Grant KZ1W and John KK9A,
Thanks for your thoughts. I see your point about wire versus the aluminum
tubing, I am a work in progress with EZNEC but will try to model it. The
coils are the Force 12 first generation Delta coils that were used on a Delta
140, 40M rotatable dipole. I will measure the inductance and see if I can
model the antenna. I don't know how to include the
tower in the modeling but i will see if i can figure it out. I saw in ON4UN's
book Low Band DXing an option of sloping the vertical dipole away from the
tower. This might reduce the interaction. It will be fun playing with the
idea. Something to do while staying at home during this pandemic hihi
Bob
K6UJ
> On Jul 27, 2020, at 8:20 AM, Grant Saviers <grants2@pacbell.net> wrote:
>
> As others said, the EF180x design is swaged tubes with steep tapers and thus
> pretty useless as a template for a wire antenna. (and hard to model) I would
> measure the coil inductance, probably all that matters since F12 likely has
> the SRF in an ok place. Then plug L into EZNEC and find a placement that
> resonates with your total wire length. Might be a good project for AutoEZ,
> especially if you include the tower model.
>
> Grant KZ1W
> Tornado tuned EF180C w/o LL @ 100ft
>
> On 7/26/2020 21:22, Robert Harmon wrote:
>> Anyone have a manual for one of the Force 12 80M rotatable dipoles? Like
>> the EF-180S or similar ? I want the one with loading coils not the linear
>> loaded version.
>> I am thinking about duplicating one using antenna wire and I think I have
>> the Force 12 loading coils already. I am thinking about hanging it from
>> the side of my tower
>> to see how it performs as a vertical dipole.
>> thanks,
>> Bob
>> K6UJ
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