DIY antenna for handheld transceiver

[Brad Lewandowski]

I'm going to try and make an antenna as shown in Kitplanes MAR 2006
("Rubber Duckie, Your'e the One..).
Does it matter if the copper foil is 1/4 or 1/2 inch wide?
Does the balun have to be right in the middle (if I want to put in
a PVC tube it wouldn't fit with a balun in the middle) or can it be at
the bottom of the dowel with longer leads?
Anybody make one of these successfully?

Thanks!

Brad

[RST Engineering]

"Brad Lewandowski" > wrote in message
oups.com...
>
> I'm going to try and make an antenna as shown in Kitplanes MAR 2006
> ("Rubber Duckie, Your'e the One..).

It works surprisingly well for such a simple little rascal.


> Does it matter if the copper foil is 1/4 or 1/2 inch wide?

The wider the foil, the wider the "goodness" of the bandwidth. Goodness is
purely a subjective term, and for a receiver you'd probably be OK with #12
or #14 copper wire stripped from a piece of romex if that's what you've got
on hand. I've built dozens of field-stripped antennas from house wiring
that was laying around and they all worked passaably well. The only reason
I used foil is that it lays flat against the dowel and is easy to work with
(besides the aforementioned bandwidth).



> Does the balun have to be right in the middle (if I want to put in
> a PVC tube it wouldn't fit with a balun in the middle) or can it be at
> the bottom of the dowel with longer leads?

The balun has to be in the middle if a dipole is what you are going after.
There is a design for an end-fed coil-loaded vertical dipole, but it
requires some special tiny coax (RG-174) and a fairly critical number of
turns around a fairly critical diameter dowel.

Having said that, you can solder the coax to the dipole copper elements on
the dowel, slide the dowel into a PVC Tee until the center of the dipole
lets you run the coax out the third arm of the Tee, and then attach the
balun as close to the antenna as you can. You can then glue as long an
arm(s) as you need onto the Tee to weatherproof the antenna.



> Anybody make one of these successfully?

Other than the one I did for the article? {;-)

Jim


>
> Thanks!
>
> Brad
>

[Brad Lewandowski]

One last question Jim,
I looked up the digi-key 240-2325-ND you reference in the article,
but the hole in the ferrite is only .043" high. The 174 coax appears to
be .103" OD. It doesn't seem like it would fit. Should I be looking for
a different balun? How about the 240-2337-ND with an .108" opening?
Thanks for your help.

Brad

On Nov 10, 1:16 pm, "RST Engineering" > wrote:
> "Brad Lewandowski" > wrote in ooglegroups.com...
>
>
>
> > I'm going to try and make an antenna as shown in Kitplanes MAR 2006
> > ("Rubber Duckie, Your'e the One..).It works surprisingly well for such a simple little rascal.
>
> > Does it matter if the copper foil is 1/4 or 1/2 inch wide?The wider the foil, the wider the "goodness" of the bandwidth. Goodness is
> purely a subjective term, and for a receiver you'd probably be OK with #12
> or #14 copper wire stripped from a piece of romex if that's what you've got
> on hand. I've built dozens of field-stripped antennas from house wiring
> that was laying around and they all worked passaably well. The only reason
> I used foil is that it lays flat against the dowel and is easy to work with
> (besides the aforementioned bandwidth).
>
> > Does the balun have to be right in the middle (if I want to put in
> > a PVC tube it wouldn't fit with a balun in the middle) or can it be at
> > the bottom of the dowel with longer leads?The balun has to be in the middle if a dipole is what you are going after.
> There is a design for an end-fed coil-loaded vertical dipole, but it
> requires some special tiny coax (RG-174) and a fairly critical number of
> turns around a fairly critical diameter dowel.
>
> Having said that, you can solder the coax to the dipole copper elements on
> the dowel, slide the dowel into a PVC Tee until the center of the dipole
> lets you run the coax out the third arm of the Tee, and then attach the
> balun as close to the antenna as you can. You can then glue as long an
> arm(s) as you need onto the Tee to weatherproof the antenna.
>
> > Anybody make one of these successfully?Other than the one I did for the article? {;-)
>
> Jim
>
>
>
>
>
> > Thanks!
>
> > Brad- Hide quoted text -- Show quoted text -