Horizontal Loop for 2m SSB
Tom Rutherford
Brand new to the newsgroup, here, and even though I did the old "Find"
routine, I couldn't find what I need.
Does anyone know where I can get instructions (preferably cookbook, but if
they come with formulas, I can deal with that, too) for building a 2m SSB
horizontal loop? I live in an apartment, which is pretty much a Faraday
cage, but I get out pretty well from my balcony, at least to the east(ish)
of the building. I have a discone out there right now, clamped to the floor
stand of an old oscillating fan that it used to be attached to. :-) I have
a similar portion of a floor lamp that I want to mount the loop onto. I
need something that will cover at least the 180º that my discone can radiate
in, as well as it does. Since 2m SSB is typically horizontal, the discone
doesn't do too well. Any help will be greatly appreciated.
--
-- 73 DE Tom Rutherford, N8EUJ, Burton, MI
"She said it was either her or the ham radio. Over."
nm...@wt.net
Myself I'd probably stick a small 3 el yagi on that
lamp mast if you had room..
Good bit more punch for SSB, and being things are
reciprocal, it will improve reception. If you squeeze
an extra 6 db from the antenna system, that's like
taking 50 watts and turning it to 200.
Best deal on an "amp" you will find.. :)
I'm not sure the gain using a halo, but I suspect
it's probably pretty close to a dipole. Maybe a tad
more, but it's not going to be a drastic difference.
A loop has some gain broadside vs a dipole, but I'm
not sure what you get running one on it's side.
John KD5YI
Not very good. Most of the RF goes up. It is particularly bad along the
axis of the driven wire (assumes wire driven in the center). Not quite
as bad normal to that axis. Might be improvable by feeding the corner.
I think a simple vertical would do better.
Cheers,
John
John KD5YI
I forgot that the OP wanted horizontal polarization. Well, if it were
me, I'd make the loop vertical and feed the bottom center. That will
produce a horizontally polarized signal much better than the horizontal
loop and with about the same directivity.
John
Jeff
A 'Halo' is the usual answer, or if more space is available crossed dipoles.
Jeff
Edward Feustel
<t...@nospam.invalid> wrote:
>Hi, All.
>
>Brand new to the newsgroup, here, and even though I did the old "Find"
>routine, I couldn't find what I need.
>
>Does anyone know where I can get instructions (preferably cookbook, but if
>they come with formulas, I can deal with that, too) for building a 2m SSB
>horizontal loop? I live in an apartment, which is pretty much a Faraday
>cage, but I get out pretty well from my balcony, at least to the east(ish)
>of the building. I have a discone out there right now, clamped to the floor
>stand of an old oscillating fan that it used to be attached to. :-) I have
>a similar portion of a floor lamp that I want to mount the loop onto. I
>need something that will cover at least the 180º that my discone can radiate
>in, as well as it does. Since 2m SSB is typically horizontal, the discone
>doesn't do too well. Any help will be greatly appreciated.
There is an antenna that Cushcraft used to make called a big wheel.
It had three full wave loops attached in parallel at the center.
I have 4 stacked big wheels which suppress vertical emission and
emphasize horizontal transmission. I have used this on 2M sideband
and FM. If you can get the instructions for a single big wheel from an
old ARRL antenna book, then I can give you some hints on phasing.
I expect that you will only be able to stack 2 on your balcony.
73,
Ed, N5EI
Tom Rutherford
<nm...@wt.net> wrote in message
news:3a19ea84-0424-4d5c...@glegroupsg2000goo.googlegroups.com...
Thanks much. I'll have a look at that link and see what's what. The Yagi
would be nice, but running out on the balcony and moving it around all the
time isn't practical. That's why I wanted something fairly omnidirectional,
as much of "omni" as I can get, anyway. Since I remember what my
communications instructor told us about loops (they radiate equally poorly
in all directions <g>), I figured this would be the most practical solution
for what I want to do.
Tom Rutherford
"Edward Feustel" <efeu...@hughes.net> wrote in message
news:ugucs69166q4cdlhh...@4ax.com...
Thanks, Ed. I'll give it a look-see.
nm...@wt.net
> The Yagi
> would be nice, but running out on the balcony and moving it around all the
> time isn't practical. That's why I wanted something fairly omnidirectional,
> as much of "omni" as I can get, anyway. Since I remember what my
> communications instructor told us about loops (they radiate equally poorly
> in all directions <g>), I figured this would be the most practical solution
> for what I want to do.
Another possible idea could be the turnstile.
That is horizontal, pretty omni, and pretty simple
to build. Just a set of crossed dipoles fed 90 degrees
out of phase. I think you would have less gain vs
the broadside of a dipole, but you wouldn't have the
nulls off the ends.
tom
>
> Not very good. Most of the RF goes up. It is particularly bad along the
> axis of the driven wire (assumes wire driven in the center). Not quite
> as bad normal to that axis. Might be improvable by feeding the corner.
>
> I think a simple vertical would do better.
>
> Cheers,
> John
>
Not for SSB it wouldn't. 20dB or so isolation V to H. Useless unless
within less than normal FM range.
On the flip side I've done well over 100 miles car to car with single
halos on each end with roughly 80 watts. And up to 200 with 2 stacked
halos (3 foot stacking, not much really) to a single 3 wavelength yagi
on the other end. Not a one time thing, I used to drive NNY at about
1000 miles per week doing service during the early 80's.
There are better things than the halo. The omni-angles are quite a bit
better, especially on the pattern and are simple and rugged. Less than
1 dB gain change over 360 degrees toward the horizon. A Motorola design
(that I don't remember them using) that got re-purposed for amateur.
And then there's the Big Wheel and a modern twist on it that is even
better and smaller.
tom
K0TAR
Irv Finkleman
with
a balcony on the side, then you would do with a simple dipole as any
signal sent into the building is only wasted. I am not sure but it would
probably have a good off balcony signal pattern too -- better than most
other antenna arrangements I can think of/
It's cheap and quick and wouldn't take much effort to try.
Irv VE6BP
"Tom Rutherford" <t...@nospam.invalid> wrote in message
news:iq729m$afq$2...@dont-email.me...
Jim Lux
A horizontal dipole in front of a screen or single reflector would have
a "pattern" that is 100+ degrees wide.
Stack a couple vertically, say a meter apart, and you squeeze the
vertical beam width significantly, which is probably what you want.
What you *might* want to do is look for a low gain TV antenna for the
upper VHF bands (e.g. Channel 7-13): one of those two bay things with a
bowtie in front of a screen.
Tom Rutherford
"Irv Finkleman" <fin...@shaw.ca> wrote in message
news:X5Ixp.64887$0s5....@newsfe17.iad...
> Consider the fact that as it is on a balcony, I assume there is a building
> with
> a balcony on the side, then you would do with a simple dipole as any
> signal sent into the building is only wasted. I am not sure but it would
> probably have a good off balcony signal pattern too -- better than most
> other antenna arrangements I can think of/
>
> It's cheap and quick and wouldn't take much effort to try.
>
> Irv VE6BP
I might just go that direction, Irv, depending on how things look with other
designs. Thanks!
Ian Jackson
<t...@nospam.invalid> writes
>
>"Irv Finkleman" <fin...@shaw.ca> wrote in message
>news:X5Ixp.64887$0s5....@newsfe17.iad...
>> Consider the fact that as it is on a balcony, I assume there is a building
>> with
>> a balcony on the side, then you would do with a simple dipole as any
>> signal sent into the building is only wasted. I am not sure but it would
>> probably have a good off balcony signal pattern too -- better than most
>> other antenna arrangements I can think of/
>>
>> It's cheap and quick and wouldn't take much effort to try.
>>
>> Irv VE6BP
>
coverage if half the RF will be coming back into the building, and
getting lost.
However, in the interests of minimising interference (to and from the
electrical devices in the building), it might be advantageous to
minimise radiation/reception in that direction by using something at
least 'somewhat' directional - maybe a 2-element yagi, or an HB9CV?
http://www.mydarc.de/dk7zb/HB9CV/Details-HB9CV.htm
<http://webcache.googleusercontent.com/search?q=cache:c2TRLwa5UtoJ:www.wr
aith.sf.ca.us/electronics/radio/+hb9cv+antenna+144&cd=8&hl=en&ct=clnk&sou
rce=www.google.com>
and hundreds more.
>I might just go that direction, Irv, depending on how things look with other
>designs. Thanks!
>
--
Ian
Tom Rutherford
> with
> a balcony on the side, then you would do with a simple dipole as any
> signal sent into the building is only wasted. I am not sure but it would
> probably have a good off balcony signal pattern too -- better than most
> other antenna arrangements I can think of/
>
> It's cheap and quick and wouldn't take much effort to try.
>
> Irv VE6BP
I might just go that direction, Irv, depending on how things look with other
designs. Thanks!
--
Tom Rutherford
<nm...@wt.net> wrote in message
news:9d937043-6175-4e25...@glegroupsg2000goo.googlegroups.com...
That's another good idea. Thanks. Are the elements of a turnstile spaced a
quarter wavelength apart, or are they pretty much on top of each other?
Jim Lux
On top of each other. Fed 90 degrees apart.
But I'd try a dipole first.
Tom Rutherford
"Jim Lux" <james...@jpl.nasa.gov> wrote in message
news:iq95pv$jsk$1...@news.jpl.nasa.gov...
How far behind the driven element should the reflector be? A quarter
wavelength?
> Stack a couple vertically, say a meter apart, and you squeeze the vertical
> beam width significantly, which is probably what you want.
Hmmm...! :-) That might be interesting, too. Feed them 90º out of phase?
> What you *might* want to do is look for a low gain TV antenna for the
> upper VHF bands (e.g. Channel 7-13): one of those two bay things with a
> bowtie in front of a screen.
Think I'd need some kind of a balun to get the impedences to match?
Tom Rutherford
Gotcha. Yeah, a dipole would be simple enough.
Jim Lux
You got it.
>
>> Stack a couple vertically, say a meter apart, and you squeeze the vertical
>> beam width significantly, which is probably what you want.
>
> Hmmm...! :-) That might be interesting, too. Feed them 90º out of phase?
Feed them in phase.
>
>> What you *might* want to do is look for a low gain TV antenna for the
>> upper VHF bands (e.g. Channel 7-13): one of those two bay things with a
>> bowtie in front of a screen.
>
> Think I'd need some kind of a balun to get the impedences to match?
Maybe.. depends on the antenna.
But consider that they might actually have a 75 ohm impedance, which
will be close to what you need.
JIMMIE
I would go with a 2M QUAD, Very easy to build cookbook style. on site
from scrounged materials. Ive used one from an apartment shooting
through a balcony door. PVC mast was made from a couple of scrap
pieces I got from the handy man. Pipe was selected so that one would
slide inside the other. Apply padding to ends to protect ceiling and
floor Think I wedged a piece of cardboard to lock the slip joint.
Inovate as required. The quad can be asily put together with out
benifit of test equipment and expected to function reasonably well
without additinal tweaking. However a knockdown Yagi can be buit ahed
of time and the elements stored inside the boom. Both are very handy.
Jimmie
Tom Rutherford
Peachy. Nice, short boom.
>>> Stack a couple vertically, say a meter apart, and you squeeze the
>>> vertical
>>> beam width significantly, which is probably what you want.
>>
>> Hmmm...! :-) That might be interesting, too. Feed them 90º out of
>> phase?
>
> Feed them in phase.
Ah! Okay.
>>> What you *might* want to do is look for a low gain TV antenna for the
>>> upper VHF bands (e.g. Channel 7-13): one of those two bay things with a
>>> bowtie in front of a screen.
>>
>> Think I'd need some kind of a balun to get the impedences to match?
>
> Maybe.. depends on the antenna.
>
> But consider that they might actually have a 75 ohm impedance, which will
> be close to what you need.
I should probably invest in an antenna matcher. Think I've got one for 11m,
but that wouldn't do me much good. :-)
Tom Rutherford
"JIMMIE" <JIMMIE...@YAHOO.COM> wrote in message
news:c1d7d229-3816-4c89...@q20g2000vbx.googlegroups.com...
Jimmie
Thanks, Jimmie. I was wondering about the quad, what kind of a pattern it
put out, etc. Gotta hit Google for some research.
Alexandre Fernandes
John Doe
wrote: