so today ladies and gentlemen i'm going to show you how to build the no atu multiband
dx commander classic but sometimes i'll refer maybe to the expedition kit or the rapide
all are fundamentally the same just different dimensions and uses really so if you're an antenna
builder this will be interesting to you but you might like just to watch for the fun of it too
okay firstly let's just briefly cover what this is so the dx commander concept has a number
of quarter wave elements made out of wire that rise vertically from a radiating plate
and simply put the resonant frequency is automatically selected by the very nature of
the laws of physics there's no switches or control lines each element works completely independently
as a fan dipole mode now this style of vertical relies on some ground to be able to offer it
operate efficiently which is why we supply some extra wire for the radials that go out
on the ground radials don't need to be long my holiday setup has 30 radials
and that's 10 feet long about 3 meters and i can work down to 80 meters quite happily
and for permanent installations yes of course you can add more radials and increase your your
efficiency quarter wave radiators have a pattern that is superb for low angle takeoff low angle
you know great for dx so the 40 meter element also works perfectly on the 15 meter band 21 megahertz
it's a harmonic of 40 meters and that gives you about an extra 3 db of gain down low when used
with a moderate ground and the user guide is found here it's in pdf format i'll be referring to that
a couple of times in this video so what's in the box well loki wraps us um corrugated cardboard
in the poll he slides it inside a heavy box along with a wire then we also get the pre-drilled
tapped aluminium plates the tab is already bent up to accept the so239 that's supplied as well
you get the ultra high molecular weight polyethylene uhm wpe plastic their plates
and they're the guides for the elements they also the elements connect to them and we also use them
for dying as well so wendy pax has nuts bolts and washers that gives you everything you need
to complete the project apart from some guying stakes and you get a few spares of odds and
ends as well so you should have plenty in the kit to make it the dx10 wire now depending on
the kit it comes with either a single run of dx10 that's 100 meters 300 something feet sometimes two
reels sometimes some of the kits have four reels and the ultimate kit's got six reels
so the first thing we need to do is refer to the element cut chart in the instructions in
the user guide and cut your elements now in this video when i built the rapid you can watch me as
i reel off these elements i measure them out fit the fork connectors and also the loops at
the end of each element i haven't refilmed that because it's just me reeling wire off
and putting loops and full connectors on i happen to have labeled these for a bit of fun
too with some cube markers found on ebay on this build i used some coloured tape so now i've made
the elements the cut chart and i cut and made the radials as well let's go out the field and get
this amazing antenna working now i normally use garden chairs or cheap diy saw horses to support
my telescopic pole to erect the pole by twisting each section pulling it very firmly indeed and by
the way a quick note when you take it down nest it in the right order because if one of the smaller
top sections should drop down before the others you could end up shredding one of the sections
as you attempt to ram it all back together again so just be careful about that the ground plate is
held in place by the screw cap at the base of the telescopic pole and the driven plate plate
is held in place with a supplied hose clamp and some tubing the plastic plates can only go on the
pole one way all right the largest diameter plate goes at the you know further down the bottom and
the smallest diameter holes go near the top you'll find there's only one place these plates can go
just slide them on until they stop at the time of making this video we supply a stay up kit with
eight hose clamps and some tubing however very soon we will instead be supplying some 3m tape
together with some special cable ties this build incorporates this future style additionally for
serious permanent use i recommend adding some self amalgamating tape which seals each join
from the elements i'm going to go over this self amalgamating tape with this 3m 10 flex tape in
the future this will be supplied with the kit as well and once you're happy with the tape joins i
cable tie each join to stop the tape collapsing and the pole can't go anywhere and you basically
work your way to the end i didn't cable tie the last two sections and i did this a few weeks ago
it's still up there as i said i color coded my elements with the color of the rainbow red orange
yellow green blue and that sort of thing and let's just talk about the base if you're building this
with six elements you will have a spare stud opposite the so239 this is because i've built
the whole pattern for either three four or six equidistance elements the spare stud would only
be used in the four element layout regardless it's good practice to make sure all your plates
are exactly the same plane as the spare stud and i'm just showing you that here keen observers will
also notice i'm using some prototype aluminium ground plates these were made for me as a test
with a push fit threaded insert however you'll use the six mil quarter inch nuts
bolts that we supply i'm just testing these out for a potential upgrade in the future
anyway you thread the bolts in gently tighten as a permanent fixture without stripping the threads
just tighten no more is fine i'm showing you this on the rapid build basically it's a smaller
version of the classic how you fit the stainless washers the wing nuts over the top i mentioned the
hose clamps so we'll still supply this hose clamp look at the base certainly whilst we
continue making this style of plate set initially you just undo the clamp slip slip over uh some
tubing tighten it back up again put it on the tube that holds the driven plate in place and stops it
from moving so now the pole's ready the plates are fitted we start to string the elements up
so let's start with the 40 meter element and the user guide shows you where to start from basically
opposite the so239 push the element through the first two plates but stop before you go
through the third plate the upper spreader we're going to tension the element here
just to help it stop it waggling around there we are so we need to make a loop with the supplied
glue line heat shrink make a sort of a z shape with the wire and slip the heat shrink from the
very end all the way down over the zed shape and then use a flame or a heat gun to hold that in
place and if you're careful and make this loop neat and tight you will be able to release it
back through the holes when you come to take it apart now we use marine quality four mil four
millimeter what's that just under a quarter of an inch black shock cord from marlow and with some
carabiners and that supports the element to the next available upper spreader you'll find
if you cut the shock cord with some sharp side cutters you'll get a really clean cut and you
can slip the bottom ferrule quite easily over the shock cord don't stretch the cord and then cut it
because what you'll end up is a a slight fraying to the fabric weave just snip it and the ferrule
will go right over the shock cord easily then we make a single overhand knot that's all required
and that will hold that bottom ferrule in place so you can clip the rest of the carabiner together as
a side note we've just started shipping about one meter or three feet more shock cord than
normal in the latest batch there is plenty here now we need to gauge how much shock cord we need
on a per element basis and i recommend you tension this cord to around 90 percent
of its potential tension and it keeps the elements from wobbling about in the wind and i explain this
pretty clearly in the rapide video however in the event you tension the chalk cord extremely tightly
and afterwards you realize you need to shorten the element say by 25 mil or one inch or so on you're
gonna have some wasted cool because the shock cord's not gonna be able to stretch any further
a temporary solution while you build i suggest while you test out your element lengths and tuning
instead connect the shock cord and one carabiner only to the appropriate nylon plate and then
temporarily connect the shock cord to the element loop without a carabiner maybe with a bit of tape
or a small cable tie just to hold it all in place then when it's built you see you can go into the
shack check the tuning make sure you don't need to shorten or lengthen anything and then when you're
happy with the element lengths you can go back out tension the shock cord up stick a carabiner on it
and all's good by the way 40 meters a different matter because as you'll see in a minute
that's easy to lengthen or shorten without any shock cord so you can see i'm judging the length
of this shock cord here then we just continue the 40 meter element up behind the clip and send it
to the top of the pole i do the same loop trick at the little double eye as well just keeps 40
meter happy look at the very top of 40 meters now you can see the element folding back on itself and
this gives you a perfect tune on both 40 meters you see and 15. and you can either do it this way
with the little tubing or some 3m templates here and here's a tip if you want to temporarily fit
any electrical tape leave what i call a field day tail on the tape so you can unwrap the tape easily
later so let's see what we've done all the elements go up through the guide point to
at least a mid-spreader this is where 10 meters and 12 meters stop the rain
railing the remaining elements continue up to the upper spreader is 17 here's 20 meters
some people wonder why the foldback on 20 meters is longer you can see it here it simply means
we've got enough space to connect some shock cord to the upper spreader so it's also easy to shorten
just cut the fold back back we've already looked at 40 here it is again and you can see my
test fit of the 80 meter element going to the little double i i would use the 5 meter point
not this one use that double i for 40 meters and 30 meters only 30 meters if you're not doing
80. you get a choice with this antenna do i go 30 or 80. if you go aging at the atu button you'll
still get 30. this antenna shouldn't need an atu right and another quick look at the top by
the way it doesn't matter if there's not a metal loop here but the expedition model doesn't have a
metal loop just use tape or this tubing which i supply right let's start erecting this pole now
so i make one large step from an imaginary center okay 120 degrees apart where my guy points should
be so that's three guys any metal steak will do you can buy that locally like in a camping shop
or use some cheap angle iron cut the supplied paracord into three equal parts make a little
loop at one end and slip these over the stakes you can see i've already made a little loop in my cord
here about one meter three feet from the guys take that'll come in handy in a minute place all your
cord in the center where the pole's gonna go the completed dx commander isn't heavy simply place
the pole roughly in the center of your guy stakes raise it up you can lean it on your shoulder here
grab a bit of paracord push it up through the holes in the guide point put the paracord through
these larger holes and back down to the little loop then all we need to do is pull upwards
and use it as a two to one pulley you can see me doing it here a couple of simple half hitches will
secure it so you don't need carabiners and stuff here it's actually better in my opinion easier to
use uh just a knotting system i've already laid my radials out this is for a permanent install
i've got a video about those uh radials i'll put that in the description i've also made a
few videos about radials if you're interested i'll put a list of those on in the youtube description
so there's 32 of them here but for holidays i use the same number just 10 feet long three meters in
bunches of four you know six six or so i think i used seven last time once we're all connected
pop back to your shack plug into your radio and test it for a result in most cases you'll just be
happy and start working pile-ups however you may want to adjust some of the elements for a perfect
tune and when i say adjust chances are you're only going to need to adjust it here and you don't need
a complicated analyzer in the main your rig will tell you where the dip is you just go to this page
if you do a google search m0 mcx swr calculator you'll be able to download this excel spreadsheet
and it'll tell you exactly how long or sure you need to adjust your element once you've done that
of course you can head back to the field make the adjustment and then you can tie off appropriately
your carabiners and shock cord it's all done then right i used as an old sailboard or windsurf mast
to support my inverted l interesting tip though a 48 mil scaffold just under two inches scaffold
tube slips inside wins surfing masks but you didn't know that they often come in two sections
so you normally get your seller to to ship it for pennies you know second hand on ebay you know
last tip lots of people are using vaseline to protect against the elements
when it comes to the so239 works for me there are fancy silicon solutions available to wherever so
what have we done i screwed in the bolts on the plates we cut our elements made up our ground
radials we laid the pole down and fitted the plates we strung the elements up and we made
them tight with some shock cord that's it some people like to over complicate it a lot of things
right not me let's just keep it simple but don't take my word for it pop over to eve e ham and read
what other people say or join us on the discord server discord dot io slash dx commander and
join us there all right so enjoy your radio enjoy your antennas i'll see you next time bye for now
really great for them but we have seven grandchildren w1rq