>
>Pete Smith wrote:
>>
>> At the risk of fanning the flames again, I think the original question was
>> whether a change in line length could cause the apparent resonant frequency
>> of an antenna to change. My 20M antenna has a feedpoint impedance of 35-j14
>> at 14 mhz. If I mathematically attach a half-wavelength of RG-8 (using
>> TLA.EXE), the impedance at the input end of the cable becomes 36-j 13.3,
>> and the result, as you'd expect, is slightly lower SWR due to line loss.
>> however, if the line is pruned to 1/4 wave, the resulting input-end
>> impedance is 61.75+j23, and it appears that the antenna has magically moved
>> from being short at 14 MHz to being long. The SWR hasn't changed,
>> fundamentally, but the mix of reactance and resistance confronted by the
>> AMP sure has, unless I misunderstand what the program is telling me.
>>
>> 73, Pete Smith N4ZR
? looks close enough to me, Pete.
>>
>-----------------------
>
>Hi Pete,
>One thing most people on this reflector have forgotten or never really
>understood:
>
>SWR has NOTHING to do with resonance.
>
? Resonance is another way of saying that the reactance is zero. If the
SWR is zero, you have no reactance.
later, Bob, W5AH
- Rich..., 805.386.3734, www.vcnet.com/measures.
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