80m coaxial dipole

[KU0DM]

Here are my plans: Cut a length of RG-59 for 80m and solder the center conductor and shield together on both ends on each length. Then attach the soldered center conductor/shield to coax the way you normally would.

See any problems, would you do anything differently, or do you have a suggestion from experience?

Tnx
--Dunc

[ad4mg]

Here are my plans: Cut a length of RG-59 for 80m and solder the center conductor and shield together on both ends on each length. Then attach the soldered center conductor/shield to coax the way you normally would.

See any problems, would you do anything differently, or do you have a suggestion from experience?

Tnx
--Dunc
I'd have to revisit this in my antenna book, but most coaxial dipoles I've seen lose the outer shield and jacket on the far ends for at least 1/3 of the overall length.

Properly built, I believe coaxial dipoles provide some advantage on the amount of bandwidth.

I really don't know much else about them, but they are quite popular around here for 75/80 meter use!

[KU0DM]

Just dug a little deeper and found my answer, the coax used for the antenna must be the same as the feedline.

Would there be anything stopping me from just taking the braid of the RG-59 and using that as a regular dipole?

[ad4mg]

Just dug a little deeper and found my answer, the coax used for the antenna must be the same as the feedline.

Would there be anything stopping me from just taking the braid of the RG-59 and using that as a regular dipole?
It would stretch like crazy. Let me get a look at the antenna book. It's out in the shack (man cave, some call them "garage"), and I always hit the shack early in the morning.

Nothing beats a cool summer morning in the shack, watching the sun come up. Sometime, I even turn on the radio, but at that hour, I usually just listen, unless a good one pops up on 30 meters. Speaking of, I'll probably hang a 30 meter dipole up this weekend. I may even get ambitious and make it a WARC band fan dipole! I have way too much 12 gauge wire in the shack ... :lol:

[N4VGB]

I helped W4KKO/SK build 2 coaxial dipoles from RG8X many years ago. One for 160 and one for 80. Both worked great for about 5 years and were very broadbanded.

Suddenly both worked sometimes and sometimes went whacky. After lowering both to the ground and doing a little investigation, it was discovered that lightning seems to like dancing back & forth between the center conductor and shield of these antennas, making a mess of the coax.

Solid hard drawn copper wire antennas replaced them and a super duty tuner was added for frequency excursions far from their cut length.

[N2RJ]

You could try RG6 aerial drop cable that the cable company uses. It won't stretch as much.

If you really want bandwidth why not try a cage dipole?

[KJ3N]

If you really want bandwidth why not try a cage dipole?
I prefer 134 feet of wire fed with 450 ohm ladder line directly to a tuner. Barring that, 134 feet of wire fed with 450 ohm ladder line to a 4:1 balun and then to a tuner.

"Bandwidth issue? We don't have no steekin' bandwidth issue!!" :lol:

[n0eq]

Just dug a little deeper and found my answer, the coax used for the antenna must be the same as the feedline.

Would there be anything stopping me from just taking the braid of the RG-59 and using that as a regular dipole?

Coax, any coax, with the braid and center connected at both ends
would simply be a dipole.

Using "just the braid", if removed from the coax (sounds difficult)
would be a simple dipole. It would probably be pretty strong.
It would probably stretch a lot. It would probably have pretty
large bandwidth.

A "bazooka" might be what you're think of experimenting with.
I don't have any personal experience with zook's but it seems
that the comments I've always read are "it's heavy" "it's
broadband" "Did I mention it's heavy?".

Essentially, I'd suggest that if you have no particular need for
wide bandwidth, use easier to deal with wire instead of coax.
If you DO have a need for wide bandwidth, use a cage or other
forms of "more than one wire" instead of the very heavy option
of coax.

Probably the only reasonable use for any coax built dipole that
I can think of would be a temporary field deployed, very durable
antenna that gets put up and taken down very frequently. It
would obviously roll and unroll onto a reel much easier than
most any kind of wire, solid, stranded or braided.

My field deployed antennas (that's virtually all I use) are
17 ga bare copper stranded wire from Home Depot. It costs
30 bucks per 500 ft. Rolls onto reels pretty nicely with the
occasional kink that needs straightening by hand. Doesn't
weigh much at all. Strong enough to function as a guy
as well as the antenna element for inverted Vs. Use
parachute cord for the tie off's.

Photos and descriptions of the above style antenna(s) at -
http://www.digitalcartography.com/n0eq/snorkel.htm


Craig 'Lumpy' Lemke

http://www.n0eq.com

[ad4mg]

If you really want bandwidth why not try a cage dipole?
I prefer 134 feet of wire fed with 450 ohm ladder line directly to a tuner. Barring that, 134 feet of wire fed with 450 ohm ladder line to a 4:1 balun and then to a tuner.

"Bandwidth issue? We don't have no steekin' bandwidth issue!!" :lol:
Yep! Doesn't get any simpler or better than that!

[N2RJ]

If you really want bandwidth why not try a cage dipole?
I prefer 134 feet of wire fed with 450 ohm ladder line directly to a tuner. Barring that, 134 feet of wire fed with 450 ohm ladder line to a 4:1 balun and then to a tuner.

"Bandwidth issue? We don't have no steekin' bandwidth issue!!" :lol:

I have one of those, works pretty well.

[kf4jqd]

Almost sounds like a bazooka antenna! :spin:

Andy KF4JQD