now in the last video i showed you the dx commander rapid and how i designed that antenna
in software in this video i'm going to show you how we've built this where you can buy it from
what the swr curves look like how well it operates then we'll go back to the bunker and i'll plot it
out in software and you can work it out whether this is the antenna for you the whole principle
of this is built around six elements on some hexagonal plates each element goes straight up
the pole and to make up the difference between the element and where the next plate is we use marlow
marine quality shock cord and my goodness this will even do cb as well but the surprise to me is
that it gets a perfect tune on the four meter band depending on your country you may have four meters
it works on two i was opening repeaters and i even spoke to a fella mick actually seven miles away
who was using a handy five and five with me on five watts lots coming up stick with the program
but let's start with a build in the kit we've got a seven meter pole we've got some dx10 100 meter
reel 330 feet which we use for both the elements and some small radials okay only three meters
whatever that is in feet 3.2 meters i was using and i've built 24 of those and nice and easily
easy to handle you can get a kit with all the plates so that'll be the ground plate driven plate
guy plate a mid spreader and an upper spreader in that kit also comes with an so239 assembly which
you fit in onto the plate obviously screw all the stainless bolts into the plates you'll find you'll
always get one extra bolt all right and if you don't get an extra bolt it means you've still got
enough use a 10 mil spanner just to tighten them up without stripping the threads that's a set of
forget you'll never need to play with that again because we can then put a washer over the top
and spin a wing nut down for your fork connectors you see you put your radials in there and the
elements i thoroughly recommend you make your elements first i'll show you a cut chart at the
end of this video to show you exactly how long your elements need to be a little tip though
cut them that much too far put your fork connector on put your glue lined heat shrink on i used
some fancy cube markers that i found for kids bracelets i just thought it was cool then once
you've got the fork connector in place measure halfway down the fork connector to the very end
then you can cut it exactly because if you make a bit of a cock-up stripping the wire you're just
cutting into the little bit of spare that you made for yourself at the very beginning i've calculated
on this antenna you put a six centimeter loop six centimeters is that many inches the next bit is to
keep the elements nice and taut we use shock cord four millimeters which is just under a quarter of
an inch you slip over a little ferrule thing put a knot in it so it doesn't come off then you clip
your carabiner together now if it's clipped in together you can go to full stretch on milo
shot chord and it should never come undone i used to say to people don't over tension
your shot chord but marlow's shot called is so nice that i've on mine i have literally gone
to the last there's only about that much tension left they're tight okay i mean they're very
very taut tight whatever you want to say i've tensioned them right up to the sort of max
now once you've got six elements pulling that hard down on the pole it's gonna have
the inclination to collapse what i did is i used one and a half wraps of self-amalgamating tape
on each of the joins and then went twice round with a bit of 3m electrical tape now that's
mine's been up now for over a week under full tension and it's not come down that's that's the
because that you see when you do that it stops water ingress getting inside little beasties
microbiology starting to grow inside that crack and then you get ice water heat and everything
else that will come apart i didn't really come up with this for a true portable solution but
if you're a bit of a caravan or a bit of a camper if you know what i mean and you want it
up for a night it should handle it fine just remember to really pull out each section give it
a really good twist and you'll be fine have some sympathy for the engineering behind this if you
do the shock cord like i did it's going to have a lot of downward force that's all right 30 meters
30 meters goes up to the 5 meter point where the 20 meter element is under tension with shock cord
and you do the same you tension your 30 meter element there with a loop that goes
up and then up again all right then it goes all the way to the top all the way back down
to the upper spreader again with another little bit and then a little bit more shock cord
and to stop the thing floating around the last two sections we supply a little bit of aquarium tube
of different sizes you just slip them over and that will just keep the elements nice and tight
i was very excited because this is my first antenna we've got in the in the new field at
holley farm i was very happy with the 24 radials and back at base after having a twiddle around
with the radio and the uswr meter it's the stick well let's show you the swr curve so on 30 meters
it's negligible 20 meters you can remember 20 meters is quite big so you've got from 14 all the
way up to 14 350 so there's 350 kilohertz you've got to choose your poison here i tuned mine for
14.2 that will still do ft8 but if you want to go all the way down to 1400 you might want to make it
a little bit longer you'll find on my website the swr calculator where you put in what length
your antenna is now and what antenna what length what what length and what frequency your antenna
is now and where you want to aim at and it will tell you whether you want to add a little bit or
take away a little bit so you don't have to do the math yourself that's reliable that's how i
built this antenna because i was off a little bit here and there and i just used my own calculator
to work out whether i needed to cut a bit off 18 is fine 15 is fine 12 is absolutely perfect 10 is
fine you'll notice at the top of 10 the 30 meter element starts working again as a three quarter
wave so you've got this almost flat swr curve from 28.2 ish usable up through 28.5 right up to 29 and
a half now obviously you can move that down 200 kilohertz using the swr calculator that's up to
you if you wanted to do cw and voice for instance six meters the atu button worked and i haven't got
an amplifier for six anyway so it didn't really bother me the swr meter tuned on four meters
so i know some of the uk boys like four meters i got this dude on two as i said it was amazing
and then i had a little play around so i bumped into the first time ever i actually heard someone
on 12 meters well say the first time ages since i've heard anybody on 12 meters now where we're
having a laugh these two guys one was in ireland i can't believe the other guy the other guy was a
papa alpha station i think 10 meters was open last week you probably remember it probably
still is i don't know there was people all over the place there was some local stuff as well
when i say local i mean 100 200 miles stuff going on that was great fun uh you could hardly find a
frequency at some point in time i pumped it to simon g4 tvr who's about 10 miles away
now i'm pleased i was doing 200 watts and he says i'm five nine plus which means the hugging the
low to the ground right that dx capability that i'm after is working in other words my signal
wasn't going straight up all in all a complete success i wonder if i mean i'm not going to get
a tune on 40 meters it's not designed for 40 but i looked at the meter and it was only six to one swr
which is you know fairly high most modern radios will tune six to one swr your atu
button by the way but i did make a contact i heard this guy give him a call and that was fine
and you won't be losing much power at six to one fwr anyway and if you want 40 we got a different
solution for that anyway what you do is you go all the way up to the very top you don't use 30 meters
and you come all the way back down to the guy point that gives you 40 but i haven't done that
yet with the six elements well that'll be five elements won't it because 40 uses up two of them
be assured it will do 40 i know we'll do 40. i just don't know what impact that's going to have
on somewhere around 11 meters it will give us another tune you see all right let's head into
the software now move this out the way this is my little mixing software which a lot of people ask
me what it is it comes with a bearing x air 18. it's not just software you can buy or download
it comes with the mixing desk this is mma and a lot of you will remember me and a lot of you have
come across my channel because of software modeling what i've done in the past reopen
rapid mark one and here it is here i can zoom in a bit you can see i've just built a little
hexagonal plate and you don't need to know how mna m-m-m-a-n-a works the far-field plots are
normally pretty well i haven't found a far-field plot which conflicts with reality anyway let's
just run through the calculations so on one 10.12 as you can see on that swr could it got one point
three four here and as you can see we're getting an absolute perfect quarter wave pattern here
and you'll know from experience if you watched my channel before that at 175 degrees off the horizon
five degrees off the horizon we should be getting about minus five db i'm not going to go into why
i'm into five degrees off the horizon that's a quarter wave any quarter wave will give you about
that depending on the odd soil conditions and and so on so although it sounds a bit cruddy minus 4.9
it says here in the middle of the screen don't be worried about that okay it's just a bass line
just a bass line i've tuned this i think for 2 14 200 that should give us about minus five as well
five minus five point two so we're getting the 17 meter bound as well minus five point three
meters minus 5.2 12 meters 175 minus 5 and 10 meters minus
3.8 slightly better there because with all the other elements interacting with it pushing
the doughnut slightly flatter let's do 145 megahertz um so at five degrees off the horizon
so with six db better than a quarter wave which is why i was hearing mick seven miles away with his
five watt walkie-talkie thing and i was opening all the repeaters it's tremendous you don't want
i mean this is all right at the top here but it's only any ever any good if you wanted to talk to me
the satellites or international space station well there we are the ideal and tailor for you i just
finished recording this video in one take i forgot to show you the 5 8 business with the cb so i've
created a 12 meter quarter wave i've created an 11 meter quarter wave and then for the 30 meter band
i've used that for 10 meters by going up and coming back down a little bit
by coming back down coming back down a little bit more than i've done in the field now and
what that's giving us is a plot on the 12 meter band minus 4.3 at 27.353 say because a lot of
people like to use this on cb we're getting a plot that looks really nice minus 2.4 and then on 28.5
we've got a plot and look at these swr curves here 1.11
it looks a bit of a cloud warmer up here but watch for it down at 175 minus 2.3 so we are in
the main the 10 meter and 11 meter band are about 3 db which is like taking 100 watts and making it
into 200 watts so that's exactly the same on your receive you'll be receiving twice as well as well
so i'm looking forward to putting that hack in i'm also looking forward and wouldn't it be great
if you're not a digital guy you're not into ft8 say on 30 meters you could have a 40 20 17 15.
you would you'd hit your atu button so if you did it this way in fact with your atp
atu button you would get 40 you'd still get 30 because 30 with this new variant is only 3.43
to 1 swr atu button you know 40 30 20. even you get everything you get 12 10 uh 11 6 4 2 and 70.
okay you don't get 80. um well buy some more cake sir
i think this is an antenna for everybody it really is i absolutely it's my favoritest antenna yet buy
one of these so we can carry on eating and paying the rent around here it's coming out 189 pounds
plus 40 pounds shipping to the usa in fact the rest of the world next video to watch is this
one and that's where we designed this in the first place i will see you on the next video bye for now