"Buck" wrote in message
...
On Fri, 8 Jun 2007 03:26:18 -0400, "Al Dalton"
wrote:

I an not a licensed radio amateur, but I couldn't think of a better group
to
ask about antennas. I like listening to shortwave broadcasts. I'd like to
build a good antenna system that will work well. The long wire antennas
are
pretty much out of the question, although I have considered trying it.
Space
is somewhat limited. The broomstick antenna looks like it might be my best
choice. What do you think? Can you make any suggestions. Thank you.


Al


There are several things to consider. I don't know how much you know
about antennas, but I see you have done some research, so that's a
good sign. Hopefully you will understand what I am about to say.

My father, also an avid SWL, used to use a long wire antenna. Then
one day he bought an antenna tuner kit for $10 about 15 years ago. It
really wasn't much, just a couple of small capacitors and a piece of
laminated wire he had to wrap around a pill bottle. He added his own
bypass switch and was excited to show me the difference the tuner made
to his signals.

I wasn't as surprised at the results as I was his initiative to buy
and build the tuner kit.

Anyway, he moved and we ran a wire around his attic about four trips.
The wires were spaced about 3 inches apart and just looped the attic
from corner to corner. I don't know how long it was, but it turned
out to be much better than the long wire. He hooked up his tuner and
radio and used it until he moved out. It was extremely sensitive.

My suggestion, for SWL, is to run as much wire over as large an area
as possible. If you are limited to indoors, I suggest the attic idea
if possible.

If you don't have the room, look for the largest area possible to
spread wire. If you find the best you can do is the broomstick idea,
(I assume it is a dowel wrapped with wire) then you may have to use
that. The larger the diameter, the better.

Research the antenna tuners. You don't have to worry about power
levels, so any small capacitor will do. Make one, or buy a kit and
add it to your antenna. You won't regret it.

Dad's tuner consisted of a pair of tuning capacitors out of two small
AM radio receivers with a piece of enameled wire wrapped around a
large pill bottle. The wire was tapped twice the distance of the
previous tap, for example, if the first tap was at the 4th wrap, 8
turns later, the third was 16 turns from the previous, etc.

There are several home-brew plans on the internet. I highly recommend
it if you are wanting to pull out the weak signals.

Good luck, I hope you find what you need and enjoy your listening.

When I was a kid I was into AM swling, finding obsure AM BCB radio stations.
It was really great because if you sent these stations a letter saying you
heard them and enough about what you heard, when you heard it they would
send you the equivalent of a QSL card. Radio was a Halicrafter S40-B with a
wire aound the eve of the house for an antenna. One of the books in the
school library had plans for a tuner and a one tube pre-amp. Boy did this
make a difference . I built the tuner first but I think it helped the most.
The preamps help was most noticable up on the shortwave and ham bands,
especially arounf 15,10 and 11 meters.

Jimmie

"Al Dalton" wrote in message
...
There are several things to consider. I don't know how much you know
about antennas, but I see you have done some research, so that's a
good sign. Hopefully you will understand what I am about to say.

My father, also an avid SWL, used to use a long wire antenna. Then
one day he bought an antenna tuner kit for $10 about 15 years ago. It
really wasn't much, just a couple of small capacitors and a piece of
laminated wire he had to wrap around a pill bottle. He added his own
bypass switch and was excited to show me the difference the tuner made
to his signals.

I wasn't as surprised at the results as I was his initiative to buy
and build the tuner kit.

Anyway, he moved and we ran a wire around his attic about four trips.
The wires were spaced about 3 inches apart and just looped the attic
from corner to corner. I don't know how long it was, but it turned
out to be much better than the long wire. He hooked up his tuner and
radio and used it until he moved out. It was extremely sensitive.

My suggestion, for SWL, is to run as much wire over as large an area
as possible. If you are limited to indoors, I suggest the attic idea
if possible.

If you don't have the room, look for the largest area possible to
spread wire. If you find the best you can do is the broomstick idea,
(I assume it is a dowel wrapped with wire) then you may have to use
that. The larger the diameter, the better.

Research the antenna tuners. You don't have to worry about power
levels, so any small capacitor will do. Make one, or buy a kit and
add it to your antenna. You won't regret it.

Dad's tuner consisted of a pair of tuning capacitors out of two small
AM radio receivers with a piece of enameled wire wrapped around a
large pill bottle. The wire was tapped twice the distance of the
previous tap, for example, if the first tap was at the 4th wrap, 8
turns later, the third was 16 turns from the previous, etc.

There are several home-brew plans on the internet. I highly recommend
it if you are wanting to pull out the weak signals.

Good luck, I hope you find what you need and enjoy your listening.

buck
N4PGW

I do know a fair amount about antennas and tuners. I'd have the no code
tech license if I could remember the stuff you really don't need to know
(for the test). My memory just isn't good enough, and memorizing some of
that stuff isn't even relevant to whether or not we know what we're doing.

As I understand it, an antenna tuner is the single most important thing
involved? That makes sense. A tuner adjusts the overall resistance of the
circuit (impedance). Right? I have looked up everything I could find and
found a tuner for 60 bucks. I can't spend that on a tuner right now. I
should probably make one.

Are there any plans (w/parts list) on the Internet? Where might I find
them? Thank you.

Al


Just abot any decent book on ham radio has plans. My older tuner was very
similar to the big KW tuners but the coild used a sling tap instead of a
roller inductor and he caps were small receiver typed instead of vaccum
variables. This made it very cheap.