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Old August 4th 03, 07:08 AM
Robert Jeffares
Posts: n/a

Dear David,

For good radio reception there is no substitute for a decent wire antenna,
and a lead in from the antenna to your radio [we'll get to how you connect
it to the radio] AND a GOOD EARTH CONNECTION.

The best receive antenna is as high as possible, and as long as possible
with the wire running in the general direction of the station(s) you want to
hear. [this is not always possible]

Amateur Operators use tuned antennas to resonate on the frequency band they
are using, and it's true a resonant antenna works well as a receive antenna.

But on the AM Broadcast band a resonant antenna is difficult to construct.
So whatever you do is going to be a compromise.

A DX er constructs a loop antenna with a number of turns of wire on a frame
which may be 1 m square and uses it to null out interfering stations and
pull in the desired station using a high gain communications receiver.

An AM radio listener can do well with a long wire if you can get it up off
the ground and 10 m or 20 m is better then nothing.

If you want to get pedantic you need some sort of matching device between
the aerial and the coax you will use to run the signal into the house and
onto your radio. Measuring the feed point impedance of a random length of
wire involves a lot of theory a lot of messing around, and won't make any
difference you will notice so a good soldered connection between the centre
wire [thats center to you] and the aerial wire is all you need.

At the other end you need to have a good earth connection.


The kind of connection that electricians make is OK for appliance safety
[well it's supposed to be] but it's likely to carry a lot of AM Band
interference induced from every kind of source connected to the mains.

A copper pipe about 1 m long buried in the ground with a well connected
copper wire soldered to it which runs into your radio and connects to the
"earth" connection will pull the noise and hash down considerably.

If your radio does not have an "Earth" connection and you can't get into it
to hook onto the frame [the headphone socket frame is radio earth] you can
wind a coil with insulated copper wire on a suitable former. I used to use
the centre from a toilet roll, wind on 30 - 50 turns depending what wire I
could get, and connect this between the aerial wire and the earth wire, then
drape the coil across the top/back of the radio where the ferrite antenna
is. The arrangement is a simple transformer, which delivers the signal from
the aerial into the radio.

If you live on a farm you can run wire quite a long way, but most people
live in city spaces that run to 1/2 acre at best just don't have a lot of
space to put up wire antennas.

Vertical antennas are difficult because wherever you live there will be
rules limiting the height of anything you put up and the higher you go the
more engineering stuff you have to be involved with.

Mothers are a limiting factor. Either your mother or the Mother of your
children will object to large unstable looking structures. [long before the
local body engineer]. Neighbours get fussy too, whatever you do make sure
you don't upset anyone. Ask first. Watch out for power lines, phone lines,
Cables of any sort.

If you are interested in Amateur Radio track down the local amateur radio
club. The club will have members who will share information ideas, and show
you their inventions. They may have classes you can attend.

The local library will have books with diagrams which will help you, and you
can spend hours on the internet searching aerial, antenna, dipole, long
wire, and beverage antenna. You won't have the space for a real long wire or
a beverage antenna [ unless you are Very Lucky] but you need to look at the
theory of how they work.

Good Luck..



"David Berchtold" wrote in message
Dear Friends,

I have posted to this group on a number of occasions and have received
a weath of information. For that I am appreciative. This time I am
seek help with AM (and possibly FM) radio reception.

My question is:

What are the best ways to improve radio reception?

Here is an idea of what brought this question to light. I live in
Erie, Pennsylvania, a port city on Lake Erie. Right across the lake
is Canada (a distance of about 20 to 25 miles). Quite frequently,
like everyday, I enjoy the offerings of Canadian radio. CKOC AM 1150,
Hamilton, CHUM AM 1050, Toronto, and CFCO AM 630, Chatham-Kent are
among my favorite radio stations. I would like to know how to improve
the reception of these stations with the resources that I possess.

I have an Electro Brand Multiband radio that I inherited from my
father. This is a great radio for reception, but I use this for
mostly outdoor DXing. I am not sure how to attach an external antenna
to it.

I have several general purpose radios throughout the house. The ones
that I find I have the best luck with are from Radio Shack. (where
else?) I have also purchased a Ring Antenna from Radio Shack. I had
the idea of somehow attaching the Ring Antenna to above mentioned
Electro Brand radio. The instructions, however, were not clear about
how to do this. Maybe I missed something.

I also have a crawl space/half attic that is presently being used to
store nothing but insulation and hold up a roof. I believe that there
is plenty of room up there. The possibility of a wire antenna layed
from front of house to back of house is an extremely good possiblity,
but again I am unsure of how to connect radio with antenna.

I am also considering a more costly investment by getting into ham
radio. I would like to construct an antenna in back yard. But once,
again, how does the antenna get connected to radio. Any help would be
greatly appreciated.

Thank You,

David B. Berchtold
Radio Listener and Fan from Erie, PA