DX Engineering DXE-AOKC-17M, Manual, Page: 2 / 16

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The DX Engineering DXE-AOKC-17M kit adds 17 meter coverage to the Hustler BTV series of
vertical antennas without giving up any existing band coverage. This kit will operate across the
entire 17 meter band, 18.068 through 18.168 MHz. The
DXE-AOKC-17M 17 Meter Add-On Kit
has a very wide SWR bandwidth, so adjustment of the tuning rods is typically not critical. The
minimum SWR will vary from as low as 1.2:1 to over 1.6:1, depending upon several variables. Even
if the minimum SWR is over 100 kHz away from the 17 meter band, the resulting SWR in the band
is typically very low. Therefore, precise adjustment isn’t necessary.
The
DXE-AOKC-17M 17 Meter Add-On Kit is rated at 1,500 watts PEP SSB, 1,000 watts CW and
is conservatively rated for RF power handling of 375 watts RTTY and Digital modes including
FT8, at antenna SWR of 2:1 and below.
Installation of the D
XE-AOKC-17M can have the effect of narrowing the SWR bandwidth of 20,
15 and 10 meters, a reasonable trade-off for adding the extra band. After the DXE-AOKC-17M is
installed and tuned, any required shift of the usable SWR frequency ranges on those bands is
accomplished by trap sleeve repositioning on the respective band trap. SWR may be optimized for
CW and digital or SSB segments by careful trap sleeve tuning adjustments.
The frequency of lowest SWR on 17 meters is affected by the presence and tuning of the
DXE-
VMN-1 Vertical Matching Network, which is required for 40 and 80 meter impedance matching.
Adjustment of tuning rods will likely be required. Optimization of the SWR only for 40 meters, with
a VMN-1 coil tap point only a couple of turns from the bottom, will typically result in a lower
minimum SWR on 17 meters. However, if both 80 and 40 meter operation is desired, then it is best
to favor 80 meters by setting resonance to an 80 meter frequency with the resonator whip length,
then adjusting the SWR to around 1.5:1 with a coil tap point above the middle turns of the DXE-
VMN-1 coil. This approach results in an elevated SWR minimum on 17 and 40 meters between
1.5:1 to 2:1 or above. Even so, the antenna is usable at full mode rated power on all bands. Keep in
mind that a 1.5:1 SWR represents only 4% reflected power and a 2:1 SWR represents only about
10% reflected power. Completely normal operations are possible at these modestly elevated SWR
levels, using a tuner when required by the transceiver or amplifier.
IMPORTANT: Running a continuous carrier power mode (FT8, AM, RTTY) on any band on
which the antenna has a trap, will create an accumulation of heat inside the trap windings,
depending upon power level and keying cycle times. When a high level of RF continues to be
applied to a trap or coil that has not sufficiently cooled, irreparable damage will occur. Aside from
conducting operations that do not interfere with others, this is a very practical reason why RF power
output must be limited to a level that accomplishes communications, when using coil loaded and
trap antennas. Typically, antenna coils and trap components cannot be operated above a 3:1 SWR.
Before operating at any power level, the antenna SWR at the operating frequency
MUST be
checked. This is especially important if high power operation is planned. This test does not include
whether or not a tuner can tune an existing high SWR. The actual
antenna SWR needs to be
double-checked. The presence of fog, rain, frost, and unknown damage or impediments, such as a
tree branch, can cause a drastic shift in the antenna system SWR curve. Simply beginning to operate
without checking the
antenna SWR , especially just starting to operate on an antenna of unknown