aluminum tubing can be found at industrial pipe suppliers, or for short
pieces you can get tent poles to cut up. welding rod is another commonly
used material, copper pipe is another one for small antennas. some people
also use steel electrical conduit.

Insulating the elements will change the size they need to be... or you could
look at it that when you don't insulate the elements from the boom they
usually get shorter because they look fatter at the middle. there are
arguments for both methods, but if you use a metallic boom i wouldn't
insulate them because its more work if you don't have the proper tools and
insulators handy, if you use pvc or something else then they will be
insulated anyway.


"Doug McLaren" wrote in message
...
I'm looking to make a 2m/70cm yagi antenna for working satellites.
The plans are out there, and it seems quite simple. (Or I could pay
$73 to Arrow Antenna, but I'll give it a shot myself first.)

So I hit Home Depot, and the closest thing I found to the approprite
beams was 1/8th inch steel rods. (Basically piano wire.)

It ought to work, and is stiff enough to not bend much under gravity,
but it's heavy, and I'll be holding this thing ...

The local hobby shop has more piano wire that's smaller, but it's
still steel, and as you get smaller, it looses the needed rigidity and
it sags too much.

The instructions suggest hollow alluminum tubes, which should be light
and strong, and a good conductor to boot, but where can I find these?

Also, I've seen Yagi instructions that suggest a that the beams not be
insulated from the boom, and I've seen instructions that say they
should be insulated from the boom (or the boom should be an insulator,
like PVC pipe.) Does it make a big difference? Does it affect the
dimensions of the antenna?

Thanks in advance ...

--
Doug McLaren, , AD5RH
The face is familiar but i can't quite remember my name. Oh, there it is.