Topband: Shunt feeding AB-577/621

[Joe Subich, W4TV]

On 2018-10-01 11:47 AM, N4ZR wrote:
 > I have an AB-577 with a C-3E on top, and am interested in the
 > possibility of shunt-feeding it for 160 - 100 watts only.  Anyone have
 > any experience with doing this?  Are the section-to-section joints
 > adequately conductive?

The section joints should be adequately conductive given the surface
area.  The big questions would be an adequate connection at the top
and conductivity through the "launcher."

> My other option is an inverted L. Should I maybe just go ahead with
> that?
Since the standard AB-577 is 48' tall, even with the boom of your
C-3E you are only about 1/8 wave tall on 160.  It will take a good
deal of additional top loading to make the standard AB-577 reasonable
on 160 meters ... I'd consider hanging an inverted L off the side.
Probably easier in the long run.

73,

    ... Joe, W4TV


On 2018-10-01 11:47 AM, N4ZR wrote:
> I have an AB-577 with a C-3E on top, and am interested in the 
> possibility of shunt-feeding it for 160 - 100 watts only.  Anyone have 
> any experience with doing this?  Are the section-to-section joints 
> adequately conductive?  I would plan to use an omega match, because I'm 
> guessing it would be well short of a quarter wave.
> 
> My other option is an inverted L.  Should I maybe just go ahead with that?
>