wrote in message ...
Gentlemen, I have an idea for a "portable AM radio" antenna to allow the
user to hear the station clearly while walking, no matter what direction
the radio is held.

Just have three bar antennas, aligned along the X, Y, and Z axes, like
http://en.wikipedia.org/wiki/Jacks , or independently placed inside the
case. A microchip would constantly pick the best signal from amongst
them. Maybe even just two axes would do.

Great for farmers who are walking around all day, and just can't give up
their favorite AM station for FM.

It has been done. It's a form of diversity reception. It would require a
radio with two separate receivers in it. I think the liklihood of a
manufacturer deciding to build a radio optimized for your two applications
is kinda slim.

Why not try two small radios and join their outputs? Mount them
corner-to-corner (90-degrees opposed) so that when one is
in the null, the other one is at the peak. Couple the hot sides
of each of the output jacks together through a pair of small resistors,
say 39 ohms. You probably need to know how to solder and
know where Radio Shack is for a few small parts.

Next time I'm at the swap meet, I'll see if I can find a matched set of
mini-cheapo portable radios and maybe try it myself.

"Sal"