I'm sorry, this response contains some misleading advice.

Robert Macy wrote:

Just saw this thread and some very good suggestions.

One thought. Unless your close to the TV Transmitters, stay away from
using wire as the antenna. There is a good reason antennas are made
of tubes, not wire.

The reason usually is physical strength and rigidity. The larger
diameter also increases bandwidth, but often this isn't necessary to
proper operation.

At high frequency, like television transmission
frequencies, the current creates a repulsion field that pushes the
current away from the center of the conductor. In other words, all
the current travels on the outside surface of the wire. Look up the
term, "skin depth". At frequencies as low as 20MHz, more than 99% of
the current will be within 3 mils of the surface. The only easy way
to lower the losses in the antenna is to use large diameter
conductors, but since the inside of the conductor carries no current,
you don't need metal there, so it is ok to use hollow tubes.

This is true. However, in almost all cases the loss caused by using
wire, even very small wire is still negligible. Exceptions are antennas
which are very short in terms of wavelength, particularly at low
frequencies. As frequency increases, the length of an antenna of equal
performance decreases in direct proportion. However, the loss decreases
only as the square root of frequency. So antennas of the same wavelength
size become proportionally less lossy at higher frequencies.

Antenna manufacturers save themselves money by lowering material costs
and shipping weight. They use hollow tubes.

Another important reason for using hollow tubes is structural weight.

If you don't care about
weight or material cost, go ahead and use solid rods, 1/4 inch, or
even 3/8, but stay away from 18 Awg, way too small.

18 AWG wire won't result in appreciable loss for nearly any antenna.

One other thing, nature abhors sharp edges, that's why bubbles are
round, so don't use square tubes or sharp bar stock either.

Square stock is slightly lossier than round, but the loss will be
negligible when unsing any practical size.

Use
rounded tubes or rods. Even smoothing and polishing the surface
lowers the resistance.

Polishing won't make any detectable difference.

When you're done, passivate the surface of the
conductors to prevent corrosion over time. [meaning: paint the
antenna] Over time, corrosion will deteriorate your antenna's
performance.

It depends on the type of corrosion. But it would have to be severe
before becoming so bad as to cause an appreciable reduction in
performance. Aluminum, tin, and some other metals passivate themselves
by forming a hard insulating oxide layer on the outside. Unless you're
in a maritime climate, copper won't deteriorate in a way that matters,
either. Insulated wire is an easy way to prevent corrosion in an
unfavorable climate.

Rounded surfaces also means make your connections smooth
with nice transitions. As in, "if it looks good, it works good."

If only that were true! But unfortunately it isn't.

You
can use aluminum if the lengths are continuous and/or you make
connections using constant mechanical pressure, like a "lots of teeth"
star washer that has bitten down through the insulating oxide layer
held with a bolt.

This can cause more problems than it solves, if the bolt and washer are
the wrong metal such as steel. A good book on Yagi antenna construction
will tell you about techniques for working with aluminum.

All in all, it seems a lot easier to buy a fringe field antenna and
put that in your attic. But if you do it yourself, hope you're
successful, document what you built, and share it here.

With that I agree.

Roy Lewallen, W7EL