Thread: Vincent antenna
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Old December 5th 07, 03:32 PM posted to rec.radio.amateur.antenna
art art is offline
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Default Loading Coils; was : Vincent antenna

On 5 Dec, 06:29, Cecil Moore wrote:
Roy Lewallen wrote:
Take a look at my 2005 measurements and see if you can do what Cecil and
Yuri failed to do coherently -- use the "replacement" concept and
explain where the missing degrees went.


I didn't fail to explain them, Roy, you just failed to listen
to reason, ploinked me, and started uttering Big Lies about
me.

In my 75m mobile base-loaded bugcatcher antenna:
1. The coil occupies ~25 degrees of antenna.
2. The impedance discontinuity at the coil to stinger
junction provides a ~44 degree phase shift.
3. The stinger occupies ~11 degrees of antenna.

At resonance the antenna is electrically
25+54+11 = 90 deg long even though it is physically
only ~12 degrees long.

All of the "missing degrees" appear at the impedance
discontinuities but you already know that since I
explained this to you two years ago.
--
73, Cecil http://www.w5dxp.com



Gentleman.
An update on Gaussian antennas
Guffaws heard

Took apart my helix wound on a garbage can for 160M
which was 1.5 :1 form wound and decided to make it
in horizontal element form.
Wires were 28 feet in length and I wound them tightly on
a 2 inch plastic pipe with pairs of wires,
two wires up and two wires down.
Made three of these assemblies and let the insulated wire "spring"
so I could place them on a 20 foot plastic pipe ,again 2 inches
diameter
and then connected them up with wire nuts.
When near to the ground the resonant impedance was in the
hundreds and changed little in the hunt for a sweet spot.
When placed 70 feet up impedances went to pot so I made
another two assemblies and connected them to the antenna assy.
without changing the overal length. Impedance was less than 2:1
across the 160 metre band. This resonance point I would call a
std resonance, where as, the ground measured a anti resonance.
As you can see the antenna revolves arounda full wave and
thus does not require a ground plain and conforms with
my Gaussian definition for a radiator.( The radiator can be any
size ,shape or elevation as long as the material is diamagnetic
and in a state of equilibrium)
( This, by the way, can be seem as what Einstein was looking for
twenty years but without success)
As you can see proximity to ground upset the equilibrium,but when
raised
to 70 feet the length aproached the 7/4 WL and probably woulD have
finished up around there if I could raise it in excess of a 1/2WL.
Wire used was #18 insulated house wire.
The antenna has multi resonances with the resistive resonances
increasing in value until it was a maximum at 160 M.
Snow has arrived so I will stay with this form until spring
while working on it to make it an ALL FREQUENCY GAUSSIAN
DIRECTIVE ANTENNA.
Covered the element with plastic sheeting because freezing
rain would cling to the windings and make it heavy.


Got any opinions or comments that could add to my understanding
of my present antenna? Don't mind contraversy as any discussion
tends to shed light in unexpected corners.
Best regards
Art