Cecil Moore wrote:

dansawyeror wrote:

If it is true it proves that a driving a "bad" load can cause the coax
feedline to radiate a significant portion of the feed energy. At this
point I am not sure what word to use other then 'bad', but I due
intend to perform experiments to measure and verify what is happening
and the model.

dansawyeror wrote:

Below is a link to a site that claims to model coax radiation from a
dipole.

http://www.smeter.net/feeding/feedpowr.php


We are in a position now to say what is wrong with that program.
Essentially, it violates the conservation of energy principle.

Energy cannot exist as both reflected power and radiated power
at the same time.

If the SWR is 1400:1, the feedline cannot be radiating much
because the reflected power is 99.7% of the forward power
and both are based on differential currents which don't
radiate. That leaves only 0.3% of the power available for
radiating by the feedline.

If 99.9% of the power is radiated by the coax braid, then the
feedline SWR must be very close to 1.6:1 because the ratio of
reflected power to forward power can be no more than 0.1/100.

As with cake, you cannot have your reflected power and radiate
it too. Reflected power plus radiated power cannot add up to
more than the forward power. In fact, Pfor = Pref + Prad
If 50% of the power is radiated by the antenna plus feedline,
then 50% of the power is reflected and the SWR is 5.83:1.

Bear in mind that current flowing in a conductor will always generate a
field. Alternating current flowing in a (straight) conductor will
always generate a radiating electromagnetic field. That radiating field
will convey energy if it is not nulled by another equal and opposite
field. You need to demonstrate that all the fields resulting from all
the currents are nulled in this scenario.

Back into the woodwork.

ac6xg