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NQ6U
12-08-2012, 10:26 PM
I'm not a big fan of multi-band HF verticals but when someone offered me an almost-new Cushcraft R-8 for $99 I couldn't pass it up. Seems to get pretty decent reviews and I'll be interested to see if it's an improvement over my too-low 40m dipole.

K7SGJ
12-08-2012, 10:47 PM
I think you will like it. I have a 6BTV that I use when not using the dipole. The noise level seems to be a little higher. It's nice having a. choice in polarity.

VE3FMC
12-09-2012, 08:28 AM
I'm not a big fan of multi-band HF verticals but when someone offered me an almost-new Cushcraft R-8 for $99 I couldn't pass it up. Seems to get pretty decent reviews and I'll be interested to see if it's an improvement over my too-low 40m dipole.

Well the price was sure as hell right! I say you say you have a too low 40 meter dipole. What is too low?

If properly installed the R-8 may give you an advantage when it comes to DX on 40 meters. Again it depends on how low that dipole is.

My 40 meter dipole is only up about 29 feet at the apex and I do ok with it. Sure not as good as I would if it was at 60 feet. But I can work DX on it and it works well for rag chewing within a 500 mile radius of my location.

As K7SGJ noted the noise level may be higher on the vertical. A lot of your local QRN will be more noticeable on the vertical.

NQ6U
12-09-2012, 09:14 AM
Well the price was sure as hell right! I say you say you have a too low 40 meter dipole. What is too low?

It's a flat top at 32 feet, about half the height it ought to be. Don't get me wrong, it does get out, just not as well as I'd like it to. I've worked most of the world, although largely on digital. On phone, I've not done so well.


If properly installed the R-8 may give you an advantage when it comes to DX on 40 meters. Again it depends on how low that dipole is.

On 40m, the takeoff angle from a vertical should be a lower than a half-wave dipole at 32'. At least, that's what I'm hoping for.


As K7SGJ noted the noise level may be higher on the vertical. A lot of your local QRN will be more noticeable on the vertical.

Yes, and I live in an RF-noisy area, which is one of the reasons I'm not a big fan of HF verticals.

NY3V
12-09-2012, 11:33 AM
When I used the free EZNEC Demo, I got a 4 db gain of the low 32' high half wavelength dipole at the 26 degree maximum take-off angle of a ground mounted quarter wavelength Ground Plane and Ground mounted vertical using 7.2 MHz and a high accuracy Real Medium Ground. At 10 degrees TOA, both antennas are equal at -4 dbi gain. At 2% TOA, the vertical would have about 3.5 db gain (about 1/2 S-unit) over the dipole if your Ground was above average.

So, the advantage of a vertical over a dipole at 32 feet is negligible (IMHO).

K7SGJ
12-09-2012, 11:38 AM
When I used the free EZNEC Demo, I got a 4 db gain of the low 32' high half wavelength dipole at the 26 degree maximum take-off angle of a ground mounted quarter wavelength Ground Plane and Ground mounted vertical using 7.2 MHz and a high accuracy Real Medium Ground. At 10 degrees TOA, both antennas are equal at -4 dbi gain. At 2% TOA, the vertical would have about 3.5 db gain (about 1/2 S-unit) over the dipole if your Ground was above average.

So, the advantage of a vertical over a dipole at 32 feet is negligible (IMHO).

It's more difficult to fly a flag from a dipole, though.

NY3V
12-09-2012, 11:42 AM
It's more difficult to fly a flag from a dipole, though.

Not as long as the flag is large enough. ;)

KJ3N
12-09-2012, 09:00 PM
Let me know when the R8 is online, Carl. We'll compare the 2 out to the East Coast on 40m.

X-Rated
12-11-2012, 01:29 PM
The dipole performance is largely defined by the height of the antenna. The performance of the vertical is defined largely defined by the ground conductivity and the radials. We can also say that the height of the antenna has some affect on performance as well due to the decoupling from the ground losses at the higher heights. If you look on the EZNEC, you can change the definition of the ground conductivity and see how this factor can make a lot of difference in the vertical performance. It won't change much on the horizontal performance per a given height. A salt water ground definition is best and sandy soil is worst. For the same take off angle, it is possible to see a difference of 4dB difference between a rich pasture soil and a sandy dry soil. That is a large difference.

kq9j
12-13-2012, 07:54 AM
I have worked more DX with my homebrew vertical for 40 than I ever did on the dipole. Was switching between the two last night. T6LG was coming in rather weakly, I could not hear him on the dipole but I could hear him on the vertical. The more radials I added over the years, the better the vertical performed. It is nice having a choice. Sometimes it makes a big difference.

X-Rated
12-13-2012, 08:27 AM
I have worked more DX with my homebrew vertical for 40 than I ever did on the dipole. Was switching between the two last night. T6LG was coming in rather weakly, I could not hear him on the dipole but I could hear him on the vertical. The more radials I added over the years, the better the vertical performed. It is nice having a choice. Sometimes it makes a big difference.

So many are addicted to the low height dipoles. I am in a DX club here and discussed the higher dipoles with another member. I told him that a 40M dipole on his 70 ft tower would be a bit better than a vertical and he tried it and did very well on a DX contest. People were freaking out because there they believed in verticals on the low bands. But if you can get the dipole up a half wavelength, they become excellent low angle radiators. But, for me, I don't have a 70 ft tower. So I stick with verticals on 40M.

But it is all in what you can do. If you can't get a horizontal antenna up a half wavelength, you should be using verticals.

KJ3N
12-13-2012, 10:21 AM
I have worked more DX with my homebrew vertical for 40 than I ever did on the dipole. Was switching between the two last night. T6LG was coming in rather weakly, I could not hear him on the dipole but I could hear him on the vertical. The more radials I added over the years, the better the vertical performed. It is nice having a choice. Sometimes it makes a big difference.

The first question is, how high is the dipole? Most verticals can out perform a low dipole, for DX.

kq9j
12-14-2012, 06:35 AM
The first question is, how high is the dipole? Most verticals can out perform a low dipole, for DX.

I agree, 100%. My dipole is only about 40 feet high. I found the vertical to be a nice addition to the antenna farm. I like 40 a lot, and would love to put up a yagi. but the tower is too short and not beefy enough to hold a 40 meter beam in addition to the tribander. Unless I could get it up at least 65 to 70 feet, I don't think it would offer much of an advantage over what I have now.

The point is, the majority of hams do not have a 70 foot tower and the vertical offers DX advantages over a low dipole.