remaining pins and trim them flush with the PCB.
Strip the insulation from a 1” (2.5 cm) length of the green hookup wire. Save the insulation. Solder the
1” (2.5 cm) bare wire into the “+” pad on the LPF1 PCB (see Figure 8) with the wire extending out of the
pad on the relay side. Flush cut any excess wire or solder from the toroid side of the PCB (Figure 10).