160 meter alignment – Elecraft K160RX User Manual
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160 Meter Alignment
Select 160 meters (1.8-2.0 MHz) using
B A N D +
or
B A N D -
.
i
The following step is only necessary if your K2 firmware is older than revision 2.00. With
revision 2.00 and up, C AL P L L is done only once (on 40 m), so there's no need to do it on 160 m.
Set the VFO for 1800.10 kHz. Connect the K2's internal frequency counter to TP1 (VFO test point).
Use the menu to select C AL P L L , then hold
E D I T
a second time to initiate 160-meter VFO linearization.
This takes about 2 minutes, after which you should see E N D on the display. Note: If you see I N F O 2 3 1
on the display, you have probably connected the counter to the wrong test point. If you see I N F O 2 3 5 ,
then the PLL reference oscillator range may be inadequate for 160-meter coverage.
i
The 80 and 160 meter bands share the same basic band-pass filter components, with two additional
capacitors switched in on 160 meters (see RF board schematic, sheet 3). If you have a signal generator and
sensitive RF voltmeter or oscilloscope, you can optimize the settings of L3 and L4 in receive mode for
minimum loss on both bands. However, the transmit-based approach described below is also satisfactory.
Set the power level for about 2 watts using the POWER control. Set the VFO to 1840 kHz.
Connect a 50-ohm, 10-W (minimum) dummy load to the main antenna jack (J4). Use a wattmeter with
an analog meter movement if one is available, as this makes alignment a bit easier. Otherwise, you can use
the K2's internal wattmeter. Note: If you have an ATU installed (KAT2 or KAT100), connect the dummy
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160-m band-pass filter alignment.
Locate the 80/160 m band-pass filter inductors, L3 and L4, which are near the back-left corner of the
RF board. Hold
T U N E
to key the transmitter, then peak both L3 and L4 alternately for the highest power
output reading. Use only the tuning tool supplied with the K2. Note: The transmitter may already put out 2
watts even before you have adjusted L3 and L4, but you should still peak the output, which may go well
above 2 watts. The next time you hold
T U N E
, the K2's ALC will set the power to about 2 watts.
Repeat the previous step if necessary to be sure that L3 and L4 are peaked.
Set the POWER control for 10 watts, and make sure that the transmitter can attain this level at both
1800 and 2000 kHz using
T U N E
. Next, switch to 80 meters and again check for full power output at both
3500 and 4000 kHz. If you cannot reach full power at the high end of either or both bands, set the VFO to
1850 or 1900 kHz and re-peak L3 and L4 at 2 watts, then re-test.
Move the frequency counter cable to back to TP2 (BFO).
Turn off the K2. Re-connect the speaker, battery, etc., and install the top cover.