I have installed a inverted V wire antenna. I have it connected with a
1:1 balun at 30 feet from the ground. The center wire is 66 ft 6 in
long. The end is 8 feet from ground. The other leg is 28 ft long and
attached to the roof of my house (appox 20 feet). I am getting started
in MARS and need to transmit around 3.350 MHZ. What can I do to this
antenna to tx around that freq ? Right now the antenna works from 40
meters to 6 meters with my MFJ 945 tuner. I was thinking I could make a
wire trap for it. Thanks for any ideas.
"73"
Tim

Tim Boyd said :

I have installed a inverted V wire antenna. I have it connected with a
1:1 balun at 30 feet from the ground. The center wire is 66 ft 6 long
snip
Right now the antenna works from 40 meters to 6 meters
snip
I am getting started in MARS and need to transmit around 3.350 MHZ

You just said it above...your antenna is ~66 feet in length, about
right for 40 metres. If you need to transmit around 3.5 MHz, you will
need to double the size of the antenna at the very least. You will
probably need somewhere around 128 feet of antenna, though it varies a
little depending on numerous factors specific to your installation.

However...

The end is 8 feet from ground.

That's another problem entirely. The idea is to keep your antenna
roughly 1/4 wavelength above terra-firma. Easy to do at 20 metres,
harder at 40 and very hard to do at 80. My own 80M dipole is only
about 45 feet above ground level and even with 600W, getting a signal
out is a chore at times on that band. If you can, you would do very
well to get the entire thing up as high as you can.

You may also face space problems with an antenna of that length. If
your property size won't allow you to put up a high 128'-foot-long
antenna, there are electrically shortened antennae out there that
might work acceptably for you, but will offer you greatly reduced
bandwidth. If you're also a licensed amateur in addition to MARS
operator, and you want to use that antenna for 75M phone, you'd have a
problem with one of these shortened dipoles.

Good luck.

73 de Peter, W2IRT
(ex-AB2NZ, VE3THX)

Please reply to Double-you Two Eye Are Tee at Arrl.net

Tim Boyd said :

I have installed a inverted V wire antenna. I have it connected with a
1:1 balun at 30 feet from the ground. The center wire is 66 ft 6 long
snip
Right now the antenna works from 40 meters to 6 meters
snip
I am getting started in MARS and need to transmit around 3.350 MHZ

You just said it above...your antenna is ~66 feet in length, about
right for 40 metres. If you need to transmit around 3.5 MHz, you will
need to double the size of the antenna at the very least. You will
probably need somewhere around 128 feet of antenna, though it varies a
little depending on numerous factors specific to your installation.

However...

The end is 8 feet from ground.

That's another problem entirely. The idea is to keep your antenna
roughly 1/4 wavelength above terra-firma. Easy to do at 20 metres,
harder at 40 and very hard to do at 80. My own 80M dipole is only
about 45 feet above ground level and even with 600W, getting a signal
out is a chore at times on that band. If you can, you would do very
well to get the entire thing up as high as you can.

You may also face space problems with an antenna of that length. If
your property size won't allow you to put up a high 128'-foot-long
antenna, there are electrically shortened antennae out there that
might work acceptably for you, but will offer you greatly reduced
bandwidth. If you're also a licensed amateur in addition to MARS
operator, and you want to use that antenna for 75M phone, you'd have a
problem with one of these shortened dipoles.

Good luck.

73 de Peter, W2IRT
(ex-AB2NZ, VE3THX)

Please reply to Double-you Two Eye Are Tee at Arrl.net

On 19 Aug 2004 06:09:08 -0500, Peter Dougherty
wrote:

Tim Boyd said :

I have installed a inverted V wire antenna. I have it connected with a
1:1 balun at 30 feet from the ground. The center wire is 66 ft 6 long
snip
Right now the antenna works from 40 meters to 6 meters
snip
I am getting started in MARS and need to transmit around 3.350 MHZ

You just said it above...your antenna is ~66 feet in length, about
right for 40 metres. If you need to transmit around 3.5 MHz, you will
need to double the size of the antenna at the very least.

Key word: Center Wire.

"The other leg is 28 ft long and attached to the roof of my house
(appox 20 feet)".

I'm assuming the "center" wire is the center wire cuz it's hooked
to the center conducter of the coax? If that's the case, he doesn't
have a "dipole". He has what is closer to a Windom, with a 1:1 balun
(which doesn't work, on most Windoms anyway).

But you're right - if he's trying to make a Windom, and he wants
it to work on 80 meters, it's going to have to be at least as long
as an 80 meter dipole.

Then he's gonna have to lose the 1:1 balun and get a 4:1 balun,
and then he's gonna have to lose the tuner......

So I think the technical name of what he has now would probably
be "An Off Center Feed Dipole With A 1:1 Balun That's Really A
Dummy Load But It Works OK Until The MFJ Tuner Melts Or The
Balun Saturates". Or something like that :-)

Here's a picture of a Windom, Tim.

http://kh2d.net/windom.cfm

It presents a decent SWR on 80 meters, but at 30 feet high it's
virtually useless as an antenna on that band.

You'd probably be better off with a center fed dipole, cut to the
frequency you want to operate on, if you can't get it any higher
than 30 feet up.

73, Jim KH2D

On 19 Aug 2004 06:09:08 -0500, Peter Dougherty
wrote:

Tim Boyd said :

I have installed a inverted V wire antenna. I have it connected with a
1:1 balun at 30 feet from the ground. The center wire is 66 ft 6 long
snip
Right now the antenna works from 40 meters to 6 meters
snip
I am getting started in MARS and need to transmit around 3.350 MHZ

You just said it above...your antenna is ~66 feet in length, about
right for 40 metres. If you need to transmit around 3.5 MHz, you will
need to double the size of the antenna at the very least.

Key word: Center Wire.

"The other leg is 28 ft long and attached to the roof of my house
(appox 20 feet)".

I'm assuming the "center" wire is the center wire cuz it's hooked
to the center conducter of the coax? If that's the case, he doesn't
have a "dipole". He has what is closer to a Windom, with a 1:1 balun
(which doesn't work, on most Windoms anyway).

But you're right - if he's trying to make a Windom, and he wants
it to work on 80 meters, it's going to have to be at least as long
as an 80 meter dipole.

Then he's gonna have to lose the 1:1 balun and get a 4:1 balun,
and then he's gonna have to lose the tuner......

So I think the technical name of what he has now would probably
be "An Off Center Feed Dipole With A 1:1 Balun That's Really A
Dummy Load But It Works OK Until The MFJ Tuner Melts Or The
Balun Saturates". Or something like that :-)

Here's a picture of a Windom, Tim.

http://kh2d.net/windom.cfm

It presents a decent SWR on 80 meters, but at 30 feet high it's
virtually useless as an antenna on that band.

You'd probably be better off with a center fed dipole, cut to the
frequency you want to operate on, if you can't get it any higher
than 30 feet up.

73, Jim KH2D

I have been using antenna's fed with ladder line recently and I have had a
lot of success.
You will need to get a different tuner, a tuner that accepts balanced line
such as ladder line. There are some good ones out there but they arent exactly
cheap.
I am using the MFJ-986.
(this tuner also accepts coax as well)...
With the ladder line and tuner you do not need to worry about SWR or the coax
loss with high swr.

You can try this antenna with your coax and your tuner right now and it
might work better.

You could put up something like a 40 meter 1/2 wave sloper. Just a wire
about 65' long (468/freq in mhz), going from your support at 33' down to your
lower support. Then just use an egg insulator and connect one end of the coax
to one side and the braid of the coax to the other side (or the ladder line
like this).
Make sure the connections are soldered good.
This antenna should work very well on 40 meters and with your current tuner
it should work okay for 80 meters. At least stateside if the tuner can handle
it.

The ladder line would tune this fine with a different tuner.

But this would be a fine dipole on 40m and other bands with the tuner. its
worth a try I think.

Another antenna I have used on 80 and other bands is a 1/4 wave inverted L.
Yours would be a little short and sloping, but take a wire up your 33'
support and then down to your lower support. This would be almost 100' about
23' short of a 1/4 wave on 80m but the tuner will help.
Connect the center wire of your coax to this wire and the braid of the coax
to a ground rod and a radial system. You will need to lay down some radials in
your yard for this antenna. Whether it was fed with coax or ladder line. But
either feedline with a tuner should work pretty good on 80M.

73
Craig
N0BSA


I have installed a inverted V wire antenna. I have it connected with a
1:1 balun at 30 feet from the ground. The center wire is 66 ft 6 in
long. The end is 8 feet from ground. The other leg is 28 ft long and
attached to the roof of my house (appox 20 feet). I am getting started
in MARS and need to transmit around 3.350 MHZ. What can I do to this
antenna to tx around that freq ? Right now the antenna works from 40
meters to 6 meters with my MFJ 945 tuner. I was thinking I could make a
wire trap for it. Thanks for any ideas.
"73"
Tim

I have been using antenna's fed with ladder line recently and I have had a
lot of success.
You will need to get a different tuner, a tuner that accepts balanced line
such as ladder line. There are some good ones out there but they arent exactly
cheap.
I am using the MFJ-986.
(this tuner also accepts coax as well)...
With the ladder line and tuner you do not need to worry about SWR or the coax
loss with high swr.

You can try this antenna with your coax and your tuner right now and it
might work better.

You could put up something like a 40 meter 1/2 wave sloper. Just a wire
about 65' long (468/freq in mhz), going from your support at 33' down to your
lower support. Then just use an egg insulator and connect one end of the coax
to one side and the braid of the coax to the other side (or the ladder line
like this).
Make sure the connections are soldered good.
This antenna should work very well on 40 meters and with your current tuner
it should work okay for 80 meters. At least stateside if the tuner can handle
it.

The ladder line would tune this fine with a different tuner.

But this would be a fine dipole on 40m and other bands with the tuner. its
worth a try I think.

Another antenna I have used on 80 and other bands is a 1/4 wave inverted L.
Yours would be a little short and sloping, but take a wire up your 33'
support and then down to your lower support. This would be almost 100' about
23' short of a 1/4 wave on 80m but the tuner will help.
Connect the center wire of your coax to this wire and the braid of the coax
to a ground rod and a radial system. You will need to lay down some radials in
your yard for this antenna. Whether it was fed with coax or ladder line. But
either feedline with a tuner should work pretty good on 80M.

73
Craig
N0BSA


I have installed a inverted V wire antenna. I have it connected with a
1:1 balun at 30 feet from the ground. The center wire is 66 ft 6 in
long. The end is 8 feet from ground. The other leg is 28 ft long and
attached to the roof of my house (appox 20 feet). I am getting started
in MARS and need to transmit around 3.350 MHZ. What can I do to this
antenna to tx around that freq ? Right now the antenna works from 40
meters to 6 meters with my MFJ 945 tuner. I was thinking I could make a
wire trap for it. Thanks for any ideas.
"73"
Tim