[Towertalk] Mosley TA-33 question......

[Pete Smith]

At 09:24 PM 6/19/02 -0600, n4kg@juno.com wrote:
>You may want to obtain the data sheet for a TA32
>and compare dimensions with the TA33.
>
>Parasitic elements have a strong effect on feed impedance
>of the DE.  Removing an element without compensating for
>that change is highly likely to change the feed impedance
>(R and X).

Tom makes an excellent point.  Moreover, if the feedpoint impedance is far 
from 50 ohms, and the feedline is not a half-wavelength or mutiple, the 
resulting impedance transformation may make it appear that resonance (as 
indicated by an SWR minimum in the shack) is somewhere other than it really 
is.  for example, my C-3E stack, which is centered at 14.2 MHz, indicates 
lowest SWR at 14.45 in the shack.


73, Pete N4ZR

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