-=jd=- wrote:

On Tue 25 Oct 2005 09:31:33p, clu wrote in message
:


Since you mentioned coaxial cable ... can I use the cable TV coaxial
cable coming into my house for broadband/TV as an antenna to my
shortwave radio?


It may or may not offer any improvement. I doubt it would hurt anything to
try, if only to satisfy curiosity. If you do try it, be sure and advise your
results.

Thank you for the "best practices" knowledge about disconnectig an
external antenna from the radio when not in use.

You said it's a good argument for having a transformer (at least 1:1) in
your feed line ... is a "feed line" the wire that acts as an antenna?
What would the diagram look like to attach a direct path to ground?


Look here for some good info:
http://members.aol.com/DXerCapeCod/z_transformers.pdf
http://www.hard-core-dx.com/nordicdx...lab/index.html

Someone else mentioned an antenna wire around the perimeter of my house
would most likely blow up the portable radio (either Sony ICF-7600GR or
AOR 8200 MKIII B). Any truth to that?


It won't blow-up your radio, but it could overload the front-end and possibly
damage it. You can make a home-made attenuator around a 10kOhm pot to deal
with overload. Here's a link to the basic idea:

http://www.radiohc.org/Distributions/Dxers/zipten.html

I don't know what a lghtning arrester is, but I can easily look it up,
thanks.

You mentioned you wrap your own transformers. I think that's neat. I'm
not an electronics guy, but I am eager to learn. Do you just take a ton
of thin copper wire and wrap it around a spool a billion times?


The hardest part is finding the toroids. After that, it just takes a few feet
of wire. Well, plus an enclosure of some type (PVC is cheap), and either
binding posts and/or coax connectors. See the transformer links above...

Here is a link to a newer John Bryant transformer article:

http://www.dxing.info/equipment/impe...ing_bryant.pdf

And here is a link to a review of a transformer I used to make based on the
earlier Bryant article:

http://www.iserv.net/~n8kdv/xfmr.htm

dxAce
Michigan
USA