Originally Posted by D. Peter Maus

On May 10, 1:15 am,
wrote: Hello,

I was at the beach yesterday and enjoyed spectacular shortwave
reception. When I got back home after that I tried to listen to
shortwave in my house but I didn't have a very good time of it.

I was wondering if there is a way to listen to shortwave in your
house. I have heard of something called an attic loop? Would that
work well? Are those easy to install and are they fairly inexpensive?

Thanks!

Andrew.



A loop can be expensive. There are also build-your-own solutions
that can be quite economical. It's all going to depend on your level
of technical skill, and your willingness to expand your skills and
technical understanding.

Your problems in at-home listening are based on the levels of
noise generated by items in the house, as well as signal loss
resulting from siding and other construction materials, ground and
other clutter. The composite result of attenuated signal at the
antenna, and higher noise levels from sources in the home make for
some pretty suckular listening.

The best solution is an external antenna. More signal and less
noise. A dramatic difference is possible.

Easiest would be a random wire through a 9:1 transformer to a
well shielded and grounded coaxial transmission line to your radio.
This can be all the improvement you need. Easily deployed. Easily
concealed, if that's an issue.

Loops are very good solutions. They can offer a level of noise
immunity. A properly selected diameter can provide less directional
reception at HF frequencies, making for simpler operation. That
said, smaller loops tend to be of lower gain, requiring
amplification to not only boost signal levels, but to overcome
losses in the transmission line for better noise figures. Such
loops, like the Wellbrooks, can run you a few hundred bucks just to
get one in the building. You build one for less, but that will
require some technical understanding of loops, transmission lines
and the field of antennae in general.

Loops in the attic....not the best solution. Mostly because
you're still in the building where noises are generated. Level of
noise in your receiver is proportional to the proximity of the
antenna to the source. Outdoors, away from the building is a
dramatically better way to go.

You may be surprised where at the sources of your troublesome
noise. Computers, routers, and printers, are horrid offenders, of
course. But the rectifier bridges in audio amps (Crowns are
notorious for this), HD tv sets (on or off), cable/U-verse boxes,
noises on the A/C line, and even some ground legs can all be noise
sources. Some, like rectifier bridges can be quieted with capacitors
across rectifier junctions to soak up the switching transient.
Others, more difficult. But there are always solutions to improve,
if not eliminate some noises.

ARRL publishes a terrific book on antennae, antenna theory, and
practical designs and construction tips.

And there are always sources, like this group, where the
technical knowledge is available to help you track down and maim, if
not kill, noise.

Dig in. Getting your hands working is a lot of fun.




p