There are two things to keep in mind when you put a coil in a can.

1. The inductance will decrease due to the reduced voulme for the
magnetic energy. This is the same effect as using a brass slug to
change teh inductance of a coil for VHF applications.
2. The losses will increase due to the induced currents in the walls
of the container.

The further away the walls are the lower the effect. The various rules
of thumb you hear are just the result of someone determining what is
acceptable.

73 de K9GXC, Jim

On Fri, 02 Feb 2007 13:45:47 GMT, "Ceriel Nosforit"
wrote:

Quick, simple question:

Would a normal aluminum can be any good for RF shielding of a balun, or
would it for some reason not work? Should I connect it to ground?

And;
What does a transmatch do for me that a normal balun/transformer won't do
for me?

Thank you for your time.
Sincerecly,