Hi Jimmie

IME the most critical part of quad tuning is F/B so you might like to
use that as a go/nogo test for your spreader experiments.

My thinking on metal spreaders would be about their length with respect
to wavelength. ie if they started approaching resonance of the operating
frequency (incl coupling to boom etc) I would expect pattern/gain & feed
Z to be affected. I wouldnt try real hard mind you, just plug the think
into a NEC engine.

Good news though..

Cheers Bob


Jimmie

I slid Al tubing over the supports for my two meter quad except for
the last two inches toward the tip and I cant tell any difference in
operation VSWR is the same. AGC voltage on my receiver is the same as
usual for a local repeater. Whether or not the boom ends of the tubing
were connected together also had no discernible effect.

Jimmie