[TowerTalk] 2 element 40m steppir yagi

[Jeff Stai WK6I]

At 09:51 AM 10/7/2004, you wrote:
>Have I totally misjudged Towertalkians interest? 

perhaps - but be that as it may - you may want to take it up on the steppir list:

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/SteppIR/

I am certain you will generate more discussion there!-)

I had a discussion with a passing stranger by the steppir table last april 
in Visalia - we had this idea of adding an aluminum sleeve over the ends of 
the elements - the steppir elements would then capacitively couple with the 
sleeves as they passed inside to create a sort of linear loading - I have no 
idea if this is mechanically or electrically practical. Try or model it and 
see.

There's another concept regarding simply running wires along or above the 
elements for the lower band, and letting the wires droop off the end - a 
sort of piggyback antenna. This would mess up the tuning for the higher 
bands to some degree, but perhaps a workable design with new settings could 
be found. I expect that changing the element lengths would also have the 
effect of tuning the low band antenna. I think there was a design in an old 
QST that had vertical supports on the boom so that the droopy wires would 
angle down to the element ends to reduce the interaction - though perhaps
some amount of interaction would allow for tuning the low band antenna.

You could at least do the same droopy antenna in the boom direction for a 
rotatable dipole without messing up the tuning.

I agree that a 2-element 40-6 would have installation and (perhaps) 
portability advantages!

- jeff wk6i


--
Jeff Stai               jds at twistedoak.com
Twisted Oak Winery      http://www.twistedoak.com/
Rocketry Org. of CA     http://www.rocstock.org/
Amateur Radio           WK6I