hello. I just had a few questions about building 2m antennas.

This will be used indoors. I havent decided if its worth the trouble to
climb around in the attic or if I should just mount it on the wall. I have
vinyl siding so hopefully that is a plus.

My first is about the classic ground plane built on a so239 connector. I
went with #14 wire and soldered the center wire on no problem. My question
is whats the sturdiest way to stick on the radials? I have a 100 watt iron
and still can't get a solid connection for the radials.

I was also considering just putting up a vertical dipole on the wall. I've
heard people say they had better luck with the ground plane but maybe they
didnt have the coax ran off to the side far enough or just dropped it
straight down? It seems a little tricky feeding it from the center and
having the antenna vertical but maybe a few wire tacks can fix that.

As a alternative to the dipole on the wall I also thought about just getting
a connector and soldering the wire directly to it bent upwards and then
using some flexible wire for the ground and let it hang below the shelf.
Would this work ok being connected directly to the radio?

What do you guys suggest?

thanks

Jim noname wrote:
My first is about the classic ground plane built on a so239 connector.
I went with #14 wire and soldered the center wire on no problem. My
question is whats the sturdiest way to stick on the radials? I have a
100 watt iron and still can't get a solid connection for the radials.

See the message in another thread, about using a hot-air gun to pre-heat
the connector before applying the iron. That'll do it.

#14 wire will tend to sag under its own weight, so it's better to use
thicker copper wire like #12. Some designs show the radials attached
with solder-tags, but in my experience they bend. It's better to crimp
radials through each of the four holes in the socket, and then solder
them on directly. Cut the radials to their final length *after* you have
completed the crimping and soldering.

There may be a problem with soldering to some kinds of plating, so
choose a connector made from brass as the base material. Drill the
surface plating out of the four holes, and also file it away around the
corners so you're soldering to bare brass. Also pre-tin the four corners
with solder before you crimp on the heavy wire radials. Then it will
solder easily.

If the SO239 doesn't have teflon insulation, screw on a PL259 to keep
the center pin from moving when the insulation softens, and leave it to
cool down before you remove the plug.

Finally, be aware that the feedline needs to run straight down through
the four sloping radials and some way beyond. If you notice any weird
behavior, it's probably due to RF currents on the surface of the
feedline - this type of antenna is quite prone to that problem. Two
large ferrite beads clipped onto the feedline will probably fix it; use
one right behind the PL259, and a second one about 19in down.


Having said all that, any 2m antenna will work much better outside! If
you're tied up in CC&Rs, take a look at the Ventenna concept for a
well-disguised outside antenna.



--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

http://members.home.nl/blues/scanner/jantenne.html

http://www.eham.net/articles/2418

lowcost, simple and good.
73 de heiner

Jim,
If your soldering iron isn't 'heavy' enough you can always
use a few bolts to attach the radials.
Another options besides the walls and desk top is the
ceiling,
hang the antenna from a hook. Or, if you're feeling
adventurous,
draw the antenna on a large sheet of paper with a graphite/lead
pencil, tape it where ever you want. Or use 'burglar alarm'
tape
on a window.
As Ian said, the 'best' option is to put the antenna
outside...
'Doc

"Jim noname" wrote in message
news:SIfvc.34985$eY2.14267@attbi_s02...
hello. I just had a few questions about building 2m antennas.

This will be used indoors. I havent decided if its worth the trouble to
climb around in the attic or if I should just mount it on the wall. I
have
vinyl siding so hopefully that is a plus.

I had a 1/4 wave 2m GP in the attic, built around an SO239 connector. Worked
like gangbusters. I later put up an Isopole outside, but in some directions
the attic antenna worked better.

My first is about the classic ground plane built on a so239 connector. I
went with #14 wire and soldered the center wire on no problem. My question
is whats the sturdiest way to stick on the radials? I have a 100 watt
iron
and still can't get a solid connection for the radials.

Don't try to solder the radials on to the connector. Get 4 spade lug or ring
terminals, and solder one to each wire. Fasten to SO239 with the mounting
screws. There is no wind in the attic; so you can use soft #16 wire if you
want. You can either put an insulator on the top of the vertical and hang it
from the peak of the roof, or nail a vertical piece of wood up from the
rafters. For the latter, fasten some sort of horizontal plate (wood,
plastic, metal) to the top, and mount the SO to that.

I was also considering just putting up a vertical dipole on the wall. I've
heard people say they had better luck with the ground plane but maybe they
didnt have the coax ran off to the side far enough or just dropped it
straight down? It seems a little tricky feeding it from the center and
having the antenna vertical but maybe a few wire tacks can fix that.

I would not tack the vertical dipole to a wall. Put insulators on the ends,
and run it between the rafters and the peak of the roof. You need to run the
coax at right angles to the dipole for as far as possible. Taping the dipole
to a thin piece of dry wood, or piece of plastic pipe might be OK.

As a alternative to the dipole on the wall I also thought about just
getting
a connector and soldering the wire directly to it bent upwards and then
using some flexible wire for the ground and let it hang below the shelf.
Would this work ok being connected directly to the radio?

What do you guys suggest?

thanks

I was able to bring up repeaters 60 miles away with 10W using the attic GP.

Tam/WB2TT

Don't try to solder the radials on to the connector. Get 4 spade lug or ring
terminals, and solder one to each wire. Fasten to SO239 with the mounting
screws.

Bingo, I was going to say the same thing.

It doesn't matter if your radials are droopy or not.

That's an excellent antenna for the attic.

jw
K9RZZ

Now you are on the air, here are a few more to look at !

http://www.cebik.com/hs.html
http://www.cebik.com/mvhf.html
http://www.cebik.com/moxbld.html

all are direct fed with 50 ohm coax and low cost.

walt

Jim wrote:

hello. I just had a few questions about building 2m antennas.

This will be used indoors. I havent decided if its worth the trouble to
climb around in the attic or if I should just mount it on the wall. I have
vinyl siding so hopefully that is a plus.

My first is about the classic ground plane built on a so239 connector. I
went with #14 wire and soldered the center wire on no problem. My question
is whats the sturdiest way to stick on the radials? I have a 100 watt iron
and still can't get a solid connection for the radials.

I was also considering just putting up a vertical dipole on the wall. I've
heard people say they had better luck with the ground plane but maybe they
didnt have the coax ran off to the side far enough or just dropped it
straight down? It seems a little tricky feeding it from the center and
having the antenna vertical but maybe a few wire tacks can fix that.

As a alternative to the dipole on the wall I also thought about just getting
a connector and soldering the wire directly to it bent upwards and then
using some flexible wire for the ground and let it hang below the shelf.
Would this work ok being connected directly to the radio?

What do you guys suggest?

thanks

I've made several of these that work well from an SO-239, and coat hangers.
Talk about cheap, but they work well anyway. The coat hanger radials are
stiff enough to support themselves, and after sandpapering off the paint
down to bare metal, they solder OK directly to the SO-239. The radials
should be slightly longer than the vertical section and slope down at
roughly a 45 degree angle. Of course, if the antenna is outside, it will
rust. But if it's indoors, no problem. Also, I soldered a spade lug to the
top of the vertical section allowing me to hang it from the center beam of
the roof on the inside of my attic.

"Jim noname" wrote in message
news:SIfvc.34985$eY2.14267@attbi_s02...
hello. I just had a few questions about building 2m antennas.

This will be used indoors. I havent decided if its worth the trouble to
climb around in the attic or if I should just mount it on the wall. I
have
vinyl siding so hopefully that is a plus.

My first is about the classic ground plane built on a so239 connector. I
went with #14 wire and soldered the center wire on no problem. My question
is whats the sturdiest way to stick on the radials? I have a 100 watt
iron
and still can't get a solid connection for the radials.

I was also considering just putting up a vertical dipole on the wall. I've
heard people say they had better luck with the ground plane but maybe they
didnt have the coax ran off to the side far enough or just dropped it
straight down? It seems a little tricky feeding it from the center and
having the antenna vertical but maybe a few wire tacks can fix that.

As a alternative to the dipole on the wall I also thought about just
getting
a connector and soldering the wire directly to it bent upwards and then
using some flexible wire for the ground and let it hang below the shelf.
Would this work ok being connected directly to the radio?

What do you guys suggest?

thanks

"J999w" wrote in message
...
Don't try to solder the radials on to the connector. Get 4 spade lug or
ring
terminals, and solder one to each wire. Fasten to SO239 with the mounting
screws.

Bingo, I was going to say the same thing.

It doesn't matter if your radials are droopy or not.

In fact, you want them to droop! About 45 degrees droop will give 50 Ohms
impedance, which you can't get with a dipole.

Tam

That's an excellent antenna for the attic.

jw
K9RZZ

"Jim noname" wrote in message
news:SIfvc.34985$eY2.14267@attbi_s02...
hello. I just had a few questions about building 2m antennas.

This will be used indoors. I havent decided if its worth the trouble to
climb around in the attic or if I should just mount it on the wall. I
have
vinyl siding so hopefully that is a plus.

My first is about the classic ground plane built on a so239 connector. I
went with #14 wire and soldered the center wire on no problem. My question
is whats the sturdiest way to stick on the radials? I have a 100 watt
iron
and still can't get a solid connection for the radials.

I was also considering just putting up a vertical dipole on the wall. I've
heard people say they had better luck with the ground plane but maybe they
didnt have the coax ran off to the side far enough or just dropped it
straight down? It seems a little tricky feeding it from the center and
having the antenna vertical but maybe a few wire tacks can fix that.

the 'classic' method of doing a vert dipole is to use a copper pipe for the
lower segment, and running the coax up to the antenna through the pipe. I
built a 6 meter vert dipole that way.

My suggestion however is a j-pole , either in the attic, or you can
literally hang it from a wall.

I built one guy one on by hot gluing an 16 gauge bare wire to the back of a
plastic poster holder in the correct dimensions, all you see is the RG-58
coming down out of it. The hardest part was getting the cable supported
properly.

Mine (made from 12 gauge solid copper) is tied onto a support beam in the
attic with nylon wire ties, and the feed line runs off horizontally, the
choke coil supported on the next beam.