Loop Antennas
 

On Tue, 8 Nov 2005 13:51:06 -0800, "Michael" wrote:

I get a lot of noise from my random wire antenna. It transmits very well but
is very noisy in receive. My neighbor put up a 280 foot loop antenna which

Ok.

he feeds with ladder line. He feeds the ladder line from a 4 to 1 balun to
coax. The coax comes from a tuner. His setup performs very well on all bands
down to 75 meters. I went over to his shack last night and listened to his
receiver on 75. I was really impressed with the lack of noise. I can safely
say the difference in noise was profound. He has this loop surrounding his

So, the noise is "profoundly" less (whatever that means), but what
about signals that you want to hear, and how does it perform
transmitting.

You see, a 30dB attenuator would profoundly reduce the noise.... and
the desired receive signals, and the tx signal, but it isn't
necessarily better.

You probably know the answers, you just didn't tell us.

It is often the case that the best antenna for transmission is the one
that makes the most noise where you want to be heard, and the best
antenna for receiving is the one that gives the best S/N ratio (not
necessarily the best S meter deflection) for stations from that place,
and they may not be the same antenna.

Owen
--

Loop Antennas
 

Michael wrote:
Has anybody else had this experience with loops?

Only the past three generations. :-)
--
73, Cecil http://www.qsl.net/w5dxp

Loop Antennas
 

Ah yes grasshopper - zee loops - zay are good.
The loop helps reduce noise since its dc-shorted and no static buildup,
and your socks won't stick to it. ;-)
but it takes more trees to hold it up


"Michael" wrote in message
...
I get a lot of noise from my random wire antenna. It transmits very well
but
is very noisy in receive. My neighbor put up a 280 foot loop antenna which
he feeds with ladder line. He feeds the ladder line from a 4 to 1 balun to
coax. The coax comes from a tuner. His setup performs very well on all
bands
down to 75 meters. I went over to his shack last night and listened to his
receiver on 75. I was really impressed with the lack of noise. I can
safely
say the difference in noise was profound. He has this loop surrounding his
house at a 30 ft. height. It is arranged in a square.

Has anybody else had this experience with loops? It looks like I have room
to put up a triangular loop. Will this work as well?

Can I use the same tuner I have now and just feed a coax into a balun. Or,
should I put the balun in the tuner and come straight out with ladder
line?
There is a lot of room in this tuner. It is an old remote controlled tuner
surplused from a ship.

Loop Antennas
 

Michael,
I've had sort of the same experience with a loop antenna. I'd say
it was probably about the same for most everyone.
As far as where to put the balun and how to feed the thing, I
honestly don't think it's going to make much difference. What would be
easiest and 'best' for you? That's how I'd do it...
'Doc

PS - Are loops the 'end-all of antennas? Huh, good question, and the
answer is probably, no. But, I've had good luck with mine...

Loop Antennas
 

On 2005-11-08, Michael wrote:

Has anybody else had this experience with loops? It looks like I have room
to put up a triangular loop. Will this work as well?

Can I use the same tuner I have now and just feed a coax into a balun. Or,
should I put the balun in the tuner and come straight out with ladder line?

Following Walt's (W2DU) ideas, I have a 259' horizontal delta (triangle)
loop (two trees and a wooden pole) fed at almost middle of one side
(convenience, not design) by 450 ohm ladder line. This is soldered directly
to a ferrite bead choke balun (ala W2DU) which, via PL-259s and barrel
connector, goes to a very short piece of 50 ohm coax (about 6') directly
into the house to the unbalanced SO-239 input of my MFJ-941E. Works like a
charm on all bands 80-10m, no RF in the room, and good signal reports.

....Edwin, KD5ZLB
--
__________________________________________________ _____
"Once you have flown, you will walk the earth with your
eyes turned skyward, for there you have been, there you
long to return."-- da Vinci ... www.shreve.net/~elj

Loop Antennas
 

Michael.
Why not try a folded dipole made from 300 ohm TV twin lead? Cut it for
the band you are interested in. A tuner or a balun to 52 ohm coax to
match your rig will be necessary. I was impressed with the lack of
noise pickup from the one I put up a couple of years ago. Cut for 75
meters. My home and antenna are just a hundred feet or so from a power
line with 3 sets of high voltage lines and sometimes they are very
noisy on a regular dipole, but not the folded dipole.

Paul, KD7HB

Loop Antennas
 

I get a lot of noise from my random wire antenna. It transmits very well but
is very noisy in receive. My neighbor put up a 280 foot loop antenna which
he feeds with ladder line. He feeds the ladder line from a 4 to 1 balun to
coax. The coax comes from a tuner. His setup performs very well on all bands
down to 75 meters. I went over to his shack last night and listened to his
receiver on 75. I was really impressed with the lack of noise. I can safely
say the difference in noise was profound. He has this loop surrounding his
house at a 30 ft. height. It is arranged in a square.

Has anybody else had this experience with loops? It looks like I have room
to put up a triangular loop. Will this work as well?

Can I use the same tuner I have now and just feed a coax into a balun. Or,
should I put the balun in the tuner and come straight out with ladder line?
There is a lot of room in this tuner. It is an old remote controlled tuner
surplused from a ship.

Loop Antennas
 

"I get a lot of noise from my random wire antenna. It transmits very well
but
is very noisy in receive. My neighbor put up a 280 foot loop antenna which

Ok.

he feeds with ladder line. He feeds the ladder line from a 4 to 1 balun to
coax. The coax comes from a tuner. His setup performs very well on all
bands
down to 75 meters. I went over to his shack last night and listened to his
receiver on 75. I was really impressed with the lack of noise. I can
safely
say the difference in noise was profound. He has this loop surrounding his

So, the noise is "profoundly" less (whatever that means), but what
about signals that you want to hear, and how does it perform
transmitting.

Well, I would not be raving about his antenna if it also reduced the signals
you want to hear. He gets the same kind of signal reports that I do. We were
both on the same net one night and we were both be received equally at
various spots. Clearly, mine transmits as well as his.

You see, a 30dB attenuator would profoundly reduce the noise.... and
the desired receive signals, and the tx signal, but it isn't
necessarily better.

When I listened to our local North Dakota Data Net, I heard all the checkins
like they were much much closer. No Noise! I should have been more specific.
The S?n ratio was profoundly better than my puny random wire. However, I do
not know yet if I am up to putting up 3 or 4 32 foot poles or higher. What a
drag. I will probably do this next spring. It is getting too cold to make
the task a very pleasant one now.

You probably know the answers, you just didn't tell us.

It is often the case that the best antenna for transmission is the one
that makes the most noise where you want to be heard, and the best
antenna for receiving is the one that gives the best S/N ratio (not
necessarily the best S meter deflection) for stations from that place,
and they may not be the same antenna.

Owen
--

Loop Antennas
 

"Hal Rosser" wrote in message
. ..
Ah yes grasshopper - zee loops - zay are good.
The loop helps reduce noise since its dc-shorted and no static buildup,
and your socks won't stick to it. ;-)
but it takes more trees to hold it up



Oh thank you Master Rosser. I am a little wiser now. How long before I can
take the pebble from your hand or maybe just kick butt?

Loop Antennas
 

Michael wrote:

I had never hear of a loop antenna back in the 50s.

Loops started to come into their own with the invention
by C. C. Moore of the Cubical Quad circa 1939.
--
73, Cecil http://www.qsl.net/w5dxp