Parallel tank circuit
A tank circuit represents an antenna closed circuit where in the
absence of friction shows the action of electric field changing to a
magnetic field as a sample of perpetual motion. However perpetual
motion does not exist so to account for all forces involved we have to
determine the amount of friction. We cannot use a series circuit as we
have no way of determining friction OR the point of the curve crossing
the the zero reactance level.
Thus we have to use a parallel circuit where we can use the cross over
point as being a period where it is seen as balanced and in
equilibrium.
The reason we cannot use a series circuit or anything pertaining to a
fractional wave in examining the performance of a radiator is because
the impedance curve does not represent a true sine wave. After a
period of time has occurred the source replaces any frictional losses
that have occurred. To do this the amplitude of the curve at the
beginning of a cycle moves higher than any othe point on the curve
where it replaces and exceeds the frictional losses that have
occurred. By doing this it uses time that is not in accordance to a
true sine wave and detracts from the accuracy of the following curve.
This useage of time during a period or cycle must be accounted for if
one is to determine all forces involved, which is why equilibrium or
balance must be followed when determining the characteristics of
radiation. There fore ,it should be seen that a full wave length or
multiples there of should be considered when dealing with radiators
since otherwise we are ignoring the overshoot effect required to
replace frictional losses.
Modern computer programs equiped with an optimiser are equiped to deal
with this as they will modify any inputs such that they are in
accordance with Maxwells laws where all forces are considered.
In the case of a yagi it must be seen that each element radiates
including the last one where the value is unknown and not included in
a fudged result. If one supplies an input that does not pre guide a
planar solution all optimiser programs will account for all forces
involved and will always supply an array that is not planar as a yagi
shows.
Thus for accurracy with respect to Maxwells laws one must have an
array that is in equilibrium which reflects Newtons laws where vectors
outside the "boundary" such as gravity and the Earths rotatation is
reflected by opposing vectors within the boundary. The consequences of
this is that the rotation vector in combination of that of gravity
will always produce an array that opposes gravity alone as with a
vertical at 90 degrees to the Earths surface if one pursuit is
accuracy.
The requirement of equilibrium is shown by the law of Gauss which when
added by a time varying field equates to the laws of Maxwell which
demands the presence of equilibrium and shows that a static particle
must be present to provide mass to which, via accelleration or
decelleration, which serves as the carrier of charge or charge.
This in no way conflicts with ideas or theories that particles and
waves can provide similar properties under certain cercumstances but
instead provides proof that particles are the carriers of what is
known as communication.
Cheers and beers.
Art Unwin KB9MZ...xg
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