Hello to all,

I have searched but nothing fits the bill for what I want to do.
Anyways, right now I have a 20m homebrew dipole in my attic at about
20ft. I want to get a 20m wire antenna outside but I live in a condo.
I have, as I see it, two options-

1. Put a vertical dipole from my chimney (35ft) to the ground. I have
a very small patio area so the angle of the wire will be about 70-80
degrees.

2. There is about 100 ft between two unit chimneys. As no antennas
are allowed, however there is a satellite dish at every turn, I would
need to be super stealth and get permission from the neighbors that own
the other chimney (good luck on that), but I could put a dipole between
the two chimneys.

I have looked into a vertical, but I have no room for radials. My
patio is 6 ft deep and maybe 10 ft long.

Any suggestions?

73
Greg
ki4bbl

2. There is about 100 ft between two unit chimneys. As no antennas
are allowed, however there is a satellite dish at every turn, I would
need to be super stealth and get permission from the neighbors that own
the other chimney (good luck on that), but I could put a dipole between
the two chimneys.

I have looked into a vertical, but I have no room for radials. My
patio is 6 ft deep and maybe 10 ft long.

Any suggestions?

73
Greg
ki4bbl

Gregg,

AL7KT, a friend of mine lives in an apartment that forbids antennas.
He has a loop antenna for 80 meters on his roof that goes around four
chimneys. The wire lays on the roof and 300 ohm TV twinlead (low-loss
from rat-shack) comes down the corner and is painted the color of the
apartments. His antenna accidentally fits on 80 meters and dips below
1.5:1 on all but two bands, one WARC. He uses the internal tuner on
his Kenwood TS-440SAT and operates where ever his privileges allow.

His concern is that the wire is literally ON the roof and that instead
of being flat, it has the two inverted vee shapes on the two sides.
The wire is number 14, but it is black and disappears against the dark
gray shingles on the roof. Unless you are looking for it, the 300 ohm
twin lead just disappears due to being painted like the building.

The antenna mostly works well. In only three conversations, his loop
outperformed my 80 and 40 meter sloping dipole hands down, but on 20
meters I was making contacts he couldn't even hear, but then my 20
meter dipole is about 75 feet or so high with one leg slanted upwards
by about 60 degrees or so from there. We live about 10 miles or so in
a crows flight and could barely hear each other on 20 meters. The
little time we spent comparing signals could not be mistaken for being
a valid comparison of antennas, but it did prove his antenna worked.

If you can support and hide your coax from the feed point, you can
consider using magnet wire for the dipole. The wire stretched between
the two chimneys would otherwise go unnoticed. If you need more
strength, you may be able to find some insulated small gauge wire, 18
or smaller, where the color blends into the background and yet the
wire will withstand a little more abuse.

If nothing else, I hope what I said help you get your wheels turning
towards finding you a solution. Good luck


--
73 for now
Buck
N4PGW

Very good idea. I am using a ts-520 with a pi-network so hopefully I
can tune it. I think I will give it a shot. I was worried about
having it lay on the roof, but if experience states it works, I'm up
for it. Ladder line will not work on the 520, but I do have a tuner
that will match it, so I will give it a shot.

73
Greg
ki4bbl

On 25 May 2005 04:56:41 -0700, "Greg"
wrote:

Hello to all,

I have searched but nothing fits the bill for what I want to do.
Anyways, right now I have a 20m homebrew dipole in my attic at about
20ft. I want to get a 20m wire antenna outside but I live in a condo.
I have, as I see it, two options-

1. Put a vertical dipole from my chimney (35ft) to the ground. I have
a very small patio area so the angle of the wire will be about 70-80
degrees.

2. There is about 100 ft between two unit chimneys. As no antennas
are allowed, however there is a satellite dish at every turn, I would
need to be super stealth and get permission from the neighbors that own
the other chimney (good luck on that), but I could put a dipole between
the two chimneys.

I have looked into a vertical, but I have no room for radials. My
patio is 6 ft deep and maybe 10 ft long.

Any suggestions?

73
Greg
ki4bbl

A 20-meter "random wire" I experimented with over the weekend might
work in your setup. It's an end-fed wire -- the Arrl antenna book
recommends an odd number of quarter waves -- I chose three, making the
wire about 49 feet long, attached directly to an "L" antenna tuner in
the shack. I also attached a single elevated quarter wave radial to
the tuner chassis; just ran it out the window and along the house, and
that tamed whatever in-shack rf I had. Got an easy 1:1 match.

If your shack is on the ground floor, such a wire could go straight
up, and then across your roof. Use tiny wire; plastic button
insulators, zig-zag it, etc...

bob
k5qwg

Greg:

If cramped for space with a vertical, you could always use a short whip at
the top and helically wind the rest of the antenna to be one-half wave
electrical length and one-quarter physical length, and using a L-match to
feed it with coax. This would allow you to get by with no groundplane, if
you desired, you could feed it against a small counterpoise...

Warmest regards,
John

"Greg" wrote in message
oups.com...
Hello to all,

I have searched but nothing fits the bill for what I want to do.
Anyways, right now I have a 20m homebrew dipole in my attic at about
20ft. I want to get a 20m wire antenna outside but I live in a condo.
I have, as I see it, two options-

1. Put a vertical dipole from my chimney (35ft) to the ground. I have
a very small patio area so the angle of the wire will be about 70-80
degrees.

2. There is about 100 ft between two unit chimneys. As no antennas
are allowed, however there is a satellite dish at every turn, I would
need to be super stealth and get permission from the neighbors that own
the other chimney (good luck on that), but I could put a dipole between
the two chimneys.

I have looked into a vertical, but I have no room for radials. My
patio is 6 ft deep and maybe 10 ft long.

Any suggestions?

73
Greg
ki4bbl

On 25 May 2005 06:57:21 -0700, "Greg"
wrote:

Very good idea. I am using a ts-520 with a pi-network so hopefully I
can tune it. I think I will give it a shot. I was worried about
having it lay on the roof, but if experience states it works, I'm up
for it. Ladder line will not work on the 520, but I do have a tuner
that will match it, so I will give it a shot.

73
Greg
ki4bbl

Al uses a 1:1 balun (w2au) blows my mind, but it works. I helped him
raise the antenna and check for dips.


--
73 for now
Buck
N4PGW

On 25 May 2005 04:56:41 -0700, "Greg"
wrote:

Hello to all,

I have searched but nothing fits the bill for what I want to do.
Anyways, right now I have a 20m homebrew dipole in my attic at about
20ft. I want to get a 20m wire antenna outside but I live in a condo.
I have, as I see it, two options-

1. Put a vertical dipole from my chimney (35ft) to the ground. I have
a very small patio area so the angle of the wire will be about 70-80
degrees.

2. There is about 100 ft between two unit chimneys. As no antennas
are allowed, however there is a satellite dish at every turn, I would
need to be super stealth and get permission from the neighbors that own
the other chimney (good luck on that), but I could put a dipole between
the two chimneys.

I have looked into a vertical, but I have no room for radials. My
patio is 6 ft deep and maybe 10 ft long.

Any suggestions?

73
Greg
ki4bbl


another thought might be to mount a screwdriver antenna on your
chimney. You will need some form of radial or ground system, but that
might be a multimode solution.

Just a thought, but it is different from what you are asking.

--
73 for now
Buck
N4PGW

On Wed, 25 May 2005 14:34:02 -0400, Buck wrote:

On 25 May 2005 06:57:21 -0700, "Greg"
wrote:

Very good idea. I am using a ts-520 with a pi-network so hopefully I
can tune it. I think I will give it a shot. I was worried about
having it lay on the roof, but if experience states it works, I'm up
for it. Ladder line will not work on the 520, but I do have a tuner
that will match it, so I will give it a shot.

73
Greg
ki4bbl

Al uses a 1:1 balun (w2au) blows my mind, but it works. I helped him
raise the antenna and check for dips.


I just talked to Al, AL7KT on two meters. He says the 75 meter group
which he meets every evening, tell him he sounds like he has an
amplifier. He says that on 80 and 40 it is fantastic.

He says that everyone keeps telling him he is doing it all wrong. The
antenna is allegedly 100 ohms and he is feeding it with 300 ohm tv
twin lead and then a 1:1 balun to a short piece of RG-8 (about 3 feet)
to the rig. We don't know the true length of the loop as we didn't
measure it, we just stretched it out and cut it where it came back
together. We could estimate the length of the wire, I guess, or the
twin-lead.

Oh, also, the twin lead was laying on the ground. He took a staple
gun and stapled it on the side of the building and trimmed off the
excess so it no longer drags the ground. Before doing this, the
antenna only matched two bands, now it matches all but two of the
80-10 meter bands including WARC, but I am not sure if he included 60
meters.



--
73 for now
Buck
N4PGW