Elecraft XV Assembly Manual for XV432 MHz - Manual (Page 27)

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Secure the L brackets loosely to the front panel PCB using two 4-
40 x 3/16" (4.8 mm) screws (black). It is not necessary to use lock
washers at this time.
Adjust the L bracket positions so the front panel PCB is aligned with
the RF PCB. If the gap between the front panel PCB and the RF PCB is
wider at one end than the other, you probably have one of the brackets
installed backward. Be certain the shorter legs are attached to the RF
PCB.
P1
Top of RF board
J1
Figure 14. Installing J1 and P1.
Tighten all four L bracket screws.
Solder all pins of J1 and P1.
Remove the two screws holding the front panel PCB to the brackets.
Unplug the front panel PCB and set it aside in a safe place.
Remove the brackets and screws from the RF PCB and set them
aside.
Sort the fixed resistors by wattage and value as follows:
Divide the resistors by wattage: 3-watt (physically largest), 2-
watt, 1-watt and 1/4 watt (smallest).
Among the 1/4 watt resistors, separate the four 1% tolerance
resistors. These resistors have five color bands: four color bands
show the value plus a brown color band at one end that is wider
than the others. The wide band indicates that it is a 1% tolerance
resistor.
Sort the remaining 1/4 watt resistors by value. If the color bands
are difficult to read, use a DMM (digital multimeter) to verify
their values. Tape them to a piece of paper with the values
labeled.
Place the circuit PCB with the silk-screened side up and the
cutout to your left as shown in Figure 13. The lettering ELECRAFT
XV432 TRANSVERTER RF BOARD in lower right quadrant will read
right side up. All of the remaining parts will be installed on the top,
silk-screened side of the PCB.
i
Save the longer clipped leads from the following resistors.
You will use several of them to make jumpers and test points later.
Install the 1-watt resistors listed below. Space each resistor about
1/16” (1.5 mm) above the PCB by placing the long end of one of the
right-angle brackets between the resistor and the PCB until the resistor
is soldered in place (See Figure 15). The objective is to leave space for
air to flow around the resistor. The resistors that should be spaced
above the PCB are shown by a double silk screen outline.
R16, 120 ohm (brn-red-brn) near U1 in the upper left
quadrant of the PCB.
R12, 180 ohm (brn-gry-brn) or (181J)
R21, 820 ohms (821), next to R16.
R19, 180 ohm (brn-gry-brn) or (181J), next to U5 at the
center of the PCB.
R8, 180 ohm (brn-gry-brn) or (181J) in the lower right
quadrant.
PLACE RIGHT-ANGLE BRACKET
UNDER EACH RESISTOR UNTIL
IT IS SOLDERED IN PLACE
SOLDER & TRIM LEADS
Figure 15. Spacing the 1-watt and 3-watt Resistors above the PCB.