Elecraft K1 - Manual (Page 47)

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E
LECRAFT
9. Alignment and Test, Part II
In this section you’ll align and test the transmitter stages.
Attach the side panels, then plug in the Front Panel assembly.
Make sure the Filter board is not installed.
Place the power switch, S1, in the OFF position (out).
Connect a 12 to 14-V, 1-amp power supply (or battery) to J4.
Turn on the K1. You should see E 2 7 on the LCD due to the
missing Filter board. Tap any switch to clear the message.
Place the transmitter in TUNE mode (key-down), by holding
the W P M + and W P M - switches simultaneously. The display should
show 0 . 1 watts, even though actual power output is zero.
Make the following transmit-mode DC voltage measurements.
Connect the (-) lead of the DMM to a ground jumper. Note: The
banded end of diodes is the cathode.
Test Point DC Voltage Test Point DC Voltage
J7 pin 1 5.1-6.7 D9 anode 4.3-4.6
J7 pin 4 5.9-6.1 D9 cathode 3.8-4.1
J7 pin 6 < 0.2 D10 anode < 0.2
J7 pin 8 3.8-4.1 D10 cathode 3.8-4.1
U8 pin 1 1.3-1.5 D11 anode < 0.2
U8 pin 8 5.1-5.5 D11 cathode 4.0-4.6
U9 pin 3 6.0-7.0 D13 anode 0.6-0.7
U9 pin 6 6.0-7.0 D13 cathode < 0.2
U9 pin 7 12-14
Turn off the K1. Plug in the Filter board.
Connect an antenna that is adequate for receiver testing.
Plug in a pair of stereo headphones or a speaker at J2.
Turn on the K1 and test receive performance. If receiver gain
seems to be too low, you may have an assembly error in the
transmit stages or T-R switch. Remove the Filter board and re-
check the orientation of all diodes, transistors, and ICs. Also look
for shorts on both the top and bottom of the board in the
transmitter area. (Also see Troubleshooting.)
Switch to the voltmeter display to make sure that the battery
or power supply voltage is not being pulled down when the K1 is
turned on. (Hold
D I S P L A Y once to select S-meter mode, and a
second time to select voltmeter mode.)
Preparation for Transmit Alignment
Turn the K1 off. Secure the Filter board to its three standoffs
using 3/16" (4.8 mm) pan-head screws and #4 split lock washers.
Connect a 50-ohm dummy load at the antenna jack. The
dummy load should be rated at 5 watts or higher.
Connect a key or keyer paddle.
Turn the K1 on.
Tap M E N U and locate the O U T entry (power output level).
Hold E D I T , then use W P M + and W P M - to set power to 2 . 0 watts.