5/8 antenna

[918Oklahoma]

Same as the Maco V5/8, less money they tell me:
H&Y - Workman W5/8 Base Antenna

Making antennas that work well is easy, too.

For am inexpensive homebrew read here:

Vertical Sleeved Dipole How To

Same as the Maco V5/8, less money they tell me:
H&Y - Workman W5/8 Base Antenna

Making antennas that work well is easy, too.

For am inexpensive homebrew read here:

Vertical Sleeved Dipole How To

I was looking at the workman but i read some threads about it here and a lot of members were having issues with it. Its hard not to with that kind of price though, wouldnt really be a loss of it broke.

And i actually plan to build a Moxon or Yagi for my horizontal antenna, just want to get a little more familiar with this stuff before i start building one.

I found the Tornado on Sirioantennas.com out of silicone valley, says there are 4 in stock!!
Ordering it now. Thanks for all the help guys.

 

[918Oklahoma]

Oh no! I ordered it and got a receipt for dnjradio.... i guess they run that site as well? Crap... they really need to update their info if they are out of stock, the website says there are 4 available!

 

[magnuman]

I just put up a Sirio tornado.
It works well but don't expect more than a 1mhz bandwidth under 1.5, so your wish for one antenna for 10-11 in the Tornado will not be met without a tuner.
The gainmaster is another animal. it does have a wide bandwidth.

 

[918Oklahoma]

I plan to get an antenna tuner anyway, im going to need one as a ham so thats not an issue... Tornado should work just as well on 10m then.

 

[w9cll]

I plan to get an antenna tuner anyway, im going to need one as a ham so thats not an issue..

No you don't... Resonant antennas, keep telling yourself resonant antennas.

 

[918Oklahoma]

No you don't... Resonant antennas, keep telling yourself resonant antennas.

I guess i dont understand. I thought you needed a tuner to use most antennas on other bands unless you physically tune the antenna by shortening or lengthing it anytime you switch from say 10m to 11m. Or 6m. What are some resonant antennas, you mean like dipoles?

 

[Captain Kilowatt]

No you don't... Resonant antennas, keep telling yourself resonant antennas.

I agree unless he plans to operate the full band on 40m and below. My plan is for resonant antennas for 20m and up and a resonant but narrow band dipole element for about 150 khz of 40m. 80m and below will be resonant antennas but they will not cover the entire bands without a tuner to trim things up a bit.

 

[w9cll]

I guess i dont understand. I thought you needed a tuner to use most antennas on other bands unless you physically tune the antenna by shortening or lengthing it anytime you switch from say 10m to 11m. Or 6m. What are some resonant antennas, you mean like dipoles?

Dipoles, beams, verticals..etc See Ck's comments. A tuner only fools the TX to put out full power but does nothing for the the feed line or antenna. A resonant antenna will always perform better. As CK said, I have a tuner but only for use on a small portion of the band. I have resonant antennas for 15,17,20 and 40 (I rarely use 10 and when I do I will use a tuner there)

I agree unless he plans to operate the full band on 40m and below. My plan is for resonant antennas for 20m and up and a resonant but narrow band dipole element for about 150 khz of 40m. 80m and below will be resonant antennas but they will not cover the entire bands without a tuner to trim things up a bit.

I agree.

 

[918Oklahoma]

Isnt the tornado considered a resonant antenna since its so narrow banded, and wouldnt using a tuner be appropriate for switching between 11 and 10m to trim it up? Im not trying to use it to talk up and down the bands like some do, with the tornado i want it to be strictly for talking on 10 and 11 and thought a tuner wpuld be good for than so im not bringing the antenna down and adjusting anytime i want to work 10m.

 

[The DB]

A tuner only fools the TX to put out full power but does nothing for the the feed line or antenna.

I'm sorry, but this is not true. I suggest reading the works of M. Walter Maxwell, specifically the "Reflections Transmission Lines and Antennas" books , or the freely available .pdf by the same author called "Another look at Reflections". In all of the cases mentioned above chapter 7 is where to look.

A resonant antenna will always perform better. As CK said, I have a tuner but only for use on a small portion of the band. I have resonant antennas for 15,17,20 and 40 (I rarely use 10 and when I do I will use a tuner there)

Now, an antenna tuner is not required on the HF ham bands, no argument there. I can think of several antenna designs that will give you very effective multiband coverage that you can build at home on the cheap and don't require tuners. There are tons of other options to have multiband coverage throughout the ham bands as well. What is best for you depends on what you are trying to do, and what you have to work with.

Using an antenna tuner is but one of them. There are certain cases where using an antenna tuner is a better option. That being said, before you do this you should do some research and ask questions.

Just remember one thing, SWR, in and of itself, is not the cause of loss. The losses are caused elsewhere in the system, and can be controlled and minimized.

And for those who think that a self resonant (there are other forms of resonance) antenna is always the best, tell me, what performs better, a half wavelength antenna or a 5/8 wavelength antenna?


The DB

 

[M0GVZ]

My inverted L which wasn't resonant in any of the ham bands performed exceptionally well despite having a modelled SWR in excess of 85:1 in some cases. Because of its length over a full wave on certain bands, it would have lobes with several dB of gain. Of course that was countered by nulls -30dB or worse but orientated right I could make advantage of those lobes and nulls.

I had no need to worry about feedline losses because I used a SGC230 at the antenna feedpoint so the SWR presented to the coax was always <1.5:1.

When you get to 40m, 80m and top band then only lossy antennas will give full band coverage without a tuner. Even a dipole has only a very narrow range <2:1 on those bands.

Anyway back to the original question posted and my answer is.....NONE OF THEM. The gain from all vertical antennas is quite frankly crap and there's barely half a S point between a 1/4 wave and a vertical dipole, Sirio 827, Gainmaster, whatever. Let the CB mob waste their money looking for a miracle vertical and instead use long recognised antenna theory backed up in practice. Get up a dipole and benefit from the additional ground reflective gain. Have that puppy up at 17ft or more and you're looking at around 4-6dB gain more than any of the verticals you mentioned. Even better, build a Moxon rectangle and use a rotator with it. 100W into one of those puppies even at 16-17ft high will see you working plenty of DX. With one of those at I think it was around 20ft high I did 91 countries in 16hrs one weekend, even working China longpath from the UK with just 100W.

 

[918Oklahoma]

I already have a horizontal 11m dipole up about 20ft.... GREAT for DX. Im wanting the vertical to do some local work, get me on 10m, and give me more omni-directional capabilities because the dipole is definitely showing some directional behavior. I have a lot of trouble working westerly stations with it and am looking for a solution to that.
the moxon or yagi is definitely in my future, however. But i really would like the ability to work stations within a 100 mile radius, with the dipole they cant hear me and i uave trouble hearing them.

 

[HomerBB]

Isnt the tornado considered a resonant antenna since its so narrow banded, and wouldnt using a tuner be appropriate for switching between 11 and 10m to trim it up?

Simple answer:
Resonance is determined by the size/length of an antenna in relation to the wavelength of the band you are working. An antenna can only be resonant within limits. To keep it simple, if your antenna is built to be resonant on 11 meters it will not be resonant on 10 meters. The tuner will help you work 10 meters because it provides a means by which you obtain an impedance match to the radio you are using. The antenna still is not resonant on 10 meters and although workable, is not the same as having a dedicated/resonant antenna for each band.

 

[w9cll]

what performs better, a half wavelength antenna or a 5/8 wavelength antenna?

It would all depend on the what you wanted to do but generally the 5/8 would be better (in theory) but I would rather have a half wave resonant then the 5/8 driven with a tuner.

 

[Captain Kilowatt]

Just a note to throw a wrench into things but the term resonant antennas means the frequency at which the net reactanve is zero and really has nothing to do with SWR. I have used many resonant antennas where the SWR was umpteen to one. Namely various longwires snd an inverted L. The L was resonant on 160m but the impedance was only a few ohms. Let's not confuse the term "resonant " with "perfect match". Resonant dors not mean 50 ohms.