(c) 2020 DX Commander Limited - Page 1
10m Expedition Kit User Guide Version 1.3 May 2020
Congratulations on the purchase of your DX Commander Expedition Antenna KIT
SAFETY NOTE
DX Commander antenna components are designed for hobby radio amateurs by Callum McCormick,
M0MCX. Radio Amateurs pass exams where health and safety is included in the syllabus. Please be
careful in your handling, erection and general usage of any DX Commander parts so that yourself,
property or a third party in the vicinity of your antenna experiments remain safe. Note also that
engineered parts can have some sharp edges so be careful before handling roughly with bare hands.
Overview: The antenna runs up to 4 elements, delivering (mostly) quarter-waves with a single feedpoint and
is a similar concept to a fan-dipole, but turning the
“fan” 90 degrees on it’s X-axis and placing one side of the
fan vertically. There is a spare element slot up one side for a 10m (or 11m / CB) element too.
100m of DX10 antenna wire is also supplied. This is an arctic grade PVC wire, tested to 1,600W key down
for 65 seconds. Since there are no metal components in this antenna, I would be comfortable rating this for
double that for SSB.
With just 4 elements therefore, a user can dial in 40m (& 15m), 20m, 17m and 10m. Like the Classic, 40m
will give you 15m band as a pseudo 5/8
th
antenna. Removing the 17m band, you can turn this into a
contest/field-day antenna running 4 elements; 80m (inverted L), 40m (which also delivers 15m), 20m and
10m.
Many permutations possible. It is my opinion that for SOTA and general /P use, the favourite method will be
to run 3-elements for 40m (and 15m), 20m, 17m, depending on the sunspot cycle. Even without the 10m
element, your ATU will deliver that band. For QRO folks, a dedicated 10m element will be necessary.
You can either be very fussy and carefully tune each element for a "No ATU" system or get it "near enough"
and use your inbuilt tuner on the radio. This antenna is designed NOT to use an ATU though. In testing and
during my experiments (and during the IOTA contest - which I won!), most users (including me) achieve
better than 1.5:1 SWR across all the used bands.
Of interest, this antenna should give you a perfect tune on the 6m band. You may need to make the 40m
ever-so-slightly longer for perfection. This now becomes a 1.75 wavelength antenna which does achieve
remarkable low-angle gain, as good as a quarter wave for low to horizon DX.
Parts list
1. DX Commander Expedition 10m Pole
2. Ground Plate 3mm aluminium
3. Radiating Plate 3mm aluminium
4. Guy Plate
– UHMWPE
5. Mid Spreader UHMWPE (New for 2020)
6. Upper Spreader Plate - UHMWPE
7. SO239 Assembly with flying lead
8. Appropriate number stainless bolts
9. Appropriate number stainless wing Nuts
10. Plenty of Fork Connectors (ground)
11. Plenty of Fork Connectors (elements)
12. Stainless Hose clamps
13. Some clear tubing
14. 4mm
“marine” elastic shock cord
15. Paracord for guys
16. 16 Plastic Carabiners that snap together
17. Plenty of glue lined shrink-wrap
18. 100m DX10 arctic grade Mil-Spec wire
Please make yourself familiar with all the parts and satisfy yourself that all is present and correct. I take great
care when I pack these boxes so if something is missing, it's my fault. I do make mistakes!
In Detail
I have a user guide for the pole(s) themselves and you can find the user guide on the website under User
Guides. The pole extends to around 9.5m and is substantial enough for this use. Be careful if a storm is
forecast.
