right so tom's going away on his trip in three weeks time he's actually on
the camera thank you tom no worries there's a noise outside like a bloody
bumblebee going off but anyway if we can ignore that ladies and gentlemen
we're going to do a linear loaded 80 meter dipole so let me explain what linear loaded is come with
me you know we have our coax coming up to here we have the braid going one way in the center going
the other way and a dipole for 80 meters will normally have roughly a leg of about 19.5 meters
depends on the height on the ground the lower it comes to ground the shorter this can be now we're
linear loading it so we're going to go there and come back okay so that's what we're doing
we've calculated that this will be a maximum of 14 meters long which is getting on for 50 feet
maximum each side so that's what we're doing we've got a little calculator which we put together it's
over here so years ago we had a 6.8 meter pole and i went up and came back down and i was resonant on
around 7.6 megahertz extrapolating that out i know if i go 14 meters we should end up around about
3.6 3.7 but we can trim to suit all right so this is dx10 now dx10 doesn't come like this this is
a really old we used to reel them off years ago on huge great drums they now come on reels like
this but since we've got some of this knocking around i thought we'd use it up 14 meters okay
about there i reckon then i'll find the end
so it's 14 114 back so we need 28 actually don't we so that's 14 there
so what i'll do now is i'll put a fold there
this end up might be permanent so or put some heat shrink on there probably
right now i need another 14 so
incidentally i've changed hands so that the the induced turns i'm putting on there i'm doing an
anti-induction here how about that but seriously that will work
i'm taking the twist out basically now tom has got the option he could have two 90 meter legs
but we'll see how cumbersome this is oh you're on it
and if it's easy to manage then presumably might keep it we've got one of these which
is a water jet cut uhm wpe plate and we'll we'll come up with a little system
where is we'll put some coax on here we'll sold all this self-amalgamate it he'll come down to a
little pigtail so that's his center i'm going to get rid of this over here now okay so there's one
now tom yep do i use this as the measuring stick but then we got wire everywhere
i've got 14 already marked out here so let's just do it on this so we have another
i don't know if i've got 28 on here
i don't know i'm gonna we'll just put a few on shall we see it's just to hold it all together
isn't it i haven't counted i don't know how many we've done we'll work it out in a minute
so tom's doing at the moment he's just
checking because we found an old patch lead with a connector on it we'll put a
bullet on the end he's just checking it's not shorted and it works and everything
seems to be working lovely good i'll
yeah and how far do we want to come back though our elements are going to come along we're going
to go around twist and they'll be floating around about here so the end of this probably needs to be
all right then i'll strip that back and then we'll have the center yeah from about there
upwards lovely i think i need some more heat sheet but i don't know where to get it from
let me go and discover why
you got the red dot going yes the red dot is going excellent
let me put this back otherwise i might get told off
if this turns out to be too heavy well we'll just dump it and come up with another solution tom okay
and backwards that leg goes that way that leg goes that way and it is there is another bit to it
uh where's your coax
right
just to hold it in place for a bit shall we
oh a bit of heat shrink there a bit of heat shrink there
now
okay so that's one side that's the other
so in fact that one can come off
in favor of two of one of these i've got too many cable ties
i don't want to overboard it hmm in case you need to re-engineer it when you're out
in the middle of nowhere or something but you'll have we'll give you a roller tape
just hold that together nicely
uh where's that bullet
i thought i'd put it down did you pick it up no there it is we'll convert it into
so239 all right so we've got it up here what height is that uh tom three three and a half
meters it's about ten eleven feet that's the american yeah and then we got each leg so tom's
gone one leg all the way down there all the way down that way yeah and then the other leg
um interesting enough at the bottom of the ssb portion of the band which is about 3.6
cw's down here somewhere but let's say 3.6 we've got an swr of well it's almost a perfect match
so we need to go from 3.6 to about 3.7 and incidentally before we started this i
guessed that the percentage length of a linear loaded element was about 17.2
it's actually if it's fully low loaded it's about 16.7 percent so we need to come up from 3602
and we need to come up to about 3.7 3.75 i calculate roughly with a bit of funny mass that's
probably a meter and a half off one of both of the legs all right not a meter and a half off the
whole linear loaded length what we're going to do is to fold back we're going to come back a meter
and a half that's all we're going to do all right so we'll go back out film that and see how we get
on 3.6 so what we're going to do now is i'm going to we're going to take this down so i can get to
it i'm going to go back to the center we're gonna take off one and a half meters off the return bit
right so all we need to do is take a meter after i'm gonna guess that i'm gonna
i'm gonna say that it's that much all right that's what we're gonna do and i'll do the same on both
oh no i'm bleeding some people don't like it when i do this they get all squeamish
at home you know when i start cutting my fingers and everything bleeding and bleeding yeah yeah
i try not to bleed too much on camera you know i don't think it's good for the children
this is this is a children's channel you know okay so i said about a metre and a half
about so let's go about a meter half which i reckon it is
if i do the same on both that's there isn't it oh tom i just saw we don't oh
now i've got to cut the right one tom we can't cut the wrong one can we
well you wouldn't catch me doing that no but we can't have that hanging down i need a bit of tape
don't tell me you've got some tape
well i'll do the other way tom's got the tape
that's must be in the military to be able to just rustle things like that
what i'll do is i'll fade this to black and white so you don't have to look at my bleeding finger
so that's one side
we thought actually what we could do is wrap a bit of insulation tape around my finger in fact
it was tom's idea but being a surgeon you know he's going to think of things like that hasn't he
right so now you don't have to look at the blood color can come back now okay bring on the color
this is a brand new bloody knife as well so we're going for take two on the cut finger
now we're with this right we end up with two cut fingers but i'm just going gentle so this is glue
lined heat shrink it does come off with a little bit of teasing basically there you go lovely
meter and a half that much
hey
i need a handbag
okay
now after all this tom and i have of the opinion that to go backpacking with a full-size dipole
even though it is linear loaded it's slightly crazy might be a bit of a big ask but anyway
all right we'll string this back up and we will see you back in the shack right we've overshot by
basically every 10 centimeters which is four inches five inches 10 centimeters look it up
um is 10 kilohertz as it turns out so we took 1.5 meters off and it was about 150 kilohertz so um
yeah anyway we're just going to add a little bit back in so we'll do that come back in here
and see where it tunes out let's see hello mike zero x-ray x-ray tango cq cq over here
uh roger roger who's that then
just a minute i'm just gonna read a second i'm just gonna reach him okay then sorry about
that i was tuned for seven to eight seven legs 40 meters like zero x-ray x-ray tango good afternoon
my name is david and the call is mike zero indian oscar very good afternoon this is m0xxt
queen
so um that works okay we got it down to uh where was it about one point three one point
four to one i think on average for about 50 kilos that'll be fine for tom if he takes it
away if not i think we'll just use it here or i'll take it away on holiday so linear loading
it's a cool experiment suggest you get on with it and give it a go it's an idea if you've got
a small garden you're trying to maybe get on 160 you could maybe do a bit of a you could form it
into a bit of a halo who knows next video is coming up here but in the meantime thanks for
tuning in and we will see you on the next one okay all the best now bye-bye what is it um
carl just why is that red light that's one of my next 30 issues