Topband: Extreme directivity

[Keith Jillings (G3OIT)]

Ford Peterson wrote:


> Forgetting about the legality of the experiment for the moment, modulate
> that 432 carrier at 1.832MHz.  This gadget is going to throw a WHOPPING spur
> on Topband.  You are going to hear that spur without-a-doubt.
> 
> The question is: will the modulation radiate well?  Will the beam form or
> not?  Will the wave front propagate so as to conform to the 70cm antenna's
> beam pattern?  Or will it propagate like you were loading a coat-hanger on
> Topband?

I noodled about the same idea a while ago.

Why not go the whole way, and modulate a laser beam with the 1.8MHz 
signal?    How much of the laser beam would radiate my 160m signal?
And over what distance?   Would I have to squirt the laser at you before 
you'd hear me?

Imagine that laser (it would need to be a pretty powerful one) 
squirting, say, at the moon: ah, no, the ionosphere would stop the 160m 
moonbounce from getting back to earth, wouldn't it?

I've just not actually got round to building the modulator to do that 
with the laser.   Give me time...

I like out-of-the-box thinking ;)

Best 73,


Keith
G3OIT