Antenna Questions...
 

Hello,

This isn't strictly a Ham radio question. So, I'll apologize up front.

A couple of years ago I picked up a CC AM Radio by Sangean. I love it.
Its a blast, especially at night, to try to pick up distant signals.
However, you can only play with it so much. It has an antenna screw on
the back. I've tried wiring in a piece of copper wire that looped
around my hous in an 'L' shape. That was fun, but it was also like
bringing in the world. I got alot of wierd signals (blurps and
screaches and 'dots') that I couldn't make heads or tails of. Also,
when the first thunderstorm came around I will admit to being a bit
freaked out by having a piece of copper wire hanging out the window. I
have heard from some Ham's that you can 'tune' an antenna, by length
(?), to get in certain stations, and that you can set something up to
trick a radio to think that a fixed length antenna is varying lengths.

So, to the web I went. And then I came here to usenet because frankly
there was *alot* of stuff, and I found alot of it very confusing.

So I am wondering if someone could lead me on the trail of some doc
that would help out. Do I need basic antenna theory? Is there something
easy to learn? Or can I find a diagram of something I can build and
jump right to that?

Any help would be appreciated, and again I apologize if this isn't
strictly a ham question. I am leaning that way, the fun I'm having with
this. Its just a bit daunting.

Thanks!

Jim

Did you check out the CC radio web site? Here are some turn-key solutions
that appear to be VERY easy to install and use. Good Luck.

Wayne-
(KC8UIO)

"Jimbo" wrote in message
oups.com...
Hello,

This isn't strictly a Ham radio question. So, I'll apologize up front.

A couple of years ago I picked up a CC AM Radio by Sangean. I love it.
Its a blast, especially at night, to try to pick up distant signals.
However, you can only play with it so much. It has an antenna screw on
the back. I've tried wiring in a piece of copper wire that looped
around my hous in an 'L' shape. That was fun, but it was also like
bringing in the world. I got alot of wierd signals (blurps and
screaches and 'dots') that I couldn't make heads or tails of. Also,
when the first thunderstorm came around I will admit to being a bit
freaked out by having a piece of copper wire hanging out the window. I
have heard from some Ham's that you can 'tune' an antenna, by length
(?), to get in certain stations, and that you can set something up to
trick a radio to think that a fixed length antenna is varying lengths.

So, to the web I went. And then I came here to usenet because frankly
there was *alot* of stuff, and I found alot of it very confusing.

So I am wondering if someone could lead me on the trail of some doc
that would help out. Do I need basic antenna theory? Is there something
easy to learn? Or can I find a diagram of something I can build and
jump right to that?

Any help would be appreciated, and again I apologize if this isn't
strictly a ham question. I am leaning that way, the fun I'm having with
this. Its just a bit daunting.

Thanks!

Jim

Hi Jim

Yes it can get quite daunting.

I guess you could immerse yourself in antenna theory but that may not
necessarily help. What you are trying to achieve is a) get enough signal
so that you can hear the stations and b) reduce the noise/interference
from undesired sources. Tuning is something you tend to do more for
transmitting because although a strong receive signal looks good on a
meter, what is more important is how much stronger than it is to the
noise. The idea of transmitting antenna tuning is to get maximum power
transfer from the radio to the antenna. Not an issue in your case. If
you are wandering across the shortwave and broadcast bands it is also
very fiddly having to tune where you go!

Antennas can also be cut to specific lengths to receive radiation from
particular directions. The problem here is that since you are listening
to various frequencies the length varies in inverse proportions to it.
What you cut the antenna for may have undesirable results elsewhere!

Not being much help am I? Here are some thoughts anyway.

- A high and clear a antenna is probably a good compromise. In my
experience horizontal antennas yield less noise than vertical ones.

- The radio should also have a ground connection that you should make to
a buried earth stake. Dont rely on mains earthing as that can induce
noise onto the signal.

- If the radio has side by side antenna terminals you may wish to use
open feeder (eg TV ribbon) to get away from the house electrical noises
before it joins to the antenna wire. The idea is that this ribbon wont
pickup any noise source it goes past. (eg fluoro's)

- If you are serious about receiving specific stations you can design
antennas for just that frequency.

- If it was my interest I'd probably put up a magloop with remote
tuning. From what I have read this seems to produce high signal to
noise ratio performance.

- Disconnect the antenna during storms. The electrical pulses can
damage/destroy your radio.

Now even more confused?

Cheers Bob VK2YQA

Jimbo wrote:
Any help would be appreciated, and again I apologize if this isn't
strictly a ham question. I am leaning that way, the fun I'm having with
this. Its just a bit daunting.

Thanks!

Jim