[Elecraft] how did I calculate the loss?

[Don Wilhelm]

----- Original Message -----

> Don,
> Does my 4-1 balun at the input of my K2 introduce losses and if so will
more power
> get to the antenna without the balun?
>

If the balun is doing it's proper job, it is not likely that additional
losses are introduced by its presence - it will convert the unbalanced
output of your tuner to a balanced condition.
I did not mean to imply that baluns are lossy - actually they are a good
antenna system to employ.
The point I was trying to inject is that the antenna system itself (and not
the balun) will determine whether the feedline currents are equal and
opposite - yes baluns do properly force their output currents to be equal
and opposite, but the antenna configuration is the real determining factor
in the overall balance question.

Part of the problem is that we usually think of balanced and unbalanced in
only two situations - perfectly balanced, and totally unbalanced.  In
reality, antenna systems can (and do) present situations that are somewhere
in the middle.  Unless the antenna itself is inherently balanced, or
inherently totally unbalanced, a balun may not be the best answer.

As an extreme example, consider an off center fed antenna (where the
feedpoint is neither a current maximum nor a current minimum).  If you
follow the antenna and feedline currents (remembering that 'mother nature'
demands that the current at the antenna ends be zero), there is no way that
the feedline currents can be made equal and opposite.  In that case, the
feedline will radiate over its length - if a balun is introduced along the
feedline to force the currents to be equal and opposite, the length of
feedline that will radiate is that between the balun and the antenna
feedpoint.  OTOH, if the balun is moved to the antenna feedpoint, the
currents introduced (launched) onto the antenna wires will be equal and
opposite and the antenna current pattern will be distorted because the
currents at the antenna ends must be zero - and the sum of all that
translates into loss somewhere in the system (that loss may or may not be at
a balun that might be present).

I have had many questions about this in the past, and challenges on a few
'fine points', but no one has been able to substantiate that it is
incorrect.  It has always worked out for me when considering antenna system
balance - and I have not yet found an effective way to 'force' the currents
to be balanced unless the antenna configuration itself permits that balance.

If anyone has further questions, I recommend we take it off the reflector.
While this is an interesting topic, it is off topic for the Elecraft
reflector.  There are plenty of other forums willing to discuss this subject
at length.

73,
Don W3FPR