New Top One dimensions for Homer

[Marconi]

Homer, I couldn't find you email address in my address book, so here are the dimensions close to what I measured on my New Top One. The values from Sirio are metric, but I did my model in inches.

View attachment New Top One.pdf

 

[HomerBB]

Thanks!
This will do.

 

[HomerBB]

They are virtually identical to the lower section and gamma of the V4k.
We'll see . . .

 

[Marconi]

They are virtually identical to the lower section and gamma of the V4k.
We'll see . . .

You may be right. I recall that Bob did the same as you're suggesting, but he used an old Vector...and he told me he was not resonant because his V4000 did not have 107" long radials.

Good luck.

 

[HomerBB]

Mine are 106.5" I think. If not, they have this:

Adjust-ability -

 

[Marconi]

That's good. I don't think the Sirio NV4K is adjustable at that point...without modifying the radials some.

 

[HomerBB]

I got the radials and gamma reversed to each other, and isolated the radials form the center vertical.
I do not have the cap hat made, yet, so it is extended to around 87.5".
I ran out of time this evening so haven't tuned it or anything.

 

[HomerBB]

A friend came by after work today for a visit. He took my homebrew Astroplane with him. However, that left me with limited time to attempt to tune the NTO without the Cap Hat. I felt I had gotten to resonance with the length adjusted to 89.5" from the radials hub upward. I began to try to draw the SWR/tune down from 1.2:1 when the jumper I was using decided to ground out on me. I need to make a brand new one. I'll have to get back to it later. The SWR in the shack is flat on 27.385, but we shall see what it looks like with the analyzer after the weather clears back up . . .

 

[Marconi]

IMO the New Top One design/function is very similar to a yagi driven element using plumbers delight and a gamma to feed.

BTW, I got a PM from you that was noted as unauthorized and that the text had been moderated. I don't know why that happened that way...do you? Your PM I received the other day was OK.

 

[HomerBB]

Yep. With the radials grounded to the vertical it would be similar to the gamma matched driven element of A Yagi.

I need to go back to the antenna and remove the insulator from between the radials and the vertical. When I put it in there I was only thinking like the customary way radials are isolated. After I got it done and in the air I began to doubt it should have been done as it made no sense. This will expedite the tune up tremendously, I think. Expecting rain tonight and tomorrow, but perhaps it will all be gone by early afternoon so I can get that redone quickly.

I got your answer, but have no idea why it was moderated. It said it was an unapproved visitor message???

In another NTO thread two questions were asked specifically of Marconi - . . . NTO review . . .

 

[HomerBB]

I tried to get a little more done today, but it wasn't in the stars. The wind was horrific. I nearly lost the antenna trying to hoist it up onto the mast and was going to quit until the wind momentarily abated so I could try again. Well, that was it. The wind renewed its vendetta against my antenna play and drove me off the roof.
Later.

OTOH, I did key up a few times with it and spoke to a contact in Oregon, and to Stan, 17WR396, on the Big Island, HA. So it works, but isn't tuned exactly where I want it to be. The SWR meter shows it to be good at the shack end of the coax, but I am wanting it to be as good with the analyzer at the antenna end of the coax as it can be.

 

[Marconi]

I tried to get a little more done today, but it wasn't in the stars. The wind was horrific. I nearly lost the antenna trying to hoist it up onto the mast and was going to quit until the wind momentarily abated so I could try again. Well, that was it. The wind renewed its vendetta against my antenna play and drove me off the roof.
Later.

OTOH, I did key up a few times with it and spoke to a contact in Oregon, and to Stan, 17WR396, on the Big Island, HA. So it works, but isn't tuned exactly where I want it to be. The SWR meter shows it to be good at the shack end of the coax, but I am wanting it to be as good with the analyzer at the antenna end of the coax as it can be.

Homer, maybe I shouldn't ask, but is what you did above...before or after your reconnected your radials to the antenna?

Since I might be the only one around that will talk to you about the New Top One or the AstroPlane...can I ask some questions?

 

[HomerBB]

After I reconnected the radials to the vertical.
Go ahead with the questions.

 

[Marconi]

I got the radials and gamma reversed to each other, and isolated the radials form the center vertical.
I do not have the cap hat made, yet, so it is extended to around 87.5".
I ran out of time this evening so haven't tuned it or anything.

I did not respond to your post above because it confused me. When I read it I was curious why you had the notion to isolated the radials if you were using a gamma.

Didn't you tell us you checked the match with the setup above and you got 1.2:1 SWR?

I wonder how that setup would work using a gamma and isolating the radials?

You also noted that you had not yet made a top hat and instead you extended the radiator out to a full 1/4 wavelength at 87.5" in the beginning. Then later you said the radiator was 89.5" inches.

My notes indicate that I found 87.5" inches was resonant at 27.205 mhz using the original A/P 47" x 3/4" base radiator and the top element of my Sigma 4 at 45" x 1/2" inches. I would like to confirm my findings if you can help.

What diameter tubing did you use for your radiator?

Thanks,



Keep us posted on your progress.

I also talked to some guy in Hawaii on my Starduster yesterday afternoon late.

 

[hotrod]

After I reconnected the radials to the vertical.
Go ahead with the questions.

i would like your opinion on the performance locally on the NTO verus the old astroplane