On Jun 10, 2:06*pm, Twitchell wrote:
In article ,
bpnjensen says...







On Jun 10, 12:55=A0pm, Twitchell wrote:
I've seen some car radio whip antennas that look like they have a wire wr=
apped
around them. =A0The wraps are not close but lazily spiral down the length=
of the
antenna.

Does this help reception? =A0Is the coil attached somehow to the car or j=
ust the
antenna itself?

twitch

My antenna on my minivan is like that.

I think the supporting whip is fiberglas/or some insulating material,
and the wire is the actual electrical element; and in the interest of
saving length and providing strength, they wrap the wire around the
slightly shorter antenna pole. *The wire is then connected to the lead
of the antenna. *It works fine, about as good as a metal whip of
similar length. *Antennas for cars are pretty uncomplicated
critters... :-)

I was wondering if I could improve my portable radio FM reception by wrapping it
like the car antenna by just wrapping it with a wire.- Hide quoted text -

- Show quoted text -

Where do you use your radio? If it's inside a building with a heavy
metallic or masonry contruction, that may be the problem.

To your question - my guess is not. FM wavelengths are fairly short -
about 1 meter in length - and your antenna is probably a pretty good
length already if it is a half-meter or so (roughly 20 inches or a bit
more). Wrapping a wire around it would not affect its resonant
wavelength, and attaching a wire to it may or may not help, but too
long an antenna is not terribly helpful as a rule either.

A better choice might be to either take the radio to a place where
there is interfering metallic or masonry building in the way, or make
an external antenna for it.