Mike, just like you plan to do, I use a doublet on 80 and up, and tie the
feed line together at the base and feed it against ground as a Marconi T on
160M.
I use Deltrol 900-series open frame 30A relays to remotely do the switching
of the ladder line. These are officially rated to 2200VRMS but you can get
even more HV margin by prying the contacts further apart as N6RK describes
in May 2009 QST Hints and Kinks.
On 80 and up, the matching networks I use are link-coupled tuners, one per
band. And on 160M I use a L-network. So I end up with one Deltrol 900 SPDT
relay per band for the ladder line side of each tuner, and one relay per
band for the coax side of each tuner (I use HVAC-rated 30 Amp contactors
for that side).
Spec sheet for the Deltrol 900 series:
https://deltrol-controls.com/sites/default/files/pdf/data-sheet/900%20Series%20102011.pdf
You can see some of my relay and tuner arrangements here:
http://n3qe.org/tuners.html . You will also catch some glimpses of my crazy
radial network - specifically the radials the junction point for the
radials that run across the joists in the basement and out the other side
of the house :-)
Tim N3QE
On Wed, Apr 10, 2019 at 1:34 PM Mike DeChristopher <
mfdechristopher@gmail.com> wrote:
> Topbanders,
>
> During the winter, an icy pine branch saw fit to down my 160 inverted-L and
> so I've begun planning a replacement. As we're allegedly headed into the
> spring, and as it is unlikely I'll get to raise a tower with other work at
> the new QTH still going on, I'm planning on something easy for all band
> use.
>
> My plan is a 200' doublet (100' each side) about 100' high fed with ladder
> line. At the base will be a legal limit remote autotuner and thereafter
> hardline to the shack. That setup should handle 10-80. On 160, I'd like to
> short the ladder line together and feed as a T against the existing radial
> field.
>
> I know some of you are using similar setups, but are any of you doing it
> remotely as opposed to a "knife switch" in the shack? Any experience with a
> high power switching setup (relay type, circuit, mechanics, etc.)?
>
> 73,
> Mike N1TA
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