On Mon, 14 Jan 2008 12:49:14 +0000 (UTC), (Geoffrey
S. Mendelson) wrote:

20m would be a good band for me to use, and it will just about fit, so
I was thinking of a 1/4 wavelength radiator with a 1/4 wavelength
counterpoise made out of wire.

Hi Geoff,

I presume by this you mean you have enough, total length, to create a
halfwave dipole for 20M in the conventional sense.

Since I have lots of 300 Ohm twinlead just sitting around, I could
make the radiator out of it. I understand that if I were to short both
ends and center feed it, it would be a standard 300 ohm folded dipole.

To some degree, but that will bring nothing to your advantage.

I think if I were to short the ends and end feed it, it would be a
eaquivalent to a wide(er) 1/4 wavelength end fed antenna and still
need a counterpoise.

Yes, and it brings into doubt my presumption above. It would inform
us all if you gave us the dimensions of your available space.

What would happen if I were to end feed it as if it were two seperate
wires, either with a balun or without? Would it work? What is this called?

An aircooled resistor.

73's
Richard Clark, KB7QHC

Richard Clark wrote:
I presume by this you mean you have enough, total length, to create a
halfwave dipole for 20M in the conventional sense.

No, I don't. I have exactly 25 feet. This needs to include any insulaters
of support ropes at the ends, if I use them.

Yes, and it brings into doubt my presumption above. It would inform
us all if you gave us the dimensions of your available space.

What would happen if I were to end feed it as if it were two seperate
wires, either with a balun or without? Would it work? What is this called?

An aircooled resistor.

Oh, thanks.

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM
IL Voice: (07)-7424-1667 U.S. Voice: 1-215-821-1838
Visit my 'blog at http://geoffstechno.livejournal.com/

On Mon, 14 Jan 2008 15:49:10 +0000 (UTC), (Geoffrey
S. Mendelson) wrote:

Richard Clark wrote:
I presume by this you mean you have enough, total length, to create a
halfwave dipole for 20M in the conventional sense.

No, I don't. I have exactly 25 feet. This needs to include any insulaters
of support ropes at the ends, if I use them.

Hi Geoff,

Put up 3 to 5 sections of twinlead (with the wires shorted at both
ends) on each side, fanned out at the far ends across 3 to 5 feet
(looks like a bowtie). Feed at the apex of each triangular half, that
meet in the middle. Choke the cable feed.

2:1 SWR bandwidth should be at least 1 MHz wide.

73's
Richard Clark, KB7QHC