HAM BIG MAC

[Marconi]

Wonder how that one would work mounted at ground level with ground radials buried?

Mac, here is your idea for the Big Hair on the ground. I can't model radials on the ground, unless I make a free space model. So, I made it 1' foot above the ground.

I also made an overlay with an EFHW at 18' feet as a comparison. The Big Hair looks pretty good still. I haven't tried it at other heights yet, other than the original 36' feet and this one at 1' foot, but this one may not even have to be 36' feet to the base to still work very well compared to some other antennas down low.

View attachment Mac's idea.pdf

Here is an overlay with one of my best models set low to the ground, the Sigma4 at 1' foot high and the BH is still lower in angle and gain.

View attachment Collinear .625w overlay.pdf

 

[gamegetter]

BH's antenna looks pretty thick in the picture. Do you think he also used PVC as the support for the wire?

Here is a modified shape for the stub that performs about like the 6' long stub I started with.

View attachment 7616

Yes he uses pvc to encase the copper wire antenna(s)

On this page: IMAX 2000, Antenna Comparision
He states: "The purpose of this page is to compare my fiberglass C.B. Radio Antennas versus "other" fiberglass 11 meter base Antennas, with an
emphasis on the IMAX 2000. Keep in mind the fiberglass structure itself is not the antenna, but rather the "copper" wire inside the fiberglass
is. The fiberglass simply provides structure support."

 

[Marconi]

Yes he uses pvc to encase the copper wire antenna(s)

On this page: IMAX 2000, Antenna Comparision
He states: "The purpose of this page is to compare my fiberglass C.B. Radio Antennas versus "other" fiberglass 11 meter base Antennas, with an
emphasis on the IMAX 2000. Keep in mind the fiberglass structure itself is not the antenna, but rather the "copper" wire inside the fiberglass
is. The fiberglass simply provides structure support."

That figures since the antenna looked thicker than a very thin wire. My BH models here, are all set with .50" elements so the dimensions would vary accordingly if using wire.

Thanks for the reply.

I guess BM is off busy looking for materials and planning a new antenna model, "The BM-BH MoreBetter cophased 5/8 wave CB vertical."

 

[gamegetter]

he uses from 10 gauge up to 4 gauge wire for the antenna
and from 6 gauge copper wire to 1/2 inch copper tubing for the coil

 

[gamegetter]

Mac, here is your idea for the Big Hair on the ground. I can't model radials on the ground, unless I make a free space model. So, I made it 1' foot above the ground.

I also made an overlay with an EFHW at 18' feet as a comparison. The Big Hair looks pretty good still. I haven't tried it at other heights yet, other than the original 36' feet and this one at 1' foot, but this one may not even have to be 36' feet to the base to still work very well compared to some other antennas down low.

View attachment 7617

Here is an overlay with one of my best models set low to the ground, the Sigma4 at 1' foot high and the BH is still lower in angle and gain.

View attachment 7618

I think it looks better at some height, I wonder if 27 feet would reduce cmc's (if that is what I'm seeing?) as we saw in another model.

At least in this example it seems to give light to the "height is might" slogan...

seems like a combination of elevation and colinearity is potent.

 

[BOOTY MONSTER]

That figures since the antenna looked thicker than a very thin wire. My BH models here, are all set with .50" elements so the dimensions would vary accordingly if using wire.

Thanks for the reply.

I guess BM is off busy looking for materials and planning a new antenna model, "The BM-BH MoreBetter cophased 5/8 wave CB vertical."

LOL , in no way shape or form would i attempt to build that antenna . just thought it was interesting .

btw .... he doesn't use pvc on this antenna , he clearly said fiberglass .

 

[gamegetter]

yeah it's fiberglass...not pvc

but I think Marconi was thinking that the antenna was not encased at all originally.

 

[Marconi]

I think it looks better at some height, I wonder if 27 feet would reduce cmc's (if that is what I'm seeing?) as we saw in another model.

At least in this example it seems to give light to the "height is might" slogan...

seems like a combination of elevation and colinearity is potent.

I agree GG, added height will improve the results and lower the angle. I don't think I've done a model with a mast, so I'm not sure what you saw that indicated CMC for these models. The only way to see CMC in a model is to have a mast/feed line attached. I did the model at 27' as you suggested and I also added a mast, and I saw no significant CMC. The 2 radials seem to be working quite well at decoupling the mast. I'll post the 27' model compared to the 1" models shortly. I'll also add an overlay.

No doubt "height is might" for this collinear design, and it looks to be potent. That is why I posted the overlay of the Sigma4 and the BH at 1' foot elevation for Mac. I was surprised at the results I saw.

Except for the model shown in the linked website, I had no idea what such a model would look like if I did it with the limited information available. The model is close, but I can't duplicate the near field currents pattern in the antenna view, as shown on the link.

 

[gamegetter]

thanks marconi, my bad read on cmc's...

this antenna is interesting to say the least, but just not very practical on the install and as BM was wondering early on, I too wonder how it would hold up to the elements-especially the wind.

Mast mount seems to me to be best mounting.

I never found on the website how much he asks for one of these.