[TenTec] Antenna measurements

[Ken Brown]

> That's correct - it's charge acceleration and deceleration which 
> causes radiation. If you take a long wire and terminate it in its 
> characteristic impedance it will radiate - there doesn't need to be a 
> discontinuity at the end. Same for a terminated Rhombic.
>
>
>>  Whenever an AC current flows on a wire, there is an accompanying and 
>> inseparable AC electromagnetic field surrounding the wire. And the 
>> said AC field propagates in all directions. It is as simple as that. 
>> No special conditions are needed, and one doesn't have to do anything 
>> special in order to provoke radiation. 
Yep! And a transmission line is made to have very low radiation by 
making the currents in the two wires equal and opposite. The fields they 
generate then cancel each other out. The SWR does not matter as long as 
the currents are equal in magnitude and opposite in phase.

And yes an antenna radiates nicely regardless of whether it is resonant. 
As long as charge flows a field is produced. If the charges are 
accelerating it is an electromagnetic field and not just a magnetic field.

Perhaps it would help if QST didn't use so much space showing SWR curves 
for almost every antenna article they print. They may have not said it, 
but they have given the impression to many hams that the number one 
indicator of antenna performance is SWR. This is of course not the case, 
as a real good dummy load has a great SWR on all bands and is a lousy 
radiator of RF, but a good radiator of heat.

DE N6KB