This ham radio coil-loaded 40 and 80 meter inverted V dipole HF wire antenna is easy to build! Loading coils make this antenna a full size on 40 meters and a…
Video Rating: 4 / 5
Doublet aerials for HF amateur ham radio and broadcast bands. A dipole fed with 300 ohm feeder can be used on all short wave bands. If you don’t have Google+…
Video Rating: 4 / 5
Hi Ray……Wouldn’t the formula 468 divided by the frequency of operation
give you a full wave on the frequency….. Isn’t a dipole supposed to be a
half wavelength on the frequency of operation ? Or is this the
difference between a dipole and a doublet ? Of course ignoring all the
other velocity factor calculations etc,,,, either way….as you say…..
it works… so…… Robert is your dad’s brother ..hi..hi..
Hi Ray, love all your videos, also im going to join the radio members area
soon.
Thanks Steve
just gave the Doublet a try, and it was impressive, on all bands from 40 to
10 with 20 is the only band i am not able to load using the MFJ 933B
Ray, appreciate your time on this Video, i saw a design with 300ohm TV line
used as the antenna legs connected at the ends, then also fed with same
line to a tuner, they called for 1/4 wave legs and 1/2 wave feeder length,
what do you think ? I have plenty of this line, and want to take it
portable 80-10 meters, or 40-10 if i have to , Thanks, Aj
Hi Ray.. Good video! Question… If you haven’t a ‘balanced ATU’ and you
need to use coax to connect to the radio, should you use a balun? And
should it be 4:1 or 1:1??? My Yaesu FT920 has an auto ATU and I’d like to
try a doublet!!
Dave
Hi Ray, totally agree about the doublet, I’m in a low rise block of flats
which means an outside aerial is a no-goer. So I have a 66ft doublet up in
the loft, it’s bent into a funny shape but it is symmetrical! The whole
system is homemade including the open wire line and single coil balanced
z-match atu My doublet works great for an internal aerial on all bands from
40m down to 10m on 5 watts qrp!. – But because of it’s shape and the fact
that it’s indoors, if you listen to the “experts” it shouldn’t work at all!
Cheers. Kevin GW4WOV
I’m confused. Wont the 300ohm ribbon pick up a lot of rf noise from the
devices in my house? I’m Using a Grundig 750 radio.
@zerozedzed I took it down today and inspected everything. I checked all
the hardware on the coils and ohmed the coils for continuity. I then
brought them into the shack and measured their inductance. Each one shows
129uh. Great readings on 40 but when I try to shorten the 80 wire to get it
into the phone band, Things go crazy. I am shortening only ONE inch at a
time to be careful. The MFJ shows the frequency moving up but
unfortunately, the SWR is rising and the X is rising.
@zerozedzed Bad LINK. Sorry !
@N6WK Add w w w to the beginning of it. YouTube will not let me post the
actual link. I’ve also added a link to it on the 40/80 antenna project page
on my web site. The other page is mostly pictures but you can probably
email the original author, too. The link to my web site is posted on my
YouTube Channel.
Thanks for a great video. Very informative.. 73 de ve1kev
Yes! 🙂 Diagrams and pictures are posted on my website. The link is at the
top of my YouTube channel and at the end of this video. Thanks for watching
and 73!
Very interesting Dave.Educational indeed.Enjoyed watching this video.Even
in metrical sizes 😉 TNX Regards, Wim.
Thanks Dave for giving me back my confidence after a few failed projects
that cost me good money. Thanks Man: I’ve got the “Bull” by the horns now..
@N6WK This coil is really designed to be used lower in frequency. Try
taking one turn off the coil then check the antenna again. It might take
removing a couple of turns to get it resonate. I should do a another video
for an antenna that works higher in frequency on 80. I’ll probably call it
the “Breakfast Club Special,” hi hi. YouTube is a world wide audience and
so this antenna would appeal to many as it is. I also work lower in
frequency and my phone limit is no lower than 3.600.
hi dave these vids are great i am looking around for some old radios and
collecting stuff for a antenna .very helpful and detailed.thank you
Very, very good. I always enjoy your videos and I ALWAYS learn a lot. 73!
George, N0JRJ
Great Video Dave, But love the tunes with it lol. Keep the great work up
Dave, you have the best instructional videos going. thank you for putting
the effort into it step by step. I have learned so much from you.
Dave, you do a great job of making videos of your efforts. It is very
helpful to anyone interested in Amateur Radio Antenna’s. Keep up the good
work. A lot of people who post assume people watching on you tube have as
much antenna knowledge as they do. Not so all the time. You can impart
your know how without talking down to us Amateurs. Thanks a lot you have
really helped me. James k5gkr
very detailed good work’
73 Ken KB5T
Very we’ll done
Dave, I do appreciate your technisc for making coils. From now on I will
save time and improve my coils. Tnks and 73. PY2CN
Plasti-Dip is also great to coat the coils with.
Dave,
What the heck is all that noise outside… Sounds like locust attacking….
Hey, fantastic job on all your videos.
BUEN PROYECTO , FELICIDADES
Great job whats the power handling ? of that wonderful antenna
How did ya do with the DX window? :)
I followed your helpful construction video exactly and the antenna works
perfectly!! Kudos! Now I’m wondering if I can add a 17 meter element? I
have a feeling that since it doesn’t fall as a harmonic it won’t work well.
-Rick w2JAZ
Dave what is the Wire Dia in mm? Because over in the UK the Wire Sizes are
very different. Many Thanks 2E0PTP
As I am only a General, how is the SWR between 3.850 to 4.000?
Those are amazing SWR’s right out of the workshop!