Elecraft K1 - Manual (Page 31)

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E
LECRAFT
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Electrolytic capacitors are mounted vertically, so their PC
board outlines are circular. The (+) lead must be installed in the hole
marked with a "+" symbol. The (+) lead is usually longer than the (–)
lead, and the (–) lead is identified by a black stripe (Figure 6-6).
+
-
Figure 6-6
Install the electrolytic capacitors listed below. They must be
seated as close to the PC board as possible to avoid interfering with
option modules that you may install later. Note: The 10-µF capacitors
are of the low-profile type, so they may be smaller than the 2.2-µF
capacitors.
__ C33, __ C59, and __ C35, 10 µF (see note above)
__ C54, __ C31, and __ C67, 2.2 µF
__ C9, __ C10, and __ C53, 220 µF
8-volt regulator U5 (LM2930T-8) is a TO-220 package device
with 3 leads (see photo in parts list). Mount U5 vertically at the back
edge of the PC board (Figure 6-7). Only the wide part of the leads
should be above the board. The hole in the tab of U5 will not be used
for mounting, so positioning is not critical.
Figure 6-7
Locate the component outline for RFC8, on the bottom of the RF
board in the transmitter area. Install a short wire jumper at RFC8,
formed from a component lead or solid hookup wire.
Note: an RF choke may be supplied with the 80-meter band kit (2-
band Filter board only) for use at RFC8. This RF choke can be
installed at any time, and will have no effect on K1 alignment or
testing on any band. Its function is to improve stability on 80 meters
when the K1 is used with poorly-matched loads or an ATU.
DC Voltage Checks
Set power switch S1 to its OFF position, with the plunger out
(extended toward the back).
Connect a 12 to 14-V DC power supply or battery to J4. If your
power source does not already have a plug that mates with J4, use the
supplied mating plug and prepare a suitable power cable. The center
lead of the plug is positive (+).
Turn on S1. If you see or smell smoke, or a component feels
hot to the touch, disconnect the power source immediately. Locate
the source of trouble before proceeding.
Using your DMM's DC voltage setting, make the DC voltage
checks listed below. The (-) lead of your DMM should be connected to
one of the ground jumpers.
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Be careful not to short adjacent pins of ICs with the DMM
probe (use only a fine-point probe).
Test Point (+) DC Voltage
P1 pin 15 5.8-6.2
P1 pin 16 (supply - 0.3 V)
U3 pin 5 3.8-4.2
U3 pin 6 7.6-8.7